Monkey Tool Users

You may have never heard of a bearded capuchin monkey.  In many ways it is a typical New World monkey.  However, this particular species of monkey continues to impress primatologists because it is the only known non-ape primate to use tools.  Primatologists “discovered” this in the 1990’s, but knowledge of capuchin monkey tool-use has been a part of Brazilian folklore for over four centuries, if not longer.

Although more research needs to be conducted, it appears as though they have a limited “tool-kit” consisting of specialized stones that they use to crack nuts in different savanna-like environments (Ottoni & Izar, 2008).  Interestingly, there is a high degree of intentionality in both the stone selection process, and in the strategic use of stone tools (Visalberghi et al., 2009).  Furthermore, a paper published a few days ago revealed that they have the capacity to improve the efficiency of their tool use (Fragaszy et al., 2013). Here is an awesome video via the BBC of a capuchin using a tool to crack open a nut:

What is perhaps more remarkable, is that the capuchins lower skeletal structure is well adapted to walking bipedally while carrying stones.  This could mean that stone tool use has been an integral part of the bearded capuchin’s behavioural repertoire for thousands of years (if not much longer).

So what do these discoveries mean?  In terms of primate tool-use they appear to be an extreme phylogenetic outlier.  Chimpanzees, bonobos, gorillas, and orangutans make and use tools, but the lesser apes and all other monkeys in the wild do not.

When considering the fact that all great apes make and use tools, it seems reasonable to suspect that the common ancestor of all great apes also made and used tools.  That pushes back the origin of primitive tool use to perhaps as late as 14 million years ago.  Of course, as Adam Benton of EvoAnthhas pointed out, the first empirical evidence in the paleoanthropological record of stone tool construction is 2.5 million years old.  But the nature of the paleoanthropological record is fragmentary and all great ape tools would not preserve archaeologically; therefore it is also important to consider the possibility of tool-use being ancestral for great apes.

But where do the bearded capuchins fit into this picture?  These primates are displaying a type of technological ability that was thought to have emerged approximately 2 million years ago with the origin of our genus.  Is this simply an extreme and unexpected example of convergent evolution?

Capuchin stone tool-use wouldn’t represent the first time that animal behaviourists have been surprised by cultural and technological diversity in the animal kingdom.  Over the past few decades anthropologists and biologists have uncovered an unprecedented amount of cultural variety among cetaceans and birds, including New Caledonian crow tool use that appears to be cumulative (Hunt & Gray, 2003).

In my initial judgment of this perplexing situation, I would lean towards accepting the parsimonious conclusion: that capuchins have convergently evolved the ability to use stone tools.  However, some researchers have proposed that we must not rule out the alternatives.  It could be that stone tool-use among primates emerged 35 million years ago, with the origin of the first monkey species.  Or it could be the case that stone tool use has been adapted and then lost by several monkey and ape species over the past 35 million years.  If either of these scenarios is true, we must explain why all other known contemporary monkeys have no stone tool kits.

Either way, this is yet another great example of animals forcing us to question our relationship to the past and our own divergent behaviour.

Love evolution?  You can find more of Cadell’s thoughts on evolutionary anthropology via Twitter!


Dean, L.G., et al.  2012.  Identification of the social and cognitive processes underlying human cumulative culture.  Science, 335: 1114-1118.

Fragaszy, D.M., Liu, Q., Wright, B.W., Allen, A., & Brown, C.W.  2013.  Wild bearded capuchin monkeys (Sapajus libidinosus) strategically place nuts in a stable position during nut-cracking.  PLoS ONE, 8: e56182.

Hunt, G.R. & Gray, R.D.  2003.  Diversification and cumulative evolution in New Caledonian crow tool manufacture.  Proceedings of the Royal Society, 270: 867-874.

Ottoni, E.B. & Izar, P.  2008.  Capuchin monkey tool use: Overview and implications.  Evolutionary Anthropology, 17: 171-178.

Visalberghi, E., Addessi, E., Truppa, V., Spagnoletti, N., Ottoni, E., Izar, P. & Fragaszy, D.  2009.  Selection of effective stone tools by wild bearded capuchin monkeys.  Current Biology, 19: 213-217.

