Although humans make up only a tiny fraction of all life on the planet, our impact upon diversity and wildlife has been enormous. By some accounts, human activity is responsible for the loss of 80% of all wild animals and about 50% of all plants. Much of this loss was necessary to make way for farmed livestock for human consumption.
Just consider this fact: 70% of all birds on Earth are chickens and other poultry, whereas wild birds comprise a meager 30%. Were an alien archaeologist to visit our planet after humans went extinct, they would surely be staggered by the abundance of chicken fossils.
But before we became hooked on chicken eggs and hot wings, we most likely first started with geese.
Japanese archaeologists performing excavations at Tianluoshan, a Stone Age site dated between 7,000 and 5,500 years ago in China, found extensive evidence of goose domestication. They claim this is the earliest evidence of bird domestication reported thus far.
The team identified 232 goose bones, which paint a convincing picture that Tianluoshan may be the cradle of modern poultry.
First and foremost, the researchers performed radiocarbon dating on the bones themselves, rather than the sediments which covered the remains. This lends confidence that the goose bones are really as old as 7,000 years.
At least four bones belonged to juveniles no older than 16 weeks. This shows that they must have hatched at the site because it would have been impossible for them to fly in from somewhere else at their age. This is likely the case for the adult geese found there as well, given that wild geese don’t breed in the area today and probably didn’t 7,000 years ago either.
But, to be sure, the team led by Masaki Eda at Hokkaido University Museum in Sapporo, Japan, thoroughly broke down the chemical makeup of the ancient bones, showing the water they drank was local. The strikingly uniform size of the bred geese is also very indicative of captive breeding.
Although not by any means definitive, all of these lines of evidence converge to the same conclusion: geese were probably the first birds humans have domesticated, and this happened more than 7,000 years ago in China.
New Scientist reports that other studies have claimed that chickens were the first domesticated birds, as early as 10,000 years ago, also in avian-loving northern China. But the evidence, in this case, has proven contentious. Genetic analysis suggests chickens were domesticated from wild birds called red junglefowl, but these birds do not live that far north. Furthermore, the chicken bones weren’t directly dated. The firmest evidence of chicken domestication only appeared 5,000 years ago.
While most domestication research has focused on dogs and cattle, it’s refreshing to see new perspectives on the evolutionary history of poultry, upon which our food security depends so much.
The only good chocolate for dogs is a chocolate fur, like is majestic lab is rocking. Credit: Pixabay.
Unlike cats, which lack the ability to taste sweetness, dogs find chocolate just as appealing as humans. But while the dark treat can be a euphoric delight for us, it can be poisonous to canines.
That’s not to say that all dogs get poisoned by chocolate or that a candy bar is enough to necessarily kill your pet canine. The dose makes the poison. The weight of the dog also matters, so large canines should be able to handle a small amount of chocolate whereas smaller breeds might run into serious trouble.
Although you shouldn’t panic if your dog accidentally ingests chocolate, candy and other chocolate sweets should never be offered to dogs. Generally, you should treat chocolate as toxic to dogs and should make an effort to keep it away from them.
Why chocolate can be dangerous to dogs
Among the many chemical compounds found in dark chocolate and cocoa is theobromine. Formerly known as xantheose, theobromine is a bitter alkaloid compound that acts as a mild stimulant for the human body.
The consumption of theobromine is generally associated with positive effects, such as reduced blood pressure, improved focus and concentration, and enhanced mood. That’s in humans. In dogs, theobromine, as well as caffeine, raise the heart rate and can overstimulate the nervous system.
Because dogs can’t break down, or metabolize, theobromine as well as humans can, the compound is toxic to dogs, over a certain threshold, depending on their body weight.
Mild symptoms of chocolate toxicity occur when a canine consumes 20 mg of theobromine per kilogram per body weight. Cardiac symptoms occur at around 40 to 50 mg/kg and dangerous seizures occur at doses greater than 60 mg/kg.
This explains why a candy bar may cause a chihuahua (average weight 2 kg) to run in circles while Great Dane (average weight 70 kg) might feel just fine.
Darker, purer varieties of chocolate tend to be the most dangerous because they contain the highest concentration of theobromine. According to the USDA nutrient database, various chocolate/cocoa products contain the following amounts of theobromine per 100 grams;
Unsweetened cocoa powder: 2634 mg;
Baking chocolate (unsweetened): 1297 mg;
Dark chocolate (70% cocoa): 802 mg;
Mars Twix (twin bar): 39.9 mg;
White chocolate: 0 mg;
As a rule of thumb, chocolate poisoning in dogs generally occurs after the ingestion of 3.5g of dark chocolate for every 1kg they weigh, or 14g of milk chocolate for every kilogram.
Signs that your dog may be suffering from chocolate poisoning
Chocolate poisoning mainly affects the heart, central nervous system, and kidneys. The symptoms of theobromine toxicity usually appear within 6 to 12 hours after your dog eats too much chocolate and may last up to 72 hours. These include:
vomiting,
diarrhea,
restlessness,
increased urination,
tremors,
elevated or abnormal heart rate,
seizures,
and in extreme cases collapse and death.
Can chocolate kill dogs?
In short, yes. However, fatalities in dogs due to chocolate poisoning are very rare. According to the Veterinary Poisons Information Service from the U.S., out of 1,000 dog chocolate toxicity cases recorded in its database, only five dogs died.
What do if your dog eats chocolate
If you caught your dog eating chocolate or you suspect this may have happened, it is best to call your veterinarian and ask for advice on how to proceed going forward. Based on your dog’s size and the amount and kind of chocolate ingested, the veterinarian may recommend monitoring your dog for any symptoms of poisoning or ask that you immediately come to the clinic.
If there are good reasons to believe potentially dangerous chocolate poisoning may be imminent, and as long as your pet consumed the chocolate less than two hours ago, the veterinarian may induce vomiting.
Sometimes, the dog may be given doses of activated charcoal, which helps to flush toxins out of the body before they are absorbed into the bloodstream.
In very extreme cases of poisoning, the veterinarian might administer medications and/or intravenous fluids to provide additional treatment.
Keep chocolate away from dogs
There’s no reason to believe chocolate isn’t as tasty to dogs as it is to humans. Unfortunately, many dog owners are ignorant to the fact that chocolate can poison their pets and intentionally offer chocolate snacks as a treat.
Usually, this isn’t a problem for very large breeds when they ingest small amounts of chocolate, but smaller dogs can suffer greatly and even die in extreme cases due to theobromine poisoning.
If you are aware that chocolate can poison your pet, you have no excuse to keep sweets accessible. It is advisable to keep any chocolate items on a high shelf, preferably in a closed-door pantry. Guests and children should be kindly reminded that chocolate is bad for dogs and that they shouldn’t offer chocolate treats regardless of how much the pet begs for them.
Most chocolate poisoning in dogs occurs around major holidays such as Christmas, Easter, or Valentine’s Day, so these are times when you should be extra careful.
Thiomargarita magnifica next to a dime for scale. Credit: video screen capture.
Until Antoni van Leeuwenhoek first discovered bacteria in 1676, we didn’t even have a name for these tiny microbes. Viruses, which are an order of magnitude smaller than bacteria and require even more powerful microscopes to observe, weren’t discovered until 1892 when Dmitry Ivanovsky isolated the tobacco mosaic virus. Imagine everyone’s surprise when scientists recently discovered a bacterium so large it’s visible to the naked eye.
This giant string-like bacterium, native to the Caribbean mangroves, can grow up to 2 centimeters in length, about the size of a fly. It’s about 5,000 times larger than most other microbes, stretching the limits of what we thought biological possible for a single-celled organism.
Christened Thiomargarita magnifica by an international team of researchers, which included scientists from the Lawrence Berkeley National Laboratory in the US, CNRS in France, the newly discovered organism dwarfs other so-called “giant bacteria” by about 50-fold.
“All too often, bacteria are thought of as small, simple, ‘unevolved’ life forms—so-called ‘bags of proteins,’” Chris Greening, a microbiologist at Monash University, Clayton, who was not involved in the study, told Science. “But this bacterium shows this couldn’t be much further from the truth.”
The secret to T. magnifica‘s chunky size may lie in the arrangement of its genetic material, which is totally atypical. Bacteria and other single-cell microbes called archaea are classed as prokaryotes, while multicellular organisms like trees and humans are classed as eukaryotes. One of the defining differences between the two is that prokaryotes have free-floating DNA, while eukaryotes package their genetic code in a nucleus.
However, T. magnifica is blurring the lines between eukaryotes and prokaryotes because its huge genome is not free-floating inside its cell as in other bacteria. Instead, it’s encased in a membrane. When researchers sequenced the genome, they were amazed by its size: 11 million bases that line up to form 11,000 genes. For comparison, your run-of-the-mill bacterium only has about 4 million bases and about 3,900 genes.
