Tag Archives: tool

Orangutans instinctively make and use basic stone tools

Loui (the juvenile male orangutan) using the core as an active element to vertically strike on the concrete floor of the testing room during the Flake Trading condition of Experiment 2. Image credits:

Orangutans are a crafty bunch. They seem to be able to use a bunch of tools in the wild and even make complex choices about these tools. So a team of researchers led by Alba Motes-Rodrigo at the University of Tübingen in Germany wanted to test their stone tool-making ability. The researchers tested out their hypothesis on two orangutans at Kristiansand Zoo in Norway.

“We wanted to investigate what stone-related behaviors might have served as stepping stones for the development of lithic technologies in our lineage. Extant apes (and monkeys) can be used as living models to build hypotheses in this regard,” Motes-Rodrigo tells ZME Science.

“We decided to test orangutans because despite being proficient tool users and using a variety of raw materials as tools, they do not use stone tools in the wild. This absence of stone tool use behaviors in the wild orangutan repertoire supports the naivety of our study subjects before the start of the experiments. This naivety allowed us to investigate the learning process of stone-related skills from the beginning, excluding previous knowledge of the tasks.”

Each orangutan was provided with a concrete hammer, a specially prepared blunt stone core, and two baited puzzle boxes. In order to get through the boxes, the orangutans had to cut through a rope or a silicon skin — but if they could do it, they got a treat.

Initially, both orangutans started hitting the hammer against the walls and floor of their enclosure. They didn’t strike the stone core directly. In the second experiment, they were also given a human-made sharp flint flake, which one orangutan used to cut the silicon skin, solving the puzzle.

It’s the first time cutting behavior has been observed in untrained, unenculturated orangutans. In a subsequent experiment, researchers demonstrated how to strike the core to create a flint to three female orangutans at another zoo (Twycross Zoo) in the UK. After being taught, one female went on to use the hammer to hit the core as demonstrated.

This suggests that two major prerequisites for creating stone tools (striking with stone hammers and recognizing that sharp edges can cut) may have existed in our common lineage with orangutans 13 million years ago. However, this is merely speculation at this point and we need more evidence before we can truly say whether this was the case or not.

“Our results have added a new piece to the puzzle of the technological origins of our species showing that an ape species that does not use stone tools in the wild and that diverged from our lineage 13 million years ago, spontaneously engages in stone-related behaviours crucial for stone tool making (lithic percussion) as well as has the ability to recognise and use sharp stones as cutting tools.”

“The lithic percussive behaviours that we observed seem to be relatively common among primates, with species such as macaques, capuchins and chimpanzees also expressing them in the wild and in some studies in captivity. The use of a sharp stone as a cutting tool had never been reported before in an untrained ape, but given that we only have one observation of this behaviour it would be premature to draw strong conclusions about its evolutionary history.”

Sharp-edged bits detached by the orangutan in the second experiment. Image credits: Motes-Rodrigo et al (2022).

The orangutans’ tool-making is remarkable, but they haven’t entered the Stone Age just yet, Motes-Rodrigo tells ZME Science. Essentially, their tools are not complex enough, and we haven’t seen them do this in a natural environment. They could be capable of doing it, but we haven’t observed them doing it. So, for the moment we can’t place them in the Stone Age just yet.

“Even the most primitive human stone tools were far more advanced than what we have seen in orangutans and reflect advanced spatial and cognitive skills. In addition, these behaviors have only been observed in captivity under experimental conditions. Perhaps if in future we would make similar observations in the wild, we could make such claims, but at the moment we can’t.”

Journal Reference: Motes-Rodrigo A, McPherron SP, Archer W, Hernandez-Aguilar RA, Tennie C (2022) Experimental investigation of orangutans’ lithic percussive and sharp stone tool behaviours. PLoS ONE 17(2): e0263343. https://doi.org/10.1371/journal.pone.0263343

Credit: Wikimedia Commons.