Related Advanced Apes content:

Universality of Preadaptation for the Human Condition

The Evolution of Primate Sleep

Diurnality, Nocturnality, and Cathemerality


Asteroid Apocalypse?

Of course we are not as vulnerable today as we were 70,000 years ago.  Our population has ballooned to 7 billion and we inhabit nearly all-terrestrial niches on the planet.  We are an interconnected global faunal hegemony the likes of which have never been seen before on our planet.  However, the great astronomer Carl Sagan still worried.  He said that theoretical future humans would “marvel at how vulnerable the repository of all our potential, once was.”

Asteroid Apocalypse

This week theoretical physicist Dr. Michio Kaku tried to make our vulnerability apparent. He wrote an article for Newsweek titled “Asteroid Apocalypse.”  Within it he explores our recent history of asteroid encounters, including our near miss with DA14 (an apartment sized asteroid that grazed Earth last week).  An Asteroid the size of DA14 is what Dr. Kaku calls a “city buster,” capable of wiping out an entire metropolis if they hit in the right area.  However, he warns that in our solar system there are asteroids far larger, like the asteroid Apophis, which is on a trajectory near-Earth and could strike our planet with as much force as 1,000 Hiroshima bombs.

Luckily for us, it appears as though Apophis will miss Earth in 2029 and 2036.  NASA scientists have calculated that there is only a 1 in 140,000,000 chance of a collision.

Dr. Kaku is definitely not wrong to warn us of the asteroid dangers in our solar system.  There are over 8,000 known near-Earth asteroids, and probably several thousand more that we are currently unaware of.  It is important that everyone knows and understands the dangers that these asteroids pose to our civilization and our species.  But from what we know, there is nothing on a collision course with Earth that poses any serious threat of an apocalypse.  Apophis will not bring darkness and chaos, like the Egyptian god it is named after.  Instead, Apophis represents a great way for us to learn different asteroid-deflection methods so that we are prepared for one that is actually on a collision course with our planet.

In my mind, all of this information leads me to conclude that after our tests with Apophis, we will be able to knock another threat off our list of extinction concerns.  If we are able to alter the future trajectory of Apophis, it stands to reason that we would be able to do the same with any future asteroid that was actually on a collision course with our planet.

I know the title “Asteroid Apocalypse” is just a product of sensationalist journalism, but it is also irresponsible misinformation.  Current data indicate that if apocalypse ever comes, it will not likely be from the skies.  After all, we inhabit an enviable area of space-time in the quiet suburbs of the Milky Way.

The Century of Great Ape Culture

In the past, I have discussed some of the biggest chimpanzee culture discoveries in The Ratchet.  Many of these discoveries were made in the 20th century.  This culminated in 1999 with a behavioural synthesis of 20th century chimpanzee cultural data throughout Africa (Whiten et al. 1999).  This research stimulated other primatologists to test whether cultural behaviour was exhibited within other great ape species.  As a result of this research, the 21st century has been a century of great ape culture discovery.  These discoveries are forcing us to reconceptualize our understanding of the great apes and ourselves.  There is no more question of whether our closest relatives are cultural, the focus has shifted to understanding the evolution and variation of cultural behaviour.

There have been far fewer studies conducted to understand cultural behaviour of bonobos, orangutans, and gorillas vis-à-vis chimpanzees.  Gorilla culture is perhaps the least understood.  Most of our knowledge of gorilla culture comes from a groundbreaking study by primatologists Thomas Breuer, Mireille Ndoundou-Hockemba, and Vicki Fishlock, revealing that gorillas make tools that are partially inspired by ecological problems they face in certain habitats (Breuer et al., 2005).  The team reported two interesting cases of gorilla tool use:

a) An individual utilizing a branch to test water deepness and stabilize herself during a river crossing

b) An individual using a trunk from a small shrub as a bridge to cross a deep swamp

This study shows that we may have a lot more to learn about gorilla culture.  Unfortunately, gorillas are extremely difficult to study in the wild.  There are entire subspecies of gorilla that have never really been observed at all. For researchers, this makes understanding gorilla culture and cultural variation almost impossible.  However, new motion-sensor camera traps are enabling scientists to design research studies that were impossible just a few years ago.  It is possible that future research designed with these camera traps could allow us to learn more about gorilla culture.  The 2005 paper by Breuer et al. (2005) makes me excited for the possibility of such a study.