“Importantly, we show that centimeter-long Thiomargarita filaments represent individual cells with genetic material and ribosomes compartmentalized into a novel type of membrane-bound organelle. Sequencing and analysis of genomes from five single cells revealed insights into distinct cell division and cell elongation mechanisms,” the researchers wrote in a paper that appeared in the preprint server bioRxiv. The findings haven’t been peer-reviewed yet.
These extraordinary findings suggest that the two major branches of life aren’t all that different after all — and T. magnifica could be a missing link that explains how complex life evolved from the most primitive single-celled organisms more than a billion years ago.
The giant bacterium’s DNA is encased in a sac embedded in its membrane. It has another much larger membrane sac that is filled with water and takes up 73% of the microbe’s volume. This external sac allows the organism to grow so large, while keeping its essential organelles packed in a small space to facilitate the diffusion of molecules in and out of the microbe.
“These unique cellular features likely allow the organism to grow to an unusually large size and circumvent some of the biophysical and bioenergetic limitations on growth,” said the researchers, which have compared T. magnifica to other microbes called Large Sulfur Bacteria, which form very long filaments that may reach several centimeters in length. However, unlike T. magnifica, these sulfur bacteria are composed of thousands of individual cells, each no larger than 200 micrometers.
The origin of complex life is one of the most important, yet unanswered, questions in biology. Most bacteria are tiny and dull, but some are complex and feature innovative biological machinery. T. magnifica is a prime example of the latter, with its large genome, gigantic cell size, and its unheard-of compartmentalization of genetic material in its membrane.
“T. magnifica adds to the list of bacteria that have evolved a higher level of complexity. It is the first and only bacteria known to date to unambiguously segregate their genetic material in membrane-bound organelles in the manner of eukaryotes and therefore challenges our concept of a bacterial cell,” the researchers wrote.
Many birds that live together cooperate with each other to ensure and enhance the survival and safety of the group. Magpies are no exception, as some scientists who were testing new types of tracking devices for birds would learn. The crafty birds helped each other to remove the devices, much to the surprise of the researchers. But what they lost in GPS trackers and hours of fieldwork, the researchers gained ten-fold in their understanding of these remarkable social species.
Image credit: Wikipedia Commons.
The magpie is a relatively large bird (about 300 grams) native to Australia, omnipresent across the continent. It lives in small social groups, occupying and strongly defending a single territory. Although it’s an abundant species, not much is known about its movement, social interaction within and between family groups, and spatial and temporal range.
A group of researchers from the University of the Sunshine Coast wanted to further learn about the movement and social dynamics of these very intelligent birds while testing a new tracking device. But things didn’t go as planned. “The birds outsmarted us,” Dominique Potvin, an animal ecologist and study co-author, wrote in a blog post.
“The magpies began showing evidence of cooperative ‘rescue’ behaviour to help each other remove the tracker,” Potvin wrote. “While we’re familiar with magpies being intelligent and social creatures, this was the first instance we knew of that showed this type of seemingly altruistic behaviour: helping another member of the group.”
A very clever group of birds
Most trackers are usually too big to be used on small and medium-sized birds. There are some smaller trackers but they are limited in the amount of data they can store or their battery life. That’s why Potvin and the group of researchers were excited with their new, state-of-the-art tracker, which weighs less than one gram and is capable of re-charge wirelessly.
For their study, the researchers trained a group of magpies (Gymnorhina tibicen) to visit an outdoor feeding station. Five of these birds were fitted with the device. A harness held the tracker tight and to remove it, you would need a “good pair of scissors or a magnet,” according to Potvin. But things didn’t go as planned. Apparently, a friend’s crafty beak will do.
Only 10 minutes after fitting the fifth and last tracker, an adult female without a tracker started to help a younger bird to remove the harness – eventually succeeding. This pattern was repeated in the following hours, with almost all trackers of the experiment removed. By the third day, the dominant male had its tracker dismantled.
“We don’t know if it was the same individual helping each other or if they shared duties, but we had never read about any other bird cooperating in this way to remove tracking devices,” Potvin wrote in the blog post. “The birds needed to problem solve, possibly testing at pulling and snipping at different sections of the harness with their bill.”
The researchers said they didn’t expect the magpies to see the tracker as some sort of parasite that had to be removed. But that’s what happened. There’s only one similar example of this type of behavior ever recorded. The Seychelles warblers (Acrocephalus sechellensis) were seen helping release others in the group from sticky seed clusters.
While the experiment failed, the researchers highlighted the importance of tracking magpies. They are very vulnerable to heatwaves, which are becoming more common and intense amid the climate crisis. A recent study found that the survival rate of magpie chicks amid heatwaves is as low as 10%, with higher temperatures also affecting their cognitive performance.
From the east of India, all through to the north of Australia, one fearsome, cold-blooded predator stalks the coasts. This hypercarnivore will contend with any that enters its watery domain, from birds to men to sharks, and almost always win that fight. Fossil evidence shows that this species has been plying its bloody trade for almost 5 million years, remaining virtually unchanged, a testament to just how efficient a killing machine it is. Looking it in the eye is the closest thing we have to staring down a carnivorous dinosaur.
Saltwater crocodile at the Australia Zoo, Beerwah, South Queensland. Image credits Bernard Dupont / Flickr.
This animal is the saltwater crocodile (Crocodylus porosus). It has the distinction of being the single largest reptile alive on the planet today, and one of the oldest species to still walk the Earth.
Predatory legacy
The earliest fossil evidence we have of this species dates back to the Pliocene Epoch, which spanned from 5.3 million to 2.6 million years ago.
But the crocodile family is much older. They draw their roots in the Mesozoic Era, some 250 million years ago, when they branched off of archosaurs (the common ancestor they share with modern birds). During those early days, they lived alongside dinosaurs.
Crocodiles began truly coming into their own some 55 million years ago, evolving into their own species in the shape we know them today. They have remained almost unchanged since, a testament to how well-adapted they are to their environments, and the sheer efficiency with which they hunt.
This makes the crocodile family, and the saltwater crocodile as one of its members, one of the oldest lineages alive on the planet today.
The saltwater crocodile
With adult males reaching up to 6 or 7 meters (around 20 to 23 ft) in length, this species is the largest reptile alive today. Females are smaller than males, generally not exceeding 3 meters in length (10 ft); 2.5 meters is considered large for these ladies.
Image credits fvanrenterghem / Flickr.
The saltwater crocodile will grow up to its maximum size and then start increasing in bulk. The weight of these animals generally increases cubically (by a power of 3) as they age; an individual at 6 m long will weigh over twice as much as one at 5 m. All in all, they tend to be noticeably broader and more heavy-set than other crocodiles.
That being said, they are quite small as juveniles. Freshly-hatched crocs measure about 28 cm (11 in) in length and weigh an average of only 71 g — less than an average bag of chips.
Saltwater crocodiles have large heads, with a surprisingly wide snout compared to other species of croc. Their snout is usually twice as long overall as they are wide at the base. A pair of ridges adorn the animal’s eyes, running down the middle of their snout to the nose. Between 64 and 68 teeth line their powerful jaws.
Like their relatives, saltwater crocodiles are covered in scales. These are oval in shape. They tend to be smaller than the scales of other crocodiles and the species has small or completely absent scutes (larger, bony plates that reinforce certain areas of the animal’s armored cover) on their necks, which can serve as a quick identifier for the species.
Young individuals are pale yellow, which changes with age. Adults are a darker yellow with tan and gray spots and a white or yellow belly. Adults also have stripes on the lower sides of their bodies and dark bands on their tails.
That being said, several color variations are known to exist in the wild; some adults can maintain a pale coloration throughout their lives, while others can develop quite dark coats, almost black.
Behavior, feeding, mating
Saltwater crocodiles are ambush predators. They lie in wait just below the waterline, with only their raised brows and nostrils poking above the water. These reptiles capture unsuspecting prey from the shore as they come to drink, but are not shy to more actively hunt prey in the water, either. Their infamous ‘death roll’ — where they bite and then twist their unfortunate victim — is devastating, as is their habit of pulling animals into the water where they drown. But even their bite alone is terrifying. According to an analysis by Florida State University paleobiologist Gregory M. Erickson, saltwater crocodiles have the strongest bite of all their relatives, clocking in at 3,700 pounds per square inch (psi).
That’s a mighty bitey. Image credits Sankara Subramanian / Flickr.