Capuchin monkeys are 3,000 years into their own Stone Age

Credit: Wikimedia Commons.

Credit: Wikimedia Commons.

Somewhere in Brazil’s remote Serra da Capivara National Park, stone tool technology has been refined and perfected for more than 3,000 years — but not by some tribe of humans. According to a 2019 study, bearded capuchin monkeys have been consistently using quartz stones to crack open cashew nuts, making the site the oldest non-human archaeological site in the world.

Since the past century, scientists have been aware that tool use is not an exclusively human trait. Many primates, for instance, use food-obtaining tools derived from sticks, which they employ in various creative ways. Chimps have been observed using sticks to smash fruit and some chimps have even been seen hunting bush babies with primitive spears that they thrust into the animal’s sleeping hollow. Some primates collect honey with sticks. Sumatran orangutans alone use up to 54 types of tools for extracting insects or honey.

Archaeological evidence suggests that chimpanzees in Côte d’Ivoire have been using stone tools to gain access to food for over 4,000 years. While not as old, recent digs in Brazil show that capuchin communities have adapted their tools over time. Researchers described over 122 capuchin stone artifacts of varying sizes and hardness — which cater to different types of foods — created over the course of 450 generations.

In other words, the capuchins in Serra da Capivara have their own archaeological record which traces back their antiquity. So, this is yet another trait that we’ve found is not unique to humans.

Understanding how capuchins have evolved in their tool use may reveal how other primates originally develop their own tool use, including our ancestors. Some of the oldest tools — deliberately flaked off rock projectiles and cutting tools — on the record are 3.3 million years old and are attributed to Australopithecus afarensis or Kenyanthropus platyops, two human ancestors. But before early human ancestors started to shape their own tools, scholars believe that they first used unmodified stone cobbles to process food, much like the capuchin in Brazil.

The oldest tools found at the site are relatively small and lightweight. Although these stones sustained a lot of damage from all the bashing, they did not exhibit any cashew stains (as seen today). But, something radically changed around 560 years or so ago, when the capuchin started wielding larger stones, implying they were going after harder foods. Finally, in the last 300 years, the capuchins have settled into an intermediate tool size and shape that is consistent with their current strategy of bashing cashew husks. This is evidenced by the telltale pockmarks on the rocks, stained brown from the cashew husks.

“We identify monkey stone tools between 2,400 and 3,000 years old and, on the basis of metric and damage patterns, demonstrate that capuchin food processing changed between ~2,400 and 300 years ago, and between ~100 years ago and the present day. We present the first example of long-term tool-use variation outside of the human lineage, and discuss possible mechanisms of extended behavioural change,” the authors concluded.

In other words, the tool use morphed to satisfy the capuchin’s diet. The researchers aren’t sure why their diet changed, but it could be that different groups of capuchin acquired a different taste for other foods. Alternatively, different plant foods appeared and disappeared in their area.

It’s quite remarkable to think about the fact that a non-human species is now fully in the Stone Age. Whether the capuchins can ever move into a more advanced stage of tool use is anyone’s guess at this point.

The findings appeared in the journal Nature Ecology & Evolution.

Puffins are now using tools — and it’s making them feel much better

Not only are puffins using tools, but the behavior is probably widespread.

More than just a pretty face: puffins were spotted using simple tools to scratch. Image credits: Richard Bartz.

As if puffins weren’t awesome enough, we can now add puffins to a select group of creatures: tool users. Specifically, puffins were spotted picking up sticks and using them to scratch their backs. It might not seem like much, but it suggests that puffins’ cognitive abilities are far more impressive than we gave them credit for.

It’s not the first time puffins would exhibit surprising qualities.

You wouldn’t think the puffin as much of a flier if you’d look at one. It’s not just the overall funky look: puffins have rounded bodies which don’t exactly scream ‘aerodynamic’ — nothing like the sleek shape boasted by many seabirds. But puffins can fly for hundreds of kilometers at a speed of up to 55 mph (88 km / h), beating their wings 400 times a minute. They also have an amazing ability to find their way home across thousands of miles and reunite with their mate.