Bonobos have been slightly less mysterious than gorillas.  A study by Gottfried Hohmann and Barbara Fruth in 2003 partially uncovered the cultural world of our other most closely related relative.  Hohmann & Fruth were inspired by the “Cultures in chimpanzees” study by Whiten et al. (1999) and wanted to know how many of the cultural variants described in chimpanzees were also present within Lomako’s bonobo population.  By analyzing behavioural data between 1991 and 1998, they revealed that 14 cultural variants in chimpanzees are also present in bonobos.  These include branch drag, leaf sponge, branch clasp, vegetation seat, aimed throw, and the hand clasp (Hohmann & Fruth, 2003).  Although the study sample was considerably smaller than the one used by Whiten et al. (1999), this study raised the possibility that chimpanzees were more culturally complex than their sister species (Tennie, et al., 2009).  If true, the implications of such a discovery would raise some interesting questions about the evolution of culture and the behaviour of our common ancestor with chimpanzees and bonobos.  However, these results could also simply be a product of the fact that there are more chimpanzees that inhabit a wide and diverse number of ecological niches.

Finally the orangutan, the lone Asian great ape, has also provided researchers with impressive evidence of cultural behaviour and variation.  In fact, the geographic variation of cultural traditions among orangutans may most closely parallel those observed in chimpanzees.  In 2003, Carel P. van Schaik and a team of researchers revealed that there was a strong correlation between geographic distance and cultural distance among orangutan populations (van Schaik et al., 2003).  Surprisingly, this correlation may even be stronger than that observed among chimpanzee populations throughout Africa (Tennie et al., 2009).  Also, orangutan tool use has proven to reveal some of the most unique functions in the entire animal kingdom, including autoerotic tool-use, leaf napkin, branch swatter, seed extraction tool-use, sun cover (building a cover for a nest on bright sunny days) and branch scoop (drinking water from a deep tree hole using a leafy branch) (van Schaik et al., 2003).

Of course, all of these data indicate that many 20th century academics were wrong about culture being a defining aspect of our species.  Culture appears to be ubiquitous among the great apes, and widespread throughout the animal kingdom.  There is now evidence for large-scale patterning of culture within and between populations, and entire communities appear to possess suites of cultural behaviours (Whiten et al., 2003).  Furthermore, just like humans, culture allows the great apes to flexibly shape their environment (Breuer et al., 2005), gain access to resources (Sanz & Morgan, 2009), develop subcultures (Boesch, 2003), and share meaning (e.g., Hohmann & Fruth, 2003).

The fact that culture is present in all great apes increases the likelihood that the capacity for culture within our lineage may have been present as late as 14 million years ago (van Schaik et al., 2003).  And studies on some monkey species have suggested that it could have been present as early as 35 million years ago (Visalberghi et al., 2009).  However, despite the fact that modern primatological inquiry has revealed startling similarities between human and great ape culture, more research needs to be done in order to understand the mechanisms that enable novel behaviours to be learned (Hrubesch et al., 2009).

Also, if we are not the only cultural species, what makes us so different?  I have hinted at what primatologists have learned about this perplexing question, and I will be exploring those ideas in great detail in the near future.

If you engage in the cultural tradition of using Twitter, follow Cadell for more primate-related info!

Also posted via Svbtle:


Boesch, C.  2003.  Is culture a golden barrier between human and chimpanzee?  Evolutionary Anthropology, 12: 82-91.

Breuer, T., Ndoundou-Hockemba, M. & Fishlock, V.  2005.  First observation of tool use in wild gorillas.  PLoS ONE, 3: e380.

Hohmann, G. & Fruth, B.  2003.  Culture in bonobos?  Between-species and within-species variation in behaviour.  Current Anthropology, 44: 563-571.

Hrubesch, C., Preuschoft, S., & van Schaik, C.P.  2009.  Skill mastery inhibits adoption of observed alternative solutions among chimpanzees (Pan troglodytes).  Animal Cognition, 12: 209-216.