Apart from being the largest, the saltwater crocodile is also considered one of the most intelligent reptiles, showing sophisticated behavior. They have a relatively wide repertoire of sounds with which they communicate. They produce bark-like sounds in four known types of calls. The first, which is only performed by newborns, is a short, high-toned hatching call. Another is their distress call, typically only seen in juveniles, which is a series of short, high-pitched barks. The species also has a threat call — a hissing or coughing sound made toward an intruder — and a courtship call, which is a long and low growl.
Saltwater crocodiles will spend most of their time thermoregulating to maintain an ideal body temperature. This involves basking in the sun or taking dips into the water to cool down. Breaks are taken only to hunt or protect their territory. And they are quite territorial. These crocodiles live in coastal waters, freshwater rivers, billabongs (an isolated pond left behind after a river changes course), and swamps. While they are generally shy and avoidant of people, especially on land, encroaching on their territory is one of the few things what will make a saltwater crocodile attack humans. They’re not shy to fight anything that tresspasses, however, including sharks, monkeys, and buffalo.
This territoriality is also evident in between crocs. Juveniles are raised in freshwater rivers but are quickly forced out by dominant males. Males who fail to establish a territory of their own are either killed or forced out to sea. They just aren’t social souls at all.
Females lay clutches of about 50 eggs (though there are records of a single female laying up to 90 in extraordinary cases). They will incubate them in nests of mud and plant fibers for around 3 months. Interestingly, ambient temperatures dictate the sex of the hatchlings. If temperatures are cool, around 30 degrees Celsius, all of them will be female. Higher sustained temperatures, around 34 degrees Celsius, will produce an all-male litter.
Only around 1% of all hatchlings survive into adulthood.
Conservation status
Saltwater crocodiles have precious few natural predators. Still, their skins have historically been highly prized, and they have suffered quite a lot from hunting, both legal and illegal. Their eggs and meat are also consumed as food.
In the past, this species has been threatened with extinction. Recent conservation efforts have allowed them to make an impressive comeback, but the species as a whole is much rarer than in the past. They are currently considered at low risk for extinction, but they are still of especial interest for poachers due to their valuable meat, eggs, and skins.
Saltwater crocodiles are an ancient and fearsome predator. They have evolved to dominate their ecosystems, and do so by quietly lurking just out of sight. But, like many apex predators before them, pressure from humans — both directly, in the form of hunting, and indirectly, through environmental destruction and climate change — has left the species reeling.
Conservation efforts for this species are to be applauded and supported. Even though these crocodiles have shown themselves willing to attack humans if we are not careful, we have to bear in mind that what they want is to be left alone and unbothered. It would be a pity for this species, which has been around for millions of years, which has come from ancient titans, survived for millennia and through global catastrophe, to perish.
The toughest animals on Earth are often not what you expect. A prime example is the eight-legged tardigrades capable of surviving extreme heat, cold, and even the vacuum of space. But there’s another tough guy you should know about, especially since they often like to take on humans. Meet the East African tick, a blood-sucking arachnid that can go without food for at least 8 years, and with a lifespan of over 27 years. What’s more, females have been able to lay eggs even 4 years after the last male in their group had died.
The remarkable longevity and resilience of the East African (Argas brumpti) tick were just recently revealed by a rare study almost 60 years in the making, which could be a separate story in itself, illustrating the virtues of patience in science.
It all started in 1976, when Julian Shepherd, an associate professor of biological sciences at Binghamton University in New York, was given six adult females, four adult males, and three nymphs of A. brumpti collected from caves near Nairobi, Kenya. He decided to monitor them in his lab in a habitat with stable conditions, where they were fed periodically on mice, rabbits, or drawn rat blood.
For years, the captive ticks enjoyed their regular feast until one day Shepard simply stopped giving them blood when his lab ran out of rabbits and mice to feed on. Little did the biologist realize at the time that, even starving, his original group of ticks would survive until the next century.
East African ticks have soft and leathery skins, unlike the hard shell sported by the common types of ticks that you’ll find in the parks and countryside. And unlike your run-of-the-mill tick, Argas brumpti is not reported to carry any diseases, although its bites can cause substantial, painful lesions with aftereffects sometimes persisting for many months and even years, something that Shepard knows from first-hand experience.
In their natural habitat, the ticks reside in shallow caves, rocky areas, or dust-bath areas used by their favorite prey, such as small to large mammals and lizards, notably in the dust around termite mounds that large mammals rub against. This perennially dry environment with few opportunities to encounter hosts may explain A. brumpti‘s extreme longevity, even within a taxon renowned for sustained survival even without food or water.
“I am always enthralled by the adaptations of organisms to their environment—in this case, a dry environment with virtually no access to water for long periods of time and a lifestyle that must wait for very long intervals of no food between encounters with host animals,” Shepherd said in a statement.
Adaptations to its environment may explain another incredible feat. Four years after the last original tick died, the females continue to live for another four years. These hungry females were eventually fed, and much to Shepherd’s surprise, at least one of the females laid a batch of eggs. This second generation of offspring is still alive and apparently healthy to this day, being 26 years old and counting. The oldest tick from the original batch died after 27 years, during which they were deprived of food for eight years.
One explanation is that the female ticks are capable of parthenogenesis, also known as “virgin births” because embryos can grow and develop without fertilization by sperm. But Shepherd thinks this is extremely unlikely. Instead, the females are probably capable of long-term sperm storage until they have ample food, at which point the sperm moves up the reproductive tract and fertilizes eggs.
In any case, both this longevity and long-term storage are records for any species of tick — and these insights could prove useful beyond the remarkable nature of conducting a 60-year experiment. That’s something for other researchers to learn though, as the ticks have been shipped to South Africa for further study, while Shepherd is now moving onto new research on moths and the physiology of their sperm.
“Research on how organisms master such challenges can inform understanding of how other organisms, including us, might manage similar challenges,” Shepherd said.
Map showing Balkanatolia 40 million years ago and at the present day. Credit: Alexis Licht & Grégoire Métais.
For millions of years, Western Europe’s megafauna was literally worlds apart from that in Asia, owed to impenetrable natural barriers that allowed species on both continents to evolve and diverge. But that all changed in the blink of an eye, geologically speaking, after the more robust and adaptable Asian mammals poured into Europe, where they quickly replaced the endemic fauna. How exactly this event, known as the Grande Coupure, panned out has always been a mystery, but a new study is filling the gaps in our knowledge by proposing an interesting hypothesis: the Asian mammals invaded through an ancient landmass called Balkanatolia.
If the name Balkanatolia rings a bell, it’s because it refers to the present-day regions of the Balkans and Anatolia, which 50 million years ago formed an isolated archipelago, separate from the neighboring continents of Europe, Africa, and Asia. The name Balkanatolia was recently given by researchers at the French National Center for Scientific Research in a new study that highlights the biogeographic province’s major role in the Grande Coupure, which occurred some 34 million years ago.
That’s because examinations of previous fossils found in both the Balkan peninsula and Anatalonia — some of which date as far back as the 19th-century– performed by the researchers led by paleogeologist Alexis Licht showed that Asian mammals started colonizing southern Europe as early as 5 to 10 million years prior to the Grande Coupure.
In a subsequent review of this fossil record, the researchers uncovered patterns that allowed them to reconstruct the biogeographic history of the region over the span of millions of years.
The researchers found that for much of the Eocene Epoch (55 to 34 million years ago), the Balkans and Anatolia harbored homogeneous terrestrial fauna, which was distinct from that in continental Europe and Asia. Some of these mammals included marsupials of South American origin and large herbivorous mammals resembling hippos, known as Embrithopoda. The presence of these distinct animals just makes sense for an isolated archipelago, which is why the researchers proposed the existence of Balkanatolia.
However, Balkanatolia would soon be greeted by some uninvited guests. New fossil deposits from Büyükteflek in Turkey, dated to 38 to 35 million years ago, clearly belonged to mammals with an Asian lineage — the earliest of their kind discovered in Anatolia until now. These include fossils belonging to Brontotheres, huge animals resembling large rhinoceroses that died out at the end of the Eocene.
From this amalgam of fossils from different eras, the researchers pieced together a story: Balkanatolia comprised a single landmass isolated from the rest of the continents beginning with 50 million years ago, but would be colonized some 40 million years ago by Asian mammals. How exactly these animals reached the archipelago is not understood, but it seems like the region became a stepping stone for the Asian mammal invasion. The straight Eurasian route through modern-day Russia was not a viable route due to the huge glaciers and other geographical obstacles.
It is likely that a major glaciation event, which lowered sea levels some 34 million years ago, formed a bridge between Balkanatolia to Western Europe, releasing the floodgates of invasive Asian species. In no time, Western Europe endemic animals like Palaeotheres, an extinct group distantly related to present-day horses, but more like today’s tapirs, became extinct and were replaced by more diverse and resilient fauna including mammal families found today on both continents.