In addition to their physical qualities, they now have the mental abilities to boast.

Researchers observed two puffins from separate colonies using wooden sticks to scratch their bodies. This is big news not just for puffins, but for seabirds in general, who were “previously thought to lack the ability, need, or opportunity to use tools,” researchers note. Sea-dwelling birds can now safely be added to the group capable of “body-care-related tool use.” Here’s one of the videos:

The two puffins spotted scratching themselves with tools were a part of different colonies: one was in Wales and the other one was in Iceland, over a thousand miles apart. This is either one big coincidence or, more likely, an indication that this behavior is widespread.

It’s also significant, researchers add, that puffins use tools for something else other than extracting food — one of the most common reasons why animals start to use tools. The fact that they use sticks for scratching, a rather low-importance (but oh-so-pleasant) task is quite remarkable.

It’s also notable that this is “true” tool usage — the object is detached from the substrate, as opposed to “borderline” tool usage, where the tool remains part of the substrate.

So far, the list of creatures capable of using tools is surprisingly short, and the list of creatures using tools for such trivial purposes is even shorter. This means some high praise for puffins is in order, but researchers also say that there’s a good chance many other species are using tools, but we just haven’t seen them yet.

The study has been published in PNAS.

Macaque tool-use patterns help us understand how early humans went about it

A new study on macaques at Thailand’s Ao Phang Nga National Park is helping us understand how early humans developed the use of stone tools.

Image credits Heiko S / Flickr.

Macaques tend to rely pretty heavily on stone tools, especially percussive (striking) tools, during their daily forage for food. This allows them access to more varied food sources — shellfish, in the case of the two groups of macaques that made the object of this study. The results indicate that while the environmental context definitely plays a part in tool use and development, cultural factors also matter.

Cracking oysters

“We observed differences among macaques on two different islands, in relation to tool selection and the degree of tool re-use when foraging for marine prey,” says co-author Dr. Tomos Proffitt from the University College London Institute of Archaeology.

The study assessed a total of 115 stone tools recovered from two islands (Boi Yai Island and Lobi Bay) located about 15 kilometers apart in southern Thailand, and are both part of the national park. Each island houses a population of wild long-tailed macaques, provides virtually the same tool-making resources (primarily limestone), and harbor the same prey species.

In such a context, the team expected both populations to develop similar, if not identical, tools. However, they found that the macaques on Boi Yai Island select heavier tools than their counterparts on Lobi Bay, while the latter’s tools show signs of repeated use on several species of prey.

Stone tools used to crack open oysters on Boi Yai tend to be larger than those used on Lobi Bay. While the team notes that oysters on Boi Yai Island are, in general, larger than those Lobi Bay, they believe that this is a learned rather than practical behavior.

“The theory is that if the environmental factors are the same—the only reasonable conclusion is that one island has developed its own tool using culture either through genetics or through passing down through a learning mechanism. While the other group exhibits a tool use culture which is more ephemeral and ad hoc,” says Dr. Proffitt.

Seeing how other primates develop and use tools today can help inform us about how our ancestors went about the same process. Lead author, Dr. Lydia Luncz (Institute of Cognitive and Evolutionary Anthropology, University of Oxford), said:

“That we find a potential cultural behavior in macaques is not surprising to us. The interesting part is that the same foraging behavior creates distinct tool evidence in the environment. This might be useful to keep in mind when we look at the archaeological record of human ancestors as well”.

The paper “Group-specific archaeological signatures of stone tool use in wild macaques” has been published in the journal eLife.

Tool.

Neanderthals used resin as glue to craft complex stone tools

Archaeologists have uncovered one of the oldest known examples of ancient humans using an adhesive.

Tool.

Image credits Ulrike Mai.