Sanz, C.M. & Morgan, D.B.  2009.  Flexible and persistent tool-using strategies in honey-gathering by wild chimpanzees.  International Journal of Primatology, 30: 411-427.

Tennie, C., Call, J., & Tomasello, M.  2009.  Ratcheting up the ratchet: on the evolution of cumulative culture.  Philosophical Trasactions of the Royal Society.  364: 2405-2415.

van Schaik, C.P., Ancrenaz, M., Borgen, G., Galdikas, B., Knott, C.D., Singleton, I., Suzuki, A., Utami, S.S., Merrill, M.  2003.  Orangutan cultures and the evolution of material culture.  Science, 299: 102-105.

Visalberghi, E., Addessi, E., Truppa, V., Spagnoletti, N., Ottoni, E., Izar, P. & Fragaszy, D.  2009.  Selection of effective stone tools by wild bearded capuchin monkeys.  Current Biology, 19: 213-217.

Working on Working Memory

Several years ago, I remember being amazed by a video of a chimpanzee named Ayumu from Kyoto University’s Primate Research Institute.  Ayumu appeared to be an incredibly gifted individual with the ability to recall Arabic numeral sequences with remarkable speed and accuracy on a computer touch screen.  When Kyoto University primatologists released their study based off of Ayumu and other chimpanzees titled “Working memory of numerals in chimpanzees” (Inoue & Matsuzawa, 2007), they made headline news and stimulated intense debate in academic and popular science circles.  This debate was not centered around the specific memory capacities of the chimpanzees, but instead around the fact that the chimpanzees out performed all of the humans in the study.

In the study juvenile chimpanzees could recall the position and order of a random set of five Arabic numerals between one and nine with approximately 79% accuracy, after being exposed to the numerals for 210 ms.  None of the nine humans in the study reached this level of accuracy.

The feat was thoroughly impressive.  Like most people who watched the video, I thought to myself, do chimpanzees have a better working memory than humans?  Tetsuro Matsuzawa, one of the lead authors of the study, claimed that they did.  In fact, he further added that his study revealed that chimpanzees possessed a mental capacity that humans beings had lost over evolutionary time.

Some evolutionary theorists proposed that there may have been a trade-off in our development between language and memory.  Others proposed that enhanced chimpanzee memory was likely an adaptation to their environment that was unnecessary for our hominid ancestors.  However, it was clear that more hypotheses needed to be tested before we could know for sure.

As a result, Inoue & Matsuzawa’s study was analyzed.  Primatologists at other research labs wanted to replicate their methodology to confirm the finding that chimpanzees possessed a stronger working memory than adult humans.  There would be massive implications for evolutionary theory and our understanding of human evolutionary history.

Unfortunately, it did not take a long time for controversy to surface.  Siberberg & Kearns (2009) discovered that the Inoue & Matsuzawa study was critically flawed.  Ayumu and the other chimpanzees had had several sessions of practice on their task and none of the nine human participants had had any practice sessions.  This difference in the level of practice before the testing appears to explain the difference in skill.  Importantly, Siberberg & Kearns (2009) presented data that showed humans could perform at the same level as Ayumu when given even moderate levels of practice.

However, the damage had effectively been done.  The Inoue & Matsuzawa study had become so popular in both the academic and popular press that most people accepted the idea that chimpanzee working memory was superior to modern human working memory.  This effected future research studies, like the paper “Did working memory spark creative culture?” (Balter, 2010).  Within this paper it is proposed that a trade-off between language and working memory in our evolution sparked the cultural revolution between 200,000 and 40,000 years ago.  Of course, this theoretical proposition had no grounding in empirical fact since it reported “chimpanzees are better than humans at some memory tasks” based on the Inoue & Matsuzawa (2007) study (Cook & Wilson, 2010).

And the myth also continued to persist in the popular press.  In 2012, several different online news sources ran specials on the Kyoto chimpanzees, and a BBC documentary titled “super smart animals” included video of Ayumu and emphasized her “superior memory abilities”.