In other words, these findings suggest that the Grande Coupure was actually a two-stage event. In the first event, Asian mammals colonized Balkanatolia, where they replaced much of the existing fauna. Then, taking advantage of shifting geographical conditions due to climate change, the invasive species continued their conquest in the rest of the European continent.
“This colonization event was facilitated by a drop in global eustatic sea level and a tectonically-driven sea retreat in eastern Anatolia and the Lesser Caucasus during the late middle Eocene. These paleogeographic changes instigated the demise of Balkanatolia as a distinct biogeographic province and paved the way for the dispersal of Asian endemic clades before and during the Grande Coupure in western Europe,” the authors wrote in their study published in Earth-Science Reviews.
One of the more obscure animals out there, fisher cats (Pekania pennanti) or ‘fishers’, in short, are predators endemic to North America. Despite the name, these animals are not cats, and they do not fish. They are, however, increasingly moving into a lot of urban and suburban areas across the USA.
Image credits of USFWS Pacific Southwest Region / Flickr.
Fisher cats are slim, short-legged mammals that resemble weasels or small wolverines. They can grow to about 145 centimeters in length (4 ft 9 in) including the tail. They’re covered in dark-brown fur, which is glossy and thick in the winter, and more mottled in the summer. They have rounded ears, and overall look quite cute and cuddly. Don’t let that fool you, however: fisher cats have vicious, retractable claws, and are quite fearsome predators for their size.
The species is endemic to various areas of North America. New England, Tennessee, the Great Lakes area, and the northern stretches of the Rocky Mountains all house populations of fisher cats. Smaller populations have also been reported in California, the southern Sierra Nevada, and the west coast of Oregon. The boreal forests of Canada also make great homes for these mammals.
The cat that’s not a cat
Taxonomically speaking, fisher cats are closely related to martens, being part of the Mustelidae family. This is the largest family in the order of Caniformia (‘dog-like’ animals) and the greater order Carnivora (meat-eaters). As such, they’re part of the most successful and rich group of predators on the planet.
Despite this taxonomic allegiance to the group Carnivora, fisher cats are omnivorous. They will happily hunt a wide range of animals of comparable size to them. They are of the very few animals that even attempt to hunt porcupines, and do so quite successfully, but prefer to hunt hares. They’re not above scouring the forest floor for plants to eat, however. They generally forage around fallen trees, looking for fruits, mushrooms, nuts, and insects. A bit surprisingly, given their name, fisher cats only very rarely eat fish.
It’s not exactly clear, then, how the animal got its name. Folklore says that fisher cats would steal the fish the early settlers used to bait traps in the Great Lakes region, but this is wholly unconfirmed. More likely, the ‘fisher’ in ‘fisher cat’ comes from ‘fisse’, the Dutch equivalent of the word ‘fitch’, from early settlers in the region. It’s also possible that it draws its roots in the French term ‘fishe’. These words refer to the European polecat or its pelt, respectively; given that fur trade was an important source of income for early settlers, it is likely that fisher cats were prized and sought-after for their pelts, and the species became associated with the polecat, who was raised for fur in Europe.
It’s easy to see why their pelts were so prized. Image via Wikimedia.
However, due to this association, fisher cats have been hunted to extinction in some parts of their natural habitat. Due to a drop in hunted pelts since the Americas were first colonized by Europeans, the animals are making a comeback and their populations are recovering and moving back into the areas they previously inhabited. Despite this, legal harvesting for fur, through trapping, is still one of the main sources of information regarding their numbers at our disposal right now.
A baby fisher cat is called a ‘kit’. Females tend to give birth to litters of one up to four kits at a time in the spring and nurture them until late summer. The kits are sightless and quite helpless at first, but become well able to take care of themselves by summertime and leave in search of their own mates.
How do they live?
Fishers spend most of their time on the ground, and have a marked preference for forested lands compared to other habitats. They’re most often found in boreal or conifer forests, but individuals have been seen in transition forests as well, such as mixed hardwood-conifer forests. They seem to avoid areas where overhead cover isn’t very thick, preferring at least 50% coverage.
Female fisher cats also make their dens in moderately large and large trees when giving birth and rearing their kits. Because of these factors, they’re most likely to be seen in old-growth forests, since heavily-logged or young forests seem not to provide the habitat that fishers like to live in.
Towards the west of the continent, where fires routinely clear forests of fallen trees (the most-liked foraging environments of the fishers), these animals tend to gravitate towards forests adjacent to bodies of water (riparian forests). They also seem to not be fond of heavily snowed areas regardless of geographical location.
Despite their habitat preferences, fisher cats have been seen encroaching ever more deeply into urban landscapes, most likely drawn by the prospect of easy food. While it is still unclear whether fisher cats hunt for pets such as household cats or small dogs, such activities would be within their abilities. Most likely, however, they search for food items discarded in trash cans.
Fisher cats stay away from humans for the most part and avoid contact. They will defend themselves if they feel cornered, however. They are quite small, so the chances of a deadly encounter with a fisher cat are slim to none, but if you ever meet one, don’t be fooled by their cuddly exterior. Give it space; their claws and fangs can be quite nasty, and there’s always the risk of infection when dealing with wounds from wildlife.
Today, these furry mammals are listed as Least Concern on IUCN Red List of Threatened Species; they are making quite a successful comeback following their historic lows. Still, habitat destruction and human encroachment remain serious issues for the species. Their ever-more-frequent sightings in cities and urban landscapes across North America are a warning sign of an issue wildlife everywhere faces: humans are taking up more space than ever, so they are coming to visit our cities, as well. Depending on what we do in the future, they may be forced to set up shop here for good.
Lettuce might not seem like much for the massive sea cows that can weigh up to 1,000 pounds. But in Florida, that’s exactly what they need. In several parts of the state, seagrass, their main food source, is disappearing. So as a last ditch effort, state officials have started feeding manatees with lettuce. And it seems to be working.
Image credit: Flickr / US Geological Survey.
About 350 manatees are coming to eat the vegetables every day at a temporary field response station in Cape Canaveral as part of a program launched earlier this year by the Florida Fish and Wildlife Conservation Commission. The state officials distribute roughly 20,000 pounds of vegetation a week, mainly romaine and butter leaf lettuce.
“We’re making a difference. It gives us the greatest exposure to the greatest number of animals,” Ron Mezich of the Florida Commission said during an online news conference this week. “At this point in time, we have been successful. Manatees are eating the romaine. We are exposing a large number of animals to this food source.
Normally, wildlife experts ask people not to feed wild animals as they start to associate humans with food. In fact, it’s still a crime in Florida for a person to feed manatees on their own. However, this is an official program. While the pilot program takes place, officials are asking people not to feed manatees on their own and instead donate money and report any sick manatees.
The government is also working with several facilities to rehabilitate distressed manatees that are found alive. These include zoos, marine aquariums, and the SeaWorld theme park in Florida. Over 150 manatees were rescued last year, some requiring lengthy care and others that were returned to the wild in a short time.
The big challenges for manatees
Over 1,000 manatees died in Florida last year, according to the state’s Fish and Wildlife Conservation Commission. This is much more than the 637 deaths recorded last year and well above the previous record of 830 in 2013. The problem doesn’t seem to be going away, with authorities expecting another bad year with more deaths to come.
This program is a temporary solution, but the problems manatees face in Florida are long-term.
“The cold hard fact is: Florida is at a water quality and climate crossroads, and manatees are our canary in the coal mine,” said J.P. Brooker, Florida director for the Ocean Conservancy environmental group, in an opinion piece. They are dying off in record numbers because we humans have made Florida waters inhospitable to them.”
The slow-moving manatees have long struggled to coexist with humans. While some of the deaths and injuries are due to boat strikes that is not the main problem. Polluted water runoff from agriculture and sewage is causing algae blooms in estuaries, which affect the seagrass that the manatees rely on. Climate change is making it worse.
To make it even more tricky, manatees are slow to reproduce. One calf is born every two to five years after manatees reach sexual maturity at the age of five. The animals were listed as endangered in 1996 and their status later changed to threatened in 2017. There’s now a push to restore the endangered label to get more attention.
There are about 7,500 manatees in Florida, according to the commission, in some cases concentrated in areas that are a big tourist attraction. One hot spot is the Indian River Lagoon, home to hundreds of animals. But parts of the lagoon are now choked with pollution and algae, which means seagrass can’t grow and manatees can’t eat.
The government of the Faroe Islands is reviewing the country’s annual dolphin-and-whale hunt.
Image credits Wikimedia.