The study focused on two Italian caves that were inhabited by Neanderthals from about 55 to 40 thousand years ago. These people used tree resin to secure stone tools to shafts — a technological advance called “hafting” which revolutionized tool use. Members of the group would travel long distances from their caves to collect pine tree resin and then melt and apply it to glue stone tools to handles of wood or bone.

Sticky matters

“We continue to find evidence that the Neanderthals were not inferior primitives but were quite capable of doing things that have traditionally only been attributed to modern humans,” says Paola Villa, corresponding author of the new study and an adjoint curator at the University of Colorado Museum of Natural History.

The findings pool into a growing body of evidence suggesting that, far from being uncouth brutes, the Neanderthals were actually quite clever and ingenious. That insight comes from a chance discovery at Grotta del Fossellone and Grotta di Sant’Agostino, a pair of caves near the beaches of Italy’s west coast.

During the Middle Paleolithic (stone age) period, some thousands of years before modern humans set foot in Europe, these caves were inhabited by Neanderthals. Over 1,000 stone tools have been recovered from the two sites, including flint pieces that measured not much more than an inch or two from end to end. As they were studying these diminutive tools, Villa and her colleagues noticed a strange residue on a handful of them. These bits of material appeared to be organic in nature, which piqued the researchers’ curiosity.

“Sometimes that material is just inorganic sediment, and sometimes it’s the traces of the adhesive used to keep the tool in its socket” Villa said.

To find out, they carried out a chemical analysis of 10 flint pieces using gas chromatography/mass spectrometry — a technique that, basically, tells you the chemical make-up of a sample. The results suggest that the tools had been coated in resin taken from pine trees in the region; in one case, that resin had also been mixed with beeswax. Villa explains that, while most stone tools at this time were still hand-held, the Neanderthals in these caves did in some cases attach them to handles. This gave them better purchase for tasks such as butchering, scraping leather, or sharpening wooden spears.

This isn’t the oldest known evidence of European Neanderthals employing hafting, but it does suggest that the technique was more widespread than previously assumed. The findings also suggest that Neanderthals knew how to make fire and were able to start one whenever they wanted, just like their modern humans — something that scientists have long debated. She said that pine resin dries when exposed to air. As a result, Neanderthals needed to warm it over a small fired to make an effective glue.

“This is one of several proofs that strongly indicate that Neanderthals were capable of making fire whenever they needed it,” Villa said.

The paper “Hafting of Middle Paleolithic tools in Latium (central Italy): New data from Fossellone and Sant’Agostino caves” has been published in the journal PLOS ONE.

Prehistoric stone tools were invented multiple times before becoming a staple

A new archaeological site reveals that prehistoric stone tools were invented at least 2.58 million years ago, and were invented multiple times between 2.58 and 2.55 million years ago.

A large green artifact found in situ at the Bokol Dora site. Right: Image of the same artifact and a three dimensional model of the same artifact. David R. Braun.

The site in Ethiopia is called Bokol Dora 1, and is very close to where the oldest fossil of our genus was found in 2013. The fossil, a jaw bone, is important to our understanding of human evolution. It’s also 200,000 years older than the first evidence of flaked stone tools. Researchers have been trying to find a connection between these two elements, and now they finally have it.

The breakthrough came when Arizona State University geologist Christopher Campisano noticed some sharp-edged stone tools sticking out of the sediments on a steep, eroded slope.

“At first we found several artifacts lying on the surface, but we didn’t know what sediments they were coming from,” says Campisano. “But when I peered over the edge of a small cliff, I saw rocks sticking out from the mudstone face. I scaled up from the bottom using my rock hammer and found two nice stone tools starting to weather out.”

It took a few years to delicately excavate the sediments, a dig that exposed hundreds of animal bones and small pieces of stone tools. The site turned out to offer a trove of valuable archaeological data about how and when humans developed and started using stone tools. Remarkably, everything was in excellent shape — the site is close to a water source which quickly buried the remains in sediment.