Back within academia, the studies methodological flaws were becoming well known thanks to two papers: “In practice, chimp memory study flawed” by Peter Cook & Margaret Wilson (2010), and “This chimp will kick your ass at memory games – but how the hell does he do it?” by Nicholas Humphrey (2012).

In the latter article, published in Trends in Cognitive Science, Humphrey reveals some critical backstory that can explain the skills of the Kyoto chimpanzees.  Humphrey explained that the Kyoto chimps had been trained to touch and memorize Arabic numerals in random position for nearly a decade before the now controversial 2007 study.  Ayumu had managed to reach perfection by 2011.  When shown nine numerals for just 60 ms she could now reach perfect accuracy.  As impressive as this is, a decades worth of practice was a significant variable to consider.

However, Humphrey proposed yet another interesting possibility for Ayumu’s working memory skill: synaesthesia.  In the most common form of synesthesia, letters and numbers are perceived as inherently coloured.  For humans, this form of synesthesia significantly improves an individual’s ability to recall the order of arbitrary symbols like numbers.  If Humphrey is right, then the chimpanzees in Matsuzawa’s lab may be touching what to them looks like colours belonging to a well-known sequence, as opposed to what they look like to us, blank white squares (Humphrey, 2012).  Future research still needs to be conducted to see if Humphrey’s hypothesis is correct.


Within a span of five years, research on chimpanzee short-term memory has become one of the most controversial areas of inquiry within science.  And that is why I was surprised to see that Tetsuro Matsuzawa decided to showcase Ayumu and the now infamous short-term memory experiment this week at the Association for the Advancement of Science (AAAS).  In the video demonstration, Ayumu performed the 1-9 number sequence experiment, and also was shown to have now learned numbers 1-19.  The popular press has once again used this demonstration to conclude that chimpanzees incredible short-term memory is superior to humans, and is vitally adaptive.  Of course, within academia this is not the current consensus, as I have explained above.

I think what I have learned from following and researching this ongoing drama is that the popular scientific press has an incredible power and responsibility.  For science writers and bloggers that care deeply about scientific discourse, we must make sure that we continue to do exceptional research and remain critical.  If we passively regurgitate we will only perpetuate myth and pseudo-science.  And that cannot benefit future scientific inquiry.

Want to learn more about chimpanzees?  Follow Cadell Last on Twitter!


Balter, M. 2010. Did working memory spark creative culture?  Evolution of Behavior, 328: 160–163.

Cook, P. & Wilson, M. 2010. In practice, chimp memory study flawed. Science, 328: 1228.

Humphrey, N. 2012. ‘This chimp will kick your ass at memory games – but how the hell does he do it?’Trends in Cognitive Science, 16: 353–355.

Inoue, S. & Matsuzawa, T.  2007.  Working memory of numerals in chimpanzees.  Current Biology, 17: R1004-R1005.

Siberberg, A. & Kearns, D. 2009. Memory for the order of briefly presented numerals in humans as a function of practice. Animal Cognition, 12: 405–407.

What Is It Like to Be a Bat?

In 1974, philosopher Thomas Nagel wrote a paper that became an instant classic within academia: What Is It Like to Be a Bat?  Within this paper Nagel contends that although consciousness probably occurs in countless forms on our world and elsewhere in the universe, the fact that an organism is conscious at all means that there is something it is like to be that organism (Nagel, 1974).  It is a strange thought.  But is it at all possible to truly understand the internal subjective experience of another organism?

Well, how do bats navigate their world?  What do they do?  How do they live?  This was the initial thought process Nagel used to attempt to understand what it was to be a bat.  He imagined flying with webbed arms, trying to catch insects, and hanging upside down in an attic or cave.  He then attempted to understand their perception of the world. Most bats navigate their world using echolocation.  Echolocation is a type of biological sonar that allows bats to detect reflections from objects within their range using their own modulated shrieks.  They use it for travel and also to forage.  Of course, this perception is not at all similar to how humans navigate their own worlds.  Nagal concluded that:

“In so far as I can imagine this (which is not very far) it tells me only what it would like for me to behave as a bat behaves. But that is not the question. I want to know what it is like for a bat to be a bat.”