According to representatives of the administrative body, no decision has yet been made and several options are being considered. A final decision on the future of this hunt is expected in the coming weeks, they added.
Reviewing tradition
The Faroes are a pretty tiny archipelago to the north of the United Kingdom. Politically, they are an autonomous territory, part of the Kingdom of Denmark, much like Greenland. And, for the longest time now, it has maintained the custom of the “grindadráp”, or “grind” for short.
During grindadrap, fishermen seek out groups of dolphins or pilot whales and surround them with a semi-circle of fishing boats. The animals are then driven into a shallow bay, where they are subsequently beached. Fishermen on shore then slaughter the animals, which are now easy pickings.
Last year’s grind, which took place on September 12, 2021, occured on a much larger scale than any previously. The event, which saw the slaughter of more than 1,400 Atlantic white-side dolphins (Lagenorhynchus acutus) sparked quite a wave of international outrage. Following that event, the country’s Prime Minister Bardur a Steig Nielsen ordered an official re-evaluation of the hunt.
That re-evaluation is now complete. The government discussed its conclusion at a meeting in Torshavn on Tuesday. Despite the public interest in this topic, no decision seems to have been reached just yet.
“It was a first meeting. No decisions were taken,” an official in the prime minister’s office told Agence France Presse, adding that “several options” are on the table, with a final decision expected “in a few weeks”.
A petition with almost 1.3 million signatures calling for a ban on the hunt was also submitted to the Faroe government on Monday, adding further pressure on lawmakers to come to a decision.
That being said, the hunt still enjoys wide support in the Faroes. It is part of local tradition, and this hunt has been a vital food source for local communities historically. It is very unlikely that all the customs surrounding the grind will be banned; the government explained that only the hunt is currently under review, not the whole tradition.
Bush fire, drought, habitat loss, and disease have taken a toll on the once abundant koalas in Australia over the years, to the point that the government has now listed the iconic marsupial as endangered for most of its territory. The decision comes two years after a parliamentary investigation predicted the koalas would be extinct in the New South Wales region by 2050 if no urgent government intervention was implemented.
Image credit: Flickr / Mathias Appel.
Koalas, the quintessential Australian animal, had been rated “vulnerable” in 1999, but its status has now been upgraded amid its declining numbers. The reclassification applies to Queensland, New South Wales and the Australian Capital Territory (ACT), where most koalas live. The Environment Ministry said a recovery plan for koalas would soon be set in place.
The plan includes the creation of laws to protect koalas and their natural habitat. Additionally, the government would commit about $35 million in the next four years for koala recovery and conservation efforts. This was welcomed by NGOs but they described it as a “drop in the ocean” if the causes of the species decline aren’t tackled.
“This listing adds priority when it comes to the conservation of the koala,” Environment minister Sussan Ley said in a press conference. “The impact of prolonged drought, followed by the black summer bushfires, and the cumulative impacts of disease, urbanization and habitat loss over the past twenty years have led to this.”
A very challenged species
The critical situation of the koala got global attention in 2019 when bush fires raged over millions of hectares, disrupting the animal’s habitat. A report by the World Wildfire Fund estimated that more than 60,000 koalas were “killed, injured or affected in some way.” It wasn’t just koalas, three billion other animals were affected by the fires.
In response, the Australian government committed almost $13 million, half of which to be used in restoring the habitats and half in health research. But that wasn’t enough, environmental NGOs agreed. In 2020, WWF, the Human Society, and the Fund for Animal Welfare collectively nominated the animal for listing as an endangered species.
The koala population dropped to less than 58,000 in 2021 from more than 80,000 in 2018, according to a report by the Australian Koala Foundation (AKF) published last year. The worst drop was in the state of New South Wales, where the numbers plummeted by 41%. There were no upward numbers in any region, with some with as few as five koalas.
“Posing with a cuddly Koala and announcing a big chunk of money is undeniably a vote winner. But, if the Federal Government is serious about saving the species, their splash of cash needs to be put a horse in front of the cart – and that is decent mapping to know where the Koalas are or could be,” Deborah Tabart, head of AFK, said in a statement.
Koalas currently face a wide array of threats in Australia. A whole colony can be wiped out by a single bushfire, according to AFK. The animals are also affected by diseases caused by the chlamydia bacteria, such as conjunctivitis and urinary tract infections. Clearing of land for infrastructure and agriculture development can also lead to loss of their habitat.
While everyone is, hopefully, aware that letting your dog defecate freely on the street is a big no-no, we tend to be much more lenient when this happens on the bare ground, particularly outside cities. Poop is a fertilizer, so your pooch’s number two is actually doing nature a favor. Well… not really.
According to researchers at Ghent University in Belgium, dogs defecating and urinating unhindered in natural parks close to cities and towns have a dramatic negative impact on biodiversity due to overfertilization. As a result of nitrogen pollution, the composition of plants in the ecosystem can change substantially, with more nutrient-demanding species outcompeting specialists.
For their study, the researchers studied four peri-urban nature reserves located less than five kilometers from Ghent, a medium-sized city in Belgium. These nature reserves refer to any forests, grasslands, wetlands, and heathlands in populated areas. The areas selected for the study were specifically managed for biodiversity conservation and contained vulnerable species-rich vegetation.
For a year and a half, the researchers identified and pinpointed hundreds of trails where dogs regularly poop and urinate. They collected soil and plant samples to determine the inputs of nitrogen and phosphorus inputs. The nutrients are essential to the growth of all living things, but when in excess can pollute natural areas.
Dog poop is made of three-quarters water plus undigested food, including carbohydrates, fiber, proteins, and fats from the canine’s digestive system, along with a range of digestive bacteria, some of which can be harmful. Since dogs are fed in households, their feces and urine count as net inputs in natural ecosystems, in contrast to grazing cattle and sheep that feed off the land and recycle nutrients within the ecosystem.
The researchers found that dogs contributed 11 kilograms of nitrogen and 5 kilograms of phosphorus per hectare. For comparison, in ecosystems free of dogs (or humans for that matter), each hectare of protected natural land sees about 0.5 kilograms of nitrogen deposited each year.
Since the vegetation is used to much lower nutrient inputs, this extra waste leads to overfertilization that actually hinders the growth of more sensitive plants. More resilient flora like nettles and hogweed flourish though, driving out other plants and reducing biodiversity in the process. This happens particularly around trails since the nutrients released by dogs are not deposited uniformly but in patches.
The solution is rather simple: bag your dog’s poop just as you would in urban parks. The researchers found that disposal bags and pooper-scooper stations can reduce extra phosphorus by 97% and nitrogen by 56%. Keeping dogs on a leash can also restrict the deposited nutrients to significantly smaller areas, concentrated in the near vicinity of trails. In particularly sensitive areas with plants adapted to nutrient-poor soils, park rangers could ban dogs altogether.
Besides protecting vulnerable plant species, restricting the dispersal of dog feces in peri-urban areas protects grazing animals from zoonotic diseases and parasites.
Although our beloved pooches are innocent, they can nevertheless be a nuisance to the environment and the responsibility for protecting natural areas falls on us. In Europe and the United States, about 25% and 49%% of households own at least one dog, respectively. That’s a lot of dogs and consequently a lot of poop that needs to be disposed of properly.
The bottom of the Arctic Ocean is not the easiest of places to live in. Nutrients and vegetation are very scarce, it’s cold, it’s dark, the elements are pretty much against you. That’s why researchers were very surprised to find a dense population of sponges alive and kicking in the volcanic seamounts of the ocean. As it turns out, they were feeding off fossilized remains of extinct animals and fauna.
Image credit: The researchers.
Researchers from Germany’s Alfred Wegener Institute were around 200 miles from the North Pole on board their research vessel when a submarine camera they were towing caught sight of fuzzy sponges on top of the extinct volcanoes. They just couldn’t believe it. Some of the sponges even stretched over three feet (one meter) across — very big for sponge standards.
Sponges don’t have a digestive tract, so they rely on passive filter feeding to collect nutrients from water passing through them. Ocean currents in the Arctic Ocean are slow, with not many particles swirling in the water. This made the sighting even more unusual, especially considering tests showed the average sponge was 300 years old. How were they surviving there, for centuries, in what was basically an ocean wasteland?
Studying the sponges
The researchers collected samples of the organisms and the sediment around them and sent the samples to the lab for examination. The analysis showed the seafloor wasn’t as desolate as thought. In fact, the sediment samples were full of fossils.
The fossils were the empty shells of large deep-sea worms. While they don’t live there anymore, the researchers weren’t surprised to find the shells. Many years ago, gases leaked from the vents of the submerged volcanoes, creating a perfect habitat for the worms. That dynamic ecosystem from a long time ago is still influencing the area.