“Looking at the sediments under a microscope, we could see that the site was exposed only for a very short time. These tools were dropped by early humans at the edge of a water source and then quickly buried. The site then stayed that way for millions of years,” noted geoarchaeologist Vera Aldeias of the Interdisciplinary Center for Archaeology and Behavioral Evolution at the University of Algarve, Portugal.

Kaye Reed, who studies the site’s ecology, also noted something interesting about these tools: they are very similar to those found a few kilometers away, although the environment is very different. There doesn’t seem to be any connection between these tools either, indicating that the invention was made on separate occasions, multiple times.

The overall picture is extremely complex, but it does seem that at some point around 2.6 million years ago our ancestors became more accurate and skilled at producing these tools, which are very different from the ones made by chimps or other animals. It was a crucial and defining moment in human evolution, paving the way for mankind’s emergence as a dominant species.

The study “Earliest known Oldowan artifacts at >2.58 Ma from Ledi-Geraru, Ethiopia, highlight early technological diversity,” has been published in the Proceedings of the National Academy of Sciences.

Ants craft tiny sponges to make it easier to carry food

“Ants are smarter than we give them credit for” is something we seem to write a lot – and yet it happened again.

Ants love their sweet liquids! Image credits: J. Coelho.

Tool use is something we consider reserved for intelligent species. It used to be that only humans were considered advanced enough to craft and use tools – but now we know better. Several species of apes and monkeys craft and use tools, even learning how to use them from humans. Elephants do it, as do some otters and of course, dolphins. Even some birds (most notably crows and ravens) have been observed using tools. It seems like several species of animals are much smarter than we gave them credit for – and ants are no exception.

István Maák, a researcher at the University of Szeged in Hungary, offered two species of funnel ants (Subterranea and Senilis)  liquids containing water and honey. Alongside, he gave them several tools that might help them carry food easier.

Firstly, the ants started experimenting. They were testing to see which tool was most effective. In the end, they settled for pieces of sponge or paper, which could absorb the honey better, making it easier to carry back home. The Subterranea workers (of the first species) used small soil grains to transfer diluted honey and sponge to transport undiluted honey. Many of them even tore the sponge into smaller bits, so they could better handle it. Meanwhile, Senilis first used all tools, and in time focused more and more on pieces of paper and sponge, which they used to soak up the honey.

There were previous indications of ants using tools, such as mud or sand grains, to collect and transport liquid to their nests, but this is special because the ants experimented with the materials not commonly found in their environment. Because they treated honey and diluted honey differently, this suggests that even without any previous experience with the materials, they accounted for the properties of both the tool and the material they were transporting. Also, they learned as they went and did so very fast. Valerie S. Banschbach at Roanoke College, Virginia, believes this is a testament to their mental proficiency – even if they have big brains.

“Many other accomplishments of these small-brained creatures rival those of humans or even surpass them, such as farming fungi species or using ‘dead reckoning’, a sophisticated navigation to find their way back to the nest,” Banschbach told NewScientist. “The size of brain needed for specific cognitive tasks is not clear.”

It’s likely that funnel ants developed this strategy and became better at tool handling because unlike many other ant species, they can’t expand their stomach, so they needed to find a better way of transporting things.

Journal Reference: István Maáka, Gábor Lőrinczi, Pauline Le Quinquis, Gábor Módraa, Dalila Bovet, Josep Call, Patrizia d’Ettorre. Tool selection during foraging in two species of funnel ants. http://dx.doi.org/10.1016/j.anbehav.2016.11.005

Critically endangered crow is highly skilled tool user

An international team has proved the mental prowess of a critically endangered species: the Hawaiian crow is really good at using tools.

Smart birds

A captive Hawaiian crow (‘Alalā) using a stick tool to extract food from a wooden log. ‘Alalā have relatively straight bills and highly mobile eyes — morphological features that may aid their handling of bill-held tools.
Credit: Copyright Ken Bohn/San Diego Zoo Global

For decades, the New Caledonian crow has baffled scientists with its ability to use tools. This species uses stick tools in the wild by finding small twigs and probing them into holes in logs to extract insects and larvae. They also manufacture tools by breaking twigs off bushes and trimming them to produce functional stick tools. They sometimes also exhibit meta-tool usage – they use tools to create other tools, something which requires very complex cognitive abilities.

