Tag Archives: worms

Worm species with three sexes found in Mono Lake

Mono Lake (California) is an inhospitable place for most life forms due to its super-salty waters, only known to be tolerated by bacteria, algae, and flies. Now, researchers have found worm species that thrive in the extreme ecosystem — and one of them has three sexes

Credit: Wikipedia Commons

Biologist Paul Sternberg and his colleagues at the California Institute of Technology thought that microscopic worms called nematodes might lurk in Mono Lake, partially because the wriggling creatures are considered the most abundant animals on the planet.

The team carried out a set of expeditions in 2016 and 2017 to the Mono Lake and found microscopic worms that can withstand 500 times more arsenic exposure than a human. The study was published in the journal Current Biology.

They unearthed eight nematodes that had a variety of mouth shapes. The distinct mouth on each worm may allow the creature to munch on its preferred diet. Some of the nematodes graze on microbes as cows do on grass, while others prey on animals. Other worms are parasites and leach nutrients from their chosen host.

“Previous species were isolated from rich soils and dung, which can contain high concentrations of phosphate,” the authors suggest. “Since arsenic uptake occurs adventitiously via phosphate transporters, it is conceivable that adaptation to high levels of phosphate in the environment could lead to increased arsenic resistance.”

One of the newly discovered species — for now called Auanema sp. — has not one, not two, but three different sexes, the team reported, and carry developing offspring inside their bodies. A look at the worm’s genetic code revealed a mutation in a gene called dbt-1, which helps break down the amino acids that makeup proteins.

Before this study, only two other species had been found in this lake — which is three times as salty as the ocean and has an alkaline pH greater than baking soda. Yet even so, the discovery of eight more species wasn’t all that surprising to researchers. Nematodes are the most abundant type of animal on the planet, so even in the harsh environment of Mono Lake, there’s a good chance you’ll find them.

“Our study shows we still have much to learn about how these 1,000-celled animals have mastered survival in extreme environments,” study co-author Pei-Yin Shih, a graduate student at Caltech, said in the statement

Worms Store Memories After Decapitation

Decapitated Worms Retain Memories – Transfer to Regrown Brains

land planarian, Bipalium kewense?

Imagine having your brain completely severed from your body, but being able to not only regenerate it – but also retain all information back into your newly regenerated brain.

That is impossible – right?

For humans the possibility is, indeed, impossible – but for the Planarians, it is their way of living and certainly not something out of a Kountry Kraft catelog.

The Planarians

Planarians, non-parasitic flatworms, have been trained and studied by biologists recently at a PA regeneration center. The fascination behind these worms lies within their impressive pluripotent stem cells. Unlike most creatures, Planarians contain an abnormal amount of these pluripotent stem cells, allowing for rapid regeneration. At an astounding 20-percent, pluripotent stem cells can take on the shape of any cell, which allows for the regeneration process.

In fact, the Planarians regeneration is so rapid that studies conducted in 1898 showed that even dissected to a tiny one 276th of its original size, the planarians could regenerate itself.

However, what makes these invertebrates even more spectacular was a recent study performed by Michael Levin, a Tufts University professor.

The Study

Published in the latest edition of the Journal of Experimental Biology, Levin conducted a study on Planarians cognitive functions and regenerative functions simultaneously.

Like many flatworms, or worms in general, planarians strongly dislike bright lights. They would much rather be in a warm, moist environment than a dry, hot one. Using this information, Levin vigorously trained his planarians to eat food in a very bright light.

Utilizing two different groups of planarians, Levin placed group 1 on a rigorous surface, while another on a flat surface. Each group had part of their environment illuminated by a light, where a piece of liver was placed.

Using a recording device, tracking analysis technology and measuring technology, Levin filmed the planarians over a ten-day period to see how easily each group would be to train. Those with a more rigid surface were more susceptible to the bright light and were less hesitant to eat in the bright light than those on a flat surface.

As a hypothesis, Levin suspected that if planarians were able to retain their memory after complete head severance, those on the rigid surface would be more susceptible to light exposure than those on the flat surface.

Analyzing this information, Levin severed all the heads on the worms and gave them a 14-day rest period to regrow their heads and brains.

The Results

Both group of worms were placed in a Petri dish and studied for their aversion to light. As suspected, both group of planarians were hesitant to go toward the light at first, however those who were on the rough terrain adapted much quicker.

Furthering his point, Levin then placed the planarians on a four-day break and placed them all back onto a Petri dish with light. Those on a rough terrain were much more susceptible to light exposure and moved around much more freely than those who were in the Petri dish.

This experiment provided Levin with the conclusion that the worms were able to retain their cognitive memory even after their heads were severed. At a minimum, planarians can retain memory for 14-days, enough to regrow their brains and restore the information.

How Their Memory is Stored

There is no definite answer as to how or where these planarians place their memories. It could be through their nervous system or through an unknown cellular memory function.

However, it is definite that planarians are able to store memories and regenerate all parts of their cellular body even when severed to a single miniscule portion.

Death pathway

Death occurs more slowly than thought, like a wave killing the body cell by cell

Death pathwayStudying death in humans has always been precarious. I mean, it’s not like anyone would volunteer to be live dissected as they slowly die, and even if someone would agree to such a procedure, most likely it would not be allowed. Not in any western hospital anyway. Luckily, death is such a common, as in inevitable, occurrence for all living beings that most animals models are good enough to offer insights into the analogous effects of death in humans as well.