The samples collected suggest the sponges are packed with microbial bacteria, with which they form a symbiotic relationship. The bacteria break down the ancient leftovers that then the sponges use to obtain nutrients from. The researchers spotted different sizes of sponges, with the average measuring 30 centimeters or 12 inches.
“This allows them to feed on the remnants of former, now extinct inhabitants of the seamounts, such as the tubes of worms composed of protein and chitin and other trapped detritus,” said first study author Teresa Morganti, a sponge expert from the Max Planck Institute for Marine Microbiology in Bremen, Germany, in a statement.
The researchers believe that there could be more sponge grounds similar to this one along the volcanic ridge of the Arctic Ocean. This would be good news for many other creatures that live there because sponges are natural ecosystem engineers. As they grow, they create places for other animals to live in, depositing a sticky surface for bacteria to settle on.
A better understanding these ecosystems is essential to protect and manage the diversity of the Arctic Sea, which is currently under serious pressure, the researchers stress. With the sea ice retreating at record rates, the researchers want that the web of life in the Arctic Sea is under pressure. Both the sea ice and its thickness have shown a big decline, affecting the oceanic environment.
Last year, another group of researchers found sponges below the Antarctic ice shelves while drilling in the Filchner-Ronne Ice Shelf neat the southeastern Weddell Sea. It was an accidental discovery that left the researchers perplexed, calling for further studies (like this one) to better understand what’s actually going on below the Arctic Sea.
We’ve all heard the saying that one dog year is roughly equivalent to seven human years. But new research is working to find out more about how dogs progress through life — and, in turn, teach us about how we, ourselves, age.
Image via Pixabay.
It is true that dogs age faster than humans. However, according to researchers behind the Dog Aging Project (DAP), founded in 2018, the details are a bit murky. Saying that one human year is equivalent to seven dog years is a very broad simplification; big dogs tend to age the fastest, around 10 times as fast as humans, while little breeds age slower, about five times as fast as humans.
In other words, there is still much we don’t know about how man’s best friend grows old. Which is why the DAP was set up.
A dog’s life
“This is a very large, ambitious, wildly interdisciplinary project that has the potential to be a powerful resource for the broader scientific community,” said Joshua Akey, a professor in Princeton’s Lewis-Sigler Institute for Integrative Genomics and a member of the Dog Aging Project’s research team.
“Personally, I find this project exciting because I think it will improve dog, and ultimately, human health.”
The project is the largest undertaking to date that looks into canine aging and longevity. It currently involves tens of thousands of dogs of all breeds, sizes, and backgrounds, data from which goes into an open-source repository for veterinarians and scientists to use in the future. This wealth of data can be used to assess how well a particular dog is faring for their age, the researchers behind the DAP explain and help further our understanding of healthy aging in both dogs and humans.
It is set to run for at least 10 years in order to gather the data required. So far, over 32,000 dogs and their owners have joined the program, and recruitment is still ongoing. The owners of these dogs agreed to fill out annual surveys and take various measurements of their dogs to be used in the program. Some of them have also been asked to collect DNA material via cheek swabs for the researchers to sample. In addition, veterinarians associated with the program across the USA submit fur, blood, and other required samples from the dogs enrolled in the program (collectively known as the “DAP Pack”).
“We are sequencing the genomes of 10,000 dogs,” Akey said. “This will be one of the largest genetics data sets ever produced for dogs, and it will be a powerful resource not only to understand the role of genetics in aging, but also to answer more fundamental questions about the evolutionary history and domestication of dogs.”
The end goal of the program is to isolate specific biomarkers of aging in dogs. These should translate well to humans, the team explains. Dogs experience almost the same diseases and functional declines related to age as humans, veterinary care of dogs mirrors human healthcare in many ways, and dogs very often share living environments with humans. That last factor is very important as the environment is a main driver of aging and cannot be replicated in the lab.
Given that dogs share our environment, age similarly to us, but are much shorter-lived than humans, we have an exciting opportunity to identify factors that promote a healthy lifespan, and to find the signs of premature aging.
The oldest 300 dogs in the program will have their DNA sequenced as part of the ‘super-centenarian study. The team hopes to start this process in a few months. By that time, they will also open their entire anonymized dataset for researchers around the world to study.
If you live in the USA and would like to help, you and your doggo can enroll here.
The paper “An Open Science study of ageing in companion dogs” has been published in the journal Nature.
This photo shows a chimpanzee female, Roxy, applying an insect to a wound on the face of an adult chimpanzee male named Thea. Credit: Tobias Deschner.
In 2019, Alessandra Mascaro, a volunteer with the Ozouga Chimpanzee Project, was filming an adult female chimpanzee named Suzee, who was interacting with her little daughter Sassandra and adolescent son, Sia. Then, at some point, something very peculiar happened. As Suzee was inspecting a wound on Sia’s foot, the chimp mother dashed her fingers under a leaf, caught something which she put in her mouth, pressed it between her lips, then took it out of her mouth and applied it to the wound of her son’s leg.
That something turned out to be insects, part of a wound-tending behavior that turned out to be quite widespread among other members of Suzee’s group. Although Suzee wasn’t hurt herself, her actions indicate that she recognized Sia was in trouble and took action to help her son heal. It’s a remarkable display of prosocial behavior in a non-human species and a sign of empathy.
Self-medication is surprisingly common among animals
It’s not unheard of for animals to self-medicate. Birds, bees, lizards, elephants, and chimps know to ingest certain plants or use them in seemingly unusual ways when they need them. For instance, some lizards respond to a bite by a venomous snake by eating a certain root to counter the venom and baboons in Ethiopia eat the leaves of a plant to combat the flatworms that cause schistosomiasis. Amazingly, sparrows and finches collect nicotine-heavy cigarette butts to reduce mite infections in their nests, showing animals have learned to use pharmacological ingredients even in artificial environments.
But most examples of animal self-medication are documented among great apes. In 1996, American biologist Micahel Huffman first saw a parasite-ridden, constipated chimpanzee in Tanzania chew on the leaves of a noxious plant it would normally avoid. By the next day, the chimp seemed to have completely recovered.
Suzee’s family is an example of another form of self-medication. It’s the first time that researchers have seen chimps apply insects to themselves and others in order to treat wounds.
“We found out that there is a lot of research concerning self-medication, which is the use of secondary plant parts or other non-nutritional substances to medicate themselves. However, so far it was never observed that animals catch and apply insects to treat wounds and also treat the wounds of their conspecifics,” Simone Pika from the Institute of Cognitive Science at the Universität of Osnabrück told ZME Science.
Prosocial behavior among great apes
After studying Mascaro’s amazing video, Pika and colleagues from the Ozouga team decided to monitor the group of chimpanzees in Loango National Park in Western Gabon for other instances of this behavior. It wasn’t easy to find and follow the chimp community, which lives in challenging environments, including forests, savanna, beaches, and swamps. “In addition, there are also forest elephants around, which can be dangerous,” Pika said.
But the researchers rose to the challenge and, over the next 15 months, documented 76 cases of chimps applying insects to wounds on both themselves and others. We don’t know yet what type of insects were applied, nor what their medicinal properties could be but Pika says “there are many studies showing that insects have antibacterial, antiviral, anti-fungal, anti-inflammatory and probably also soothing substances.”
Most likely, the insects serve to provide some pain relief. The Ozouga researchers plan on conducting more research in order to identify the insects being used, as well as document who is applying insects to whom in the chimpanzee group. In the process, they may also learn more about how this behavior first started and how it’s transmitted among the members of the group.
“We know that the majority of our adult males and many females are using the behavior, suggesting that they have learned it. Furthermore, an insect application event always creates a lot of attention in the surrounding chimpanzees, meaning they all approach and want to look at what is going on,” Pika said.
But for the researcher, the most striking thing about this study is the prosocial nature of it all. Helping, sharing, and comforting are complex social behavior that benefits others rather than ourselves, and which we generally ascribe to humans. But if these findings are any indication, we are definitely not alone.
“There are still people doubting prosocial skills in other animals besides humans and I think this example is so clear that it will finally also convince the skeptics,” Pika said.
Asian elephants (Elephas maximus indicus) are by far the largest land mammal on the Asian continent, measuring up to 11 feet and weighing up to 5 tons. Their habitat covers 13 countries in South and Southeast Asia, but despite a relatively large spread, they are under serious threat from poaching and habitat destruction. To make matters even worse, there’s even a deadly virus threatening them. Now, a zoo in the UK wants to address this by working on a potentially life-saving vaccine for elephants.
Image credit: Wikipedia Commons.