These crows were considered an anomaly because no other corvid (crow) species exhibited such a developed intellect. But this new finding paints a completely different perspective.

“The exciting wider context is, if you have only a single species using tools, you’re trying to explain a singularity, and scientifically you’re not really winning with that,” said Christian Rutz, a behavioral ecologist at the University of St. Andrews and the lead author of the study. “But a second species provides leverage for cautiously asking evolutionary questions about how they evolved … and perhaps even to start speculating about the origin of tool use in humans.”

“I think the plot is thickening,” he added.

For over ten years, Rutz studied the New Caledonian crows. He showed that without anyone showing them how, the birds pick up twigs with their beaks and use them to scrape up food, a behavior not exhibited by any other bird species. With over 40 species of crows in nature, they seemed like the likely candidate… but which one? Crow species are generally understudied because most members live in small groups, in threatened or remote communities. Rutz couldn’t really afford to randomly fly and hope for something to happen.

But then, after a decade, he had his Eureka moment: unlike most species, New Caledonian crows have straight beaks. He performed a quick image search and found another species with the same characteristic – the large, all-black Hawaiian crow, known to Hawaiians as the ‘alalā.

Critically endangered

The ‘alalā is now sadly extinct in the wild but a last-ditch effort to preserve the species was somewhat successful. A few members still exist, in a breeding program in captivity. Without wasting much time, Rutz called the program manager, Bryce Masuda. It was a strange phone call.

“I said, ‘Look this may sound a bit crazy but I have a hunch your birds may be tool users,'” he recalled. “And the guy replied, ‘oh yeah, they do all sorts of funny things with sticks.'”

A captive Hawaiian crow (‘Alalā) using a stick tool to extract food from a wooden log. Virtually the entire species does this, without needing to be taught. (Ken Bohn / San Diego Zoo Global).

That’s when he knew he hit the jackpot. The Hawaiian crows had been using tools all along, but no one really understood – or if they did, they didn’t publish anything about this. Scientists working in the program told Rutz that they “had occasionally seen birds using stick tools at our two breeding facilities, but hadn’t thought much of it.”

After a quick observation period, they confirmed the theory.

“We tested 104 of the 109 ‘Alalā alive at the time, and found that the vast majority of them spontaneously used tools,” says Masuda. Current evidence strongly suggests that tool use is part of the species’ natural behavioural repertoire, rather than being a quirk that arose in captivity, according to Rutz: “Using tools comes naturally to ‘Alalā. These birds had no specific training prior to our study, yet most of them were incredibly skilled at handling stick tools, and even swiftly extracted bait from demanding tasks. In many regards, the ‘Alalā is very similar to the New Caledonian crow, which my team has been studying for over 10 years.”

Because so few ‘alalā survive at all, basically the entire species was studied. Many biologists expressed their compliments.

“Most studies in our field investigate just a handful of subjects, so it is truly mindboggling to see an entire species tested,” comments Professor Thomas Bugnyar, a corvid expert at the University of Vienna, Austria, who was not involved in the study.

Dark wings

In 1964, world-renowned primatologist, Dr Jane Goodall published a landmark paper in which she provided the first detailed report of tool use in wild chimpanzees. It was the first time a non-human species was shown to use tools. “Now we must redefine tool, redefine Man, or accept chimpanzees as humans,” she said. Two years after that, she also showed that Egyptian vultures use rock tools to open ostrich eggs. She was excited to hear about the new crow study and says we can already draw some comparisons between how primates and birds use tools

“I love learning about the discovery of tool use behaviours in other species of animals. This latest finding is especially wonderful. With two tool-using corvids, the well known Galapagos finches, and one vulture in the list of tool using birds, we can now make comparisons with avian and primate tool using. Each of these discoveries shows how much there is still to learn about animal behaviour, and it makes me re-think about the evolution of tool use in our own earliest ancestors.”