— Thomas Nagel

Since bats actually utilize a form of perception alien to a human, perhaps that explains why it is we can’t really know what it’s like to be a bat.  As a primatologist, I have spent countless hours observing primates (specifically chimpanzees and ring-tailed lemurs).  However, I will concede that even though I can explain their behaviour to someone, I can’t really understand what it is like to subjectively be a chimp or a lemur.  Lemurs primarily understand their world through olfactory perception.  Since I am primarily an audio-visual animal, I really don’t understand what it is like to understand my world through the sense of smell.  Another big obstacle in this thought-experiment is the fact that I think with language.  We all think with language and no other animal does this.  It would be incredibly hard to train my mind to think in a way that isn’t organized in some way by a linguistic narrative.  I also have a massively enlarged neocortex.  This makes it really impossible for me to imagine the differences in my thought processes enabled by that neocortex vis-à-vis a chimps (for example).

Perhaps in the future technology could help us understand other animal’s subjective experience?  Would it be possible to design a technology that enabled us to experience biological sonar or mimicked the olfactory capabilities of a lemur?  I believe Nagel would agree with me that this still doesn’t solve the problem of knowing what it is like to actually be that animal.  This is because other animals may have fundamentally different types of consciousness.  Perhaps consciousness itself has had different evolutionary trajectories throughout the organic world that we are currently unaware.  In this scenario, reductively understanding and mimicking our biological differences with them would do little to help us understand subjective conscious experience.  I personally think that we will never know what it is like for a bat to be a bat; we will only ever know what it is like for a human to imagine what it is like to be a bat.

Interestingly, geneticist George Church tackled this problem in his recent book Regenesis.  However, instead of attempting to understand what it is like to be a bat, he wanted to know what was like to be a cell.  In order to do this Church explained how nucleic acids (DNA and RNA), proteins (the cell’s housekeepers) and the lipid bilayer membrane function within a complex system (Church, 2012).  He concluded:

“To be a cell, then, is to be a deterministic system governed by DNA, composed largely of proteins and lipids, and energized by ATP.”

— George Church

Church is sort of cheating the philosophical question raised by Nagel in this example because, of course, a cell is not conscious.  The problem Nagel encountered was not in explaining how a bat functions or behaves, but it was explaining how a bat is.  We can explain how a cell functions, but asking what it is like to be a cell is only useful as a thought experiment for humans to learn more about cells.  I am relatively confident that there is no such thing as a “cellular experience” in the subjective sense.

However, this problem goes much deeper than just our inability to understand what it is like to actually be another animal (or an individual cell).  We also have an inability to understand another human’s subjective experiences.  Michael Stevens recently used colour to explain this philosophical conundrum:

“Colour does not exist in the outside world, beyond us, like gravity or protons do. Instead, colour is created inside our heads. Our brains convert a certain portion of the electromagnetic spectrum to colour. I can measure the wavelength of radiation, but I can’t measure or observe the experience of a colour inside your mind. So how do I know that when you and me look at a strawberry, and in my brain this perception occurs which I call “red” a perception like this doesn’t occur [‘not red’], which you have of course learned to call red, we both call it red, we communicate effectively, and walk away, never knowing just how different our internal experiences actually were.”

— Michael Stevens

This is not just an issue for colour.  This is really an issue for all subjective experience. Philosopher Joseph Levine called the difficulty that physicalist theories of mind have in explaining the way things feel when they are experienced (qualia) the “explanatory gap.”  Explaining subjective experience and qualia is still known today as “the hard problem.”  We have no way to know whether my red is the same as your red.

I have given this some further thought over the last few days and I couldn’t help but think about “the hard problem” from an evolutionary perspective.  As I stated above, I agree with Nagel that we may be forever impeded from knowing what it is like to be a bat.  This is because the evolutionary gap between humans and other animals is immense and we don’t know whether consciousness itself has evolved in different ways.  However, with human experience, can we not be relatively confident that our subjective consciousness is relatively similar due to shared ancestry?  We are incredible similar genetically after all.  This may be another reductive attempt to understand a subjective phenomenon, but it seems plausible to me that my red is the same (or similar) to most other humans perception of red simply because, give or take a few cone and rod cells, a human eye is a human eye.