Together with University of Surrey researchers, the Chester Zoo has long been looking at the Elephant endotheliotropic herpesvirus (EEHV), a type of herpes virus that can cause hemorrhagic disease when transmitted to young elephants. When the virus is detected in the blood or symptoms appear, it’s usually too late to treat the disease.
EEHV can affect any elephant, from young to adults. It’s known to have caused deaths in at least eight countries, including Nepal, Thailand, Cambodia, Laos, Myanmar, and Sri Lanka. Asian elephants are now listed are endangered by the International Union for the Conservation of Nature’s (IUCN), with all hopes placed on a vaccine solution.
The virus has been detected in zoos, sanctuaries, safari parks, and, more worryingly, in wild elephants. A study by veterinary scientist Sonia Jesus Fontes estimated that EEHV caused 52% of the deaths of Asian elephants in European zoos since 1985. In North America, the virus was accounted to have caused 50% of the deaths since 1980.
The team at Chester Zoo, including veterinarians, keepers, and immunologists, is now officially starting the trial of the vaccine, after long years of research. The backbone of the vaccine is the same as the one used to immunize elephants against the cowpox virus. Groups around the world have studied the EEHV virus but Chester Zoo is now taking a big step forward.
“The only long-term solution to beating EEHV is to find a vaccine. Without zoos caring for the species it would be almost impossible to achieve that but, thankfully, we’re now making remarkable progress. The global conservation community is today a step closer to finding a viable vaccine,” Mike Jordan, head of Animals and Plants at the zoo, said in a statement.
First steps of the vaccine
A healthy 20-year-old male elephant named Aung Bo is the first one to participate in the trials of the vaccine, with early tests showing an immune response. The trial was only possible due to the elephant’s willingness to participate. Vets test the elephants regularly for the virus, so they got used to providing blood samples on a regular basis.
Tanja Maehr, lead researcher at the University of Surrey, described this as an important moment in the team’s research, with “real optimism” to find a safe vaccine that works. While the initial results from the trials are positive, with the vaccine stimulating an immune response, these are still the early days on the road to an approved vaccine.
“It’ll be several months until the first stage of our work to select the best candidate vaccine and determine optimal dosages and frequencies is complete. Then, if successful, further trials in zoos and in the field will need to take place to fully ascertain its efficacy,” Maehr, also a conservation fellow at the zoo, said in a statement.
An impressive and ruthless predator, Komodo dragons are the largest living lizards on Earth. Their success is based on a very deadly bite, but there’s more than meets the eye to this endagnered, cold-blooded carnivore.
Image via Pixabay.
Reptiles used to rule the Earth, in the form of dinosaurs; today, they’re no longer top dogs. Some of their larger ancestors, such as crocodiles or alligators, bear hints of that fearsome legacy. Of others, such as lizards, for example, we tend to think of more as critters or cutesy pets basking under a heat lamp.
But not all lizards are born equal, and they can be quite fearsome creatures. The Komodo dragon (Varanus komodoensis) is living proof. Not only is it the largest, heaviest lizard on the planet, but the dragon is armed with vicious, shark-like serrated teeth and a potent toxic bite that bleeds its prey dry.
A living dragon
Komodo dragons are one branch of the monitor lizard family that is endemic to a few islands in Indonesia — they get their name from one of these, the island of Komodo, one of their prime habitats. They are the largest living lizards, growing up to 3 meters (10 ft) in length and approximately 70 kilograms (150 lb) of weight. Whichever way you cut it, that’s a lot of lizard. Wild specimens weigh around 70kg (150 lb), but those in captivity can weigh a lot more. The largest specimen officially found in the wild to date was 3.13 m (10.3 ft) long and weighed 166 kg (366lb), although that weight included an undigested meal.
The dragon’s tail is around the same length as its body, and they’re covered in very tough scales. Each scale is reinforced with a tiny bone (these are called osteoderms — ‘bony skins’), meaning that Komodo dragons are, essentially, encased in armor. Although such osteoderms are not unique to the Komodo dragons, they have been studied and described extensively in this species.
Their study was made possible by the Fort Worth Zoo, which housed the longest-living specimens bred in captivity, which lived for 19-and-a-half years. After its death, the zoo donated the body to the University of Texas at Austin, where researchers at the Jackson School of Geosciences examined it with a very powerful CT (computer tomography) device. The animal’s extensive age made for a well-developed, intricate, and striking suit of osteoderm armor.
Osteoderms, colored orange, cover the dragon’s body, as seen by this CT scan of its skull. Image credits The University of Texas at Austin / Jessica A. Maissano et al., (2019), The Anatomical Record.
The study revealed that the osteoderms in Komodo dragons differ in shape and overall coverage from other lizards — they’re more robust and cover more of the animal’s surface. A similar procedure on a baby Komodo dragon found no osteoderms, meaning that this bone skin develops as the animal becomes older.
Diet and behavior
As is befitting of a dragon, these lizards are top predators. They completely dominate their ecosystems, hunting and eating anything and everything from invertebrates to birds or mammals. They will happily eat carrion or other dragons, as well.
Their bite is vicious. Komodo dragons have serrated teeth that are ideal for ripping through flesh and bone. Their lower jaws house glands that secrete an anticoagulant toxin. This makes a bite from such a creature a very dangerous thing. When hunting, Komodo dragons bite down hard and pull back using powerful neck muscles; this tears flesh to shreds. The toxins then kick in to prevent clotting which leads to massive blood loss, sending their unlucky prey into shock.
Komodo dragons are not very active creatures, on account of their slow metabolism (a trait typical of most reptiles), so, most often, these reptiles rely on their camouflage and patience to pounce on unsuspecting prey. Despite their usual lethargy, Komodo dragons are capable of incredibly-fast strikes when hunting. Since they’re not very fast runners, their hunting strategy involves getting one good bite into their target, which virtually always escapes. Then, the dragons will calmly follow their victim, waiting for them to bleed out, using their keen sense of smell to follow the trail of blood. Such a hunt can take them miles away from the place where they delivered the bite.
But when they do happen upon the dead or dying prey, Komodo dragons feast in style. They can eat up to 80% of their body weight in a single feeding. This gluttonous nature, together with their slow metabolism, means that Komodo dragons in the wild typically eat only around once per month.
They are not above eating carrion, which they can detect using their sense of smell as far as six miles away. They are known for digging up graves in search of food. Komodo dragons can attack humans but only do so rarely.
An endangered species
First recorded by Western scientists in 1910, the Komodo dragon has never been an abundant species. Today, they are threatened with extinction as per the IUCN Red List. The main driver of their extinction historically was hunting for sport and trophy, with habitat destruction and climate change being the most pressing issues facing the species in modern times.
Komodo dragons are currently protected under Indonesian law. Authorities have gone so far as to temporarily ban tourist travel to the island of Komodo, and set up the Komodo National Park there in 1980 to aid in conservation efforts.
Such developments are especially surprising since female dragons can reproduce asexually — if no male is present, they can fertilize themselves. However, only males will result from such pregnancies. Combined with the Komodo dragon’s distaste from traveling far from their birthplace, this can quickly lead to inbreeding and collapse of isolated populations. Habitat destruction in the form of forest burning for agriculture leaves the species especially prone to inbreeding.
Billions of cigarette butts are discarded on Swedish streets each year, representing the most common type of littering in the Scandinavian country. Smokers leave this litter everywhere, from bus stations to narrow alleys. Since they’re so widely distributed across the entire city, clean-up is a never ending and expensive uphill battle. But this is where smart crows may come in.
Corvid Cleaning, a startup from Södertälje, near Stockholm, is on a mission to rid Swedish streets of annoying cigarette butts. To this aim, they’ve recruited some unlikely sanitation workers.
The startup is currently running a pilot program in Södertälje in which New Caledonian crows are trained to pick up butts off the street and deposit them in a special machine, which hands out a small food reward for every butt.
Crows are some of the most intelligent creatures in the world, not just of the bird kingdom. They use tools, which they’ve crafted themselves, to reach otherwise inaccessible food; remember people’s faces and even hold grudges; understand water displacement better than some human children, as well as the concept of zero, and solve highly complex puzzles involving intricate steps.
In comparison to their previous brainy feats, cigarette butt retrieval is easy pickings for these clever corvids. The startup founders are also banking on crows’ propensity for learning through observation when doing so benefits them, in this case by gaining easy access to tasty food. A handful of trained crows could turn into a swarm of cigarette butt-retrieving birds.
All the birds involved in this project are not being held in captivity, so they’re free to abandon the project at any time. For all intents and purposes, the crows are volunteering for this role.
If all goes well in this pilot program, the initiative could be extended to the whole of Stockholm, a city of nearly two million. It all hinges on how effective and financially feasible the program proves to be. Corvid Cleaning claims implementing the project across the city could cut cigarette butt cleanup costs by 75%.