But the story isn’t necessarily a happy-ending one. As we said, the ‘Alalā is critically endangered – it’s extinct in the wild. Its reintroduction might be successful or it might fail, we don’t know. This means that one of the smartest creatures out there might be gone.

“Let this discovery serve to emphasise the importance to conserving these and other animal species so that we can continue to learn ever more about the range of their behaviour before they vanish for ever in the 6th great wave of extinction. We owe it to future generations.”

Chimp took down drone with careful planning

Calm and calculated – a chimp at a Dutch zoo took down a drone, squashing it with a tree branch. That’s pretty interesting (and a bit sad, if you’re the drone owner), but according to a paper published in the journal Primates, it may have more significance than it seems. According to the publishers, the chimp carefully planned the attack, just like a human would.

This year, on April 10, a Dutch film crew was using a drone to document a chimp enclosure at the Royal Burgers Zoo in Arnhem. However, the chimps didn’t like it, so some of them picked up branches from a nearby willow tree and two females, Tushi and Raime, climbed up on scaffolding to get closer to the drone and strike it, as you can see below.

“When the drone came a bit closer to the chimpanzees, a female individual made two sweeps with a branch that she held in one hand. The second one was successful and downed the drone. The use of the stick in this context was a unique action. It seemed deliberate given the decision to collect it and carry it to a place where the drone might be attacked. This episode adds to the indications that chimpanzees engage in forward planning of tool-use acts,” researchers write in the study.

They sent the drone smashing to the ground, and then looked at it for a while with inquisitive faces, before ultimately abandoning it. The footage went viral across the globe, but people missed a few important details. For example, when the female actually strikes the drone, you can see a grimace: her teeth were clenched and she was obviously tense, but she showed no signs of fear. This suggests that she acted on the drone not out of fear – but as a calculated move. In other words, she planned to attack it.

Prof Jan van Hooff, from Utrecht University, said: “The use of the stick as a weapon in this context was a unique action. It seemed deliberate, given the decision to collect it and carry it to a place where the drone might be attacked. This episode adds to the indications that chimpanzees engage in forward planning of tool-use acts,” Lukkenaar says, explaining the broader significance of the filmed event. This incident also shows the apes cautiously inspecting the contraption and even throwing it around before they lose interest in it.

To make things even more remarkable, chimps at the zoo were never really taught how to use weapons and tools, they just picked it up themselves. Previous studies showed that the chimps at this Dutch zoo spontaneously and innovatively use up to 13 types of tools in a variety of ways, especially with sticks (for example picking up fruits that are too high in the tree).

Journal Reference: Jan A. R. A. M. van Hooff , Bas Lukkenaar – Captive chimpanzee takes down a drone: tool use toward a flying object. (link)

Incredibly old tool found in Oregon

Archaeologists working in Oregon have uncovered a stone tool which seems to be way older than any previously documented site of human occupation in North America.

This June 6, 2013 photo provided by the University of Oregon Museum of Natural and Cultural History shows the Rimrock Draw Rockshelter archaelogical dig outside Riley, Ore. It is here that they found the tool now, in 2015. Photo: Patrick O’Grady, AP

When archaeologists date things, they use a relative law borrowed from geology, called the superposition law. The superposition law states that sedimentary layers are deposited in a time sequence, with the oldest on the bottom and the youngest on the top; in other words, the new stuff are at the surface, while the older things are buried more and more. But this law doesn’t always stand – especially in geology, many things can distort the natural setting, such as a volcano, a fault, or even just the movement of tectonic plates. Interestingly enough, in archaeology that law stands up more than geology, because we’re talking much thinner layers and much shorter periods of time (hundreds or thousands of years, as opposed to millions).