With this in mind, a new study claims that death in  organisms, including humans, spreads like a wave from cell to cell until the whole individual is dead. What interesting enough is that the scientists from the Institute of Health Aging at University College London who made the study believe that this biochemical process may be halted and death may be delayed.

To study how death spreads throughout the body, the researchers chose to study worms, which oddly or ironically enough are considered immortal in the face of aging. Anyway, they’ve been proven to be very mortal in the present research and quite valuable too. A neat feature of worms is that when they die the underlying process that follows can be easily seen through magnification. As the organism dies, a  fluorescent blue light is released caused by necrosis, namely a molecule called anthranillic acid.  Apparently, this is dependent upon calcium signaling.

“A blue grim reaper…”

“We’ve identified a chemical pathway of self-destruction that propagates cell death in worms, which we see as this glowing blue fluorescence traveling through the body. It’s like a blue grim reaper, tracking death as it spreads throughout the organism until all life is extinguished,” David Gems from the Institute of Health Aging at University College London.

What this implies is that death doesn’t occur in the entire organism in an instant, but gradually propagates through out the entire body triggered by the death of vital individual cells, such as the case during a stressful event like a car accident or gunshot. This damage also happens, at a much slower pace albeit, when the individual ages.

Aged individuals are beyond hope and repair, according to the researchers, however if their trials on the worms offer in indications it’s that death could be “fooled” by stopping the calcium signaling biochemical spread of death under other non-aging-related circumstances.

“We found that when we blocked this pathway, we could delay death induced by a stress such as infection, but we couldn’t slow death from old-age,” Gems said. “This suggests that aging causes death by a number of processes acting in parallel.”

He continued that “the findings cast doubt on the theory that aging is simply a consequence of an accumulation of molecular damage. We need to focus on the biological events that occur during aging and death to properly understand how we might be able to interrupt these processes.”

Findings were detailed in a paper published in the journal PLoS Biology.

[source: Discovery]

Zombie worms found in whale fossil

As it turns out, zombies are not really only science fiction. Just a while ago I was telling you about a species of fungus that can turn ants into zombies, and how life on Earth may have actually originated from some ‘zombie aliens‘. Recently, researchers from the Natural History Museum in London have found evidence of millimetre-wide Osedax worms, which have never before been discovered in the Mediteranean.

Osedax worms, which means “bone-eating” in Latin have only been found in the Pacific off the coast of Washington state in the US and in the Atlantic off Sweden; until now, that is. Researchers are positive that they have found clear signs of Osedax ‘boreholes’ in a whale fossil; these zombie worms are one of scores of organisms which are provided for when whales die. Basically, when a whale dies, a whole new small ecosystem is formed, that literally feeds on the whale’s nutrients.

Nicholas Higgs, the project’s lead scientist, searched through bones from the 19th century explains:

“Fossils of worms are really rare. We don’t know a lot about their fossil record because they’re soft animals,” he said. “But, because these particular worms leave characteristic borings, we can trace them.”.

These worms are quite interesting organisms; they totally lack a mouth or intenstines, and instead they infiltrate the bones with some root-like organites to extract food. The findings can be found in Historical biology.

Via Telegraph

Devil worms live at 1.3 km beneath ground

Worms are definitely a tough bunch; you may see them as soft and vulnerable, but they can resist in conditions that would make even Les Stroud go ‘wow’. For example, a new study concludes that worms can live in up to 0.8 miles (1.3 kilometers) down.

The worms from hell

They have been rightfully named Halicephalobus mephisto in honor of Faust’s demon Mephistopheles – again scientists are finding some amazingly cool names. These worms are not only the record setters for worms, but they are the multicellular organisms living at the biggest depths.

“We tried to get the title of the paper to be ‘Worms from Hell,'” said study author Tullis Onstott of Princeton University. “But Nature didn’t go for that.”

Going deep

The team has been studying underground life for more than 15 years, focusing on the super deep mines in South Africa which go up to 3 kilometers in the bowels of the Earth. They had some quite interesting results, especially extremophile bacteria; but finding a 0.5 millimeters worm living in tiny holes and cracks – that’s a whole new different story. The worm lives in fluid filled holes, where it feasts of any bacteria that happens to be nearby.

“It’s kind of like finding Moby Dick in Lake Ontario,” he said. “It’s so volumetrically big. It’s 10 billion times the size of the bacteria upon which it feeds.”

In order to find the worm, the team studied water from mine boreholes that go up to 3.5 km deep. They also sampled about 40,000 gallons of surface water just to be sure that the worms (or nematods) weren’t coming from the surface.

Researchers were able to capture the species and make it reproduce in the lab, where it is still “squirming around”. The researchers also performed chemical analysis on the water, and found that it is at least 2900 years old, which means that the worms have been hanging around there for quite a while.

The team also tried to feed the worms some other bacteria, like E. Coli, but they found that the worms would much rather have bacteria from deep fissures, turning up its wormy nose.

Worms, everywhere worms

The finding encourages the search for life in some very different and extreme conditions; researchers assumed that any life they might find underground on Mars will be unicelullar, but this changes things quite a lot.

“This kinds of opens it up to, well, even multicellular life could be possible,” Meyer said.