“The estimation for the cost of picking up cigarette butts today is around 80 öre [Swedish change] or more per cigarette butt, some say two kronor. If the crows pick up cigarette butts, this would maybe be 20 öre per cigarette butt. The saving for the municipality depends on how many cigarette butts the crows pick up,” Christian Günther-Hanssen, the founder of Corvid Cleaning, told The Guardian.
A similar project was tested in 2017, in the Netherlands, and in 2018, at the Puy du Fou theme park in Western France.
It remains to be seen whether this creative plan will pan out as intended. In the meantime, we can’t help noticing that it is easier to train birds to pick up cigarette butts than it is for humans to learn not to discard them on the street.
Researchers have described two species of worms sporting a distinctive hammerhead look. The worms, discovered in parts of Europe and Africa, are likely invasive species and could wreak havoc on soil biodiversity.
Humbertium covidum, an invasive hammerhead worm found in Italy. Image credits: Pierre Gros.
As the world is becoming increasingly globalized, species are being brought from one part of the world to the other. These “alien” species have the potential to overrun the new ecosystem they’re brought to, and oftentimes, by the time you realize there’s a problem, there’s little you can do about it.
Oftentimes, you don’t even notice these invasive species unless you’re really paying attention — and this is exactly the case here.
An international team led by Professor Jean-Lou Justine from ISYEB (Muséum National d’Histoire Naturelle, Paris, France) described two new species of hammerhead flatworms. This is the first study of these species, although flatworms have been invading Europe for some time.
“We were surprised at first that some of the species which were invading Europe, a place where biodiversity is supposed to be well known, did not even have a name. That was the case of Obama nungara, a species described only in 2016,” Justine told ZME Science. The researchers did not give it a name at the time, though they did describe it in a 2020 paper with a charming title. The name Obama is formed by a composition of the Tupi words oba (leaf) and ma (animal), a reference to its body shape.
“This is also the case for the two new species described in this paper, they had no names and were never described in their countries of origin.”
Hammerhead worms are predatory creatures, much like their shark namesakes. They can track their prey (typically other worms or mollusks), and bear a distinctive shape on their head region, which helps them creep over the soil substrate.
Diversibipalium mayottensis, an invasive species of hammerhead worm found in Mayotte
A number of hammerhead worms have been described by scientists but, in many cases, the researchers don’t describe them in their land of origin, instead finding them in countries that they have already invaded. For instance, two previously described species (Bipalium pennsylvanicum and Bipalium adventitium) originate from Asia but were first reported from the US. The two newest species follow the same trend.
“I have been working on invasive land flatworms since 2013, when I discovered that gardens in France (and Europe) were invaded by bizarre worms and that almost no scientist was working on this problem. Leigh Winsor, the Australian member of our team, has been working on them since the 80’s,” Justine adds.
The first new species was named Humbertium covidum, as an homage to the victims of COVID-19, but also because much of the work was carried out during the COVID-19 lockdown.
“Due to the pandemic, during the lockdowns most of us were home, with our laboratory closed. No field expeditions were possible. I convinced my colleagues to gather all the information we had about these flatworms, do the computer analyses, and finally write this very long paper. We decided to name one of the species “covidum”, paying homage to the victims of the pandemic.”
The worm was found in two gardens in the Pyrénées-Atlantiques (France) and also in Veneto (Italy). Although some hammerhead worms can reach up to one meter, this one is small (3 cm) and looks uniformly metallic black — an unusual color among hammerhead flatworms.
These creatures are not easy to characterize based on their morphology alone, so researchers decided to use mitochondrial genetic analysis, which can provide a lot of information about the origin of this species and which other species it is related to. This species appears to have originated in Asia and is potentially invasive. By analyzing the contents of its stomach, researchers also found that it eats snails.
The second species, Diversibipalium mayottensis was only found in Mayotte (a French island in the Mozambique Channel, Indian Ocean). The species is as small as the other one, but instead of a metallic black, it exhibits a spectacular green-blue iridescence. Based on genetic analysis, this species appears to belong to a “sister group” of all other hammerhead flatworms, which means it could help researchers understand how these creatures evolved. Its origin could be Madagascar, but it’s not entirely clear. Presumably, at some point in the past, people brought plants from Madagascar and unknowingly, also brought the worm.
“All land flatworms are generally transported with potted plants,” Justine says. “For the species in Europe, Humbertium covidum, it is likely that the species was transported in recent years, from Asia, with some imported plant. For the species in Mayotte, Diversibipalium mayottensis, it is likely that it comes from Madagascar, but the transport might have happened a long time ago, perhaps even centuries ago, by traditional exchanges between islands in this part of Africa.”
Although finding new species is generally good news, this is not necessarily the case here. These flatworms are probably bad news, especially if they're not in their natural environment. For instance, one study found that one single worm species from New Zealand became invasive in the UK, and when it became established, earthworm biomass declined by 20%.
"All land flatworms are predators of the other animals of the soil fauna, and, as such, can threaten the biodiversity and ecological balance of species in a soil. However, there are only a very few papers in which their impact was thoroughly studied, because these studies are long and expensive," Justine explained in an email to ZME Science.
The study comes with a clear warning: invasive species are probably more prevalent than we realize. In the US alone, invasive species are estimated to cause damage of around $120 billion, and the figure is likely to increase as the world becomes more and more interconnected. Unfortunately, when it comes to dealing with invasive hammerhead worms, prevention is pretty much our only weapon.
"Basically, there is not much to be done once a land flatworm has invaded a country. Prevention is the key, we need to avoid importing new flatworms (that is true for Europe and US)," Justine concludes.
Green light-emitting diode (LED) lights can help protect wildlife from fishing nets, new research reports.
Image credits Paul Lee.
Affixing green LED lights to fishing nets can significantly reduce the catch of nontargeted animals such as sharks, squids, or turtles, according to a team led by researchers from the Arizona State University. The addition of these lights doesn’t impact the quantity or quality of desired catch species (i.e. commercially-available fish), which helps raise confidence that fisheries will adopt the measure. That being said, the installation of these lights comes with a significant upfront cost per net, which many fisheries may not be able to afford.
Beyond practical concerns, however, the findings showcase that it is possible to maintain our current fishing efficiency while insulating species that aren’t desired from capture.
Lights in the deep
Coastal fisheries routinely use gillnets, devices that resemble chain-link fences, to capture fish. These nets are deployed for up to several days at a time and capture virtually every kind of marine wildlife that cannot fit through their holes. Undesired captures (“bycatch”) are tossed overboard once the nets are recovered. These animals experience very high rates of death following this, adding up to significant pressure on marine species such as dolphins and sea turtles. It also impacts the fisheries’ bottom line, as personnel waste time removing these animals from the nets.
In other words, both business and nature lose out from the use of gillnets.
John Wang, a marine ecologist at the National Oceanic and Atmospheric Administration (NOAA), and his colleagues previously designed illuminated nets in order to protect turtles from becoming bycatch, back in 2016. Turtles seem to be particularly good at noticing green light, and these nets cut down on turtle bycatch by 64%. The current study builds on those findings, examining whether other marine animals could benefit from the same idea.
It turns out, they would. The authors worked with small-scale grouper and halibut fisheries in Baja California, Mexico, as the area is known for its large populations of turtles and other large marine species. They deployed 28 pairs of nets, one of each being equipped with groups of green LED lights every 10 meters. The team gauged their efficiency by identifying and weighing the animals each net captured overnight.
Nets outfitted with lights captured 63% less bycatch overall. Per species, they reduced bycatch by 51% for turtles, 81% for squid, and 95% for elasmobranchs (sharks and rays) — the last one being the most “gratifying” result for the authors, as shark bycatch in the Gulf of California is “a huge issue”.
Fish capture was not affected by the lights. However, the LEDs cut down on time wasted by fishermen on hauling and unloading bycatch, and on untangling the nets, by half. The only drawback so far, according to Senko, is the upfront installation costs of the lights: around $140 per net. Some fisheries, especially those in poorer areas such as Indonesia and the Caribbean, simply can’t afford this price per net, they add. The team is toying with using fewer lights and having them be solar-powered rather than battery-powered to reduce some of these costs. Meeting the needs of fisheries is essential for the success of this project, as they are the ones who will decide on using the LED nets or not.
Exactly why some animals seem to avoid lights, and why they do so more than others, is still up for debate. While it is possible that some species’ better eyesight helps them perceive the lights more clearly, it’s very unlikely that this is the cause — any species with sight can see these lights, after all.
The paper “Net illumination reduces fisheries bycatch, maintains catch value, and increases operational efficiency” has been published in the journal Current Biology.