So when University of Oregon archaeologist Patrick O’Grady, who supervises the dig in Oregon, found a hand-held scraper chipped from a piece of orange agate he was ecstatic. Why? Because he found it under a layer of volcanic ash from an eruption of Mount St. Helens that has been dated to 15,800 years ago, which indicates that the tool is much older than that layer.

This undated photo provided by the University of Oregon Museum of Natural and Cultural History shows a scraper chipped out of agate found at an ancient rock shelter in the high desert of eastern Oregon. Photo credits: Photo: Patrick O’Grady, AP

There are two reasons to get excited about this: first of all, because the agate is not from the area – it’s not clear where exactly the agate was brought from, but it’s nowhere near the site; and second of all, the oldest known advanced human settlement in the area is the 13,000 year old Clovis culture.

“No one is going to believe this until it is shown there was no break in that ash layer, that the artifact could not have worked its way down from higher up, and until it is published in a convincing way,” he said. “Until then, extreme skepticism is all they are going to get.”

As a geologist, I do see some ways through which the tool may have been moved up, but it’s hard to emit a valid hypothesis without at least seeing the site. The first thing that comes to mind is a landslide, which may have relocated the tool and/or the ash layer. But if this is the case, you’d have to see all the higher layers also mixed up, so it should be fairly easy to notice. I can also imagine some scenarios where water carried it up, or more likely, where the tool was actually buried by someone who came around later. But who would bury it, or why? Those all questions which remain to be answered.

Crocodilians use sticks to attract prey

  • Two distinct groups of crocodilians have been reported to use tools for hunting
  • They balance sticks on their snouts, baiting birds who want to use the sticks for nests
  • Crocodiles actively search for the sticks (which are usually rare) and do this more often during the birds’ mating season

Mugger crocodile (Crocodylus palustris) at Madras Crocodile Bank, Tamil Nadu, India, with sticks on its head. Image credits: Dinets et al. (2013).

It’s been known for quite a while that the usage of tools isn’t restricted to humans. Monkeys (of course) also use tools, but this type of behavior has also been reported in other species, including crows, dolphins, elephants and otters. Now, a new study has reported that crocodiles and alligators also use sticks to attract prey.

In recent years, reptile research has provided some stunning results, showing that they are not only cold-blooded efficient killers, but that they exhibit a myriad of remarkable behaviors. Play behaviour, complex social interactions, gaze recognition, pair-bonding and monogamy, social hunting, speedy learning abilities and good memories – they have all been reported in reptiles.

Now, another very interesting unexpected adaptation has been demonstrated across these groups: tool usage.

As described by Dinets et al. (2013), Mugger crocodiles Crocodylus palustris in India and American alligators Alligator mississippiensis in the USA have been observed to lie, partially submerged, very close to birds they want to hunt, with sticks balanced carefully on their snouts. Birds want to take the sticks to use them in their nests and… let’s just say it usually has a very bad ending for the birds.

But what’s remarkable is that this occurrence of stick usage by crocodilians isn’t random! Stick displaying took place consistently more often with crocodiles living closer to rookeries, and it also took place more often during mating season – when birds are more inclined to construct nests. It’s also noteworthy that sticks are pretty rare in this type of environment – the reptiles actively search for them, especially during the birds’ mating period.

Baiting behavior was demonstrated before in archosaurs (the big group of species which includes crocodiles, birds and all extinct dinosaurs). Green herons (Butorides virescens) often do it: they use feathers, twigs and even berries and bits of bread to attract fish, while burrowing owls (Athene cunicularia) use mammal dung to attract dung beetles. Also, anecdotal reference suggests that crocodiles also use fish fragments to attract birds. But the fact that this has been consistently reported in two separate groups seems to suggest that this type of behavior is mainspread.

If you think about it, crocodiles have been around for over 70 million years – since the Cretaceous. They are incredibly well adapted to the environment, being able to live as scavengers and survive for months without food. They can even go into a state of hibernation when conditions aren’t favorable, waking up when things are looking up. So it makes sense that they learned a trick or two about hunting.