Of course, I am not a philosopher, and I don’t know whether this has been considered before, but it may be useful.

You can find Cadell Last and his evolutionary thoughts on Twitter.

Also posted via Svbtle:


Church, G. & Regis, E.  2012.  Regenesis: How Synthetic Biology Will Reinvent Nature And Ourselves.  New York: Basic Books.

Nagel, T.  1974.  What Is It Like to Be a Bat?  Philosophical Review, 83: 435-450.

Fraud Alert

Science has always had to deal with frauds, and perhaps human evolutionary science more than any other. The biggest of such hoaxes in human evolutionary science was the infamous Piltdown Man case. Piltdown Man consisted of a lower jawbone of an orangutan and the skull of a modern human (pictured above). It was deliberately buried in Sussex, England and was forged by an unknown individual in the early 20th century. For nearly half a century paleoanthropologists debated the validity of the skull and jawbone. And before being revealed as a hoax in 1953, scientists debated whether Piltdown Man represented the common ancestor of all modern humans. This obviously had enormous implications, and was used by many early 20th century scientists to justify racism against non-Europeans.

Since then the science investigating our origins has encountered many more frauds, most of them identifiable, but no one quite as deceptive and troubling as Dr. Melba Ketchum. She is a veterinarian and the founder of DNA Diagnostics. However, the only reason she is being discussed within the scientific community is because of her ongoing claim that she has sequenced three nuclear genomes of a Sasquatch.

For those of you who don’t know, the Sasquatch is a mythical animal that 16% of Americans believe to be a giant ape-like creature roaming the Pacific Northwest. Although there is absolutely no evidence that the Sasquatch exists, the myth persists. Ketchum, for a reason unknown to me, is trying to confuse the uninformed and discredit evolutionary anthropology by claiming it exists.

Of course, scientists in evolutionary anthropology have found surprising ancient hominids before. One of the most shocking was the discovery of Homo floresiensis (Brown et al., 2004), a small hominin most likely related to Homo erectus, that lived on an isolated island in contemporary Indonesia until between 13,000-17,000 years ago. The discovery of Homo floresiensis has certainly forced scientists to reconstruct the phylogenetic history of our species and the evolution of the genus Homo in Asia. However, the scientists that discovered Homo floresiensis were transparent with their methods and submitted their results to peer-reviewed journals so that the rest of the scientific community could evaluate their claims. Since their discovery other scientists have been given access to Homo floresiensis remains and other teams of paleoanthropologists have worked at the Liang Bua cave site where the remains were found to conduct further research by testing hypotheses. This process, the scientific process, allows real factual knowledge to be produced and considered by the world as a whole. This process prevents frauds from gaining cultural credibility and allows our species to continually improve our understanding of the universe. Consequently, our knowledge of Homo floresiensis morphology, ecology, behaviour, and phylogeny has accumulated over the past 9 years and our understanding of human evolution is much improved.

In contrast, the methods and data of Dr. Melba Ketchum’s “discovery” have hoax written all of them. She claims that her and her team of geneticists have been sequencing the DNA of the Sasquatch for the past five years, and that her results reveal that Sasquatch is extant (still living), and is a hominin hybrid that arose 15,000 years ago. Furthermore, she claims that the Sasquatch has novel nuclear DNA, but identical mitochondrial DNA to humans. The implications of her research, if true (which they aren’t), would force us to reconstruct the narrative of early human migration and expansion in North America. Her claims would indicate populations of the first human women in North America interbred with a large currently unknown extinct ape species producing a hybrid population of Sasquatch that has been hiding in North America for thousands of years.

Here is the official press release from Ketchum’s abstract in DeNovo Journal of Science (more on this journal later) from February 13, 2013:

“A team of eleven scientists with expertise in genetics, forensics, pathology, biochemistry, and biophysics has sequenced three whole nuclear genomes from a novel, contemporary species of hominin in North America. The study, “Novel North American Hominins, Next Generation Sequencing of Three Whole Genomes and Associated Studies,” which analyzed DNA from a total of 111 high-quality samples submitted from across the continent, appears in the inaugural issue of Denovo: Journal of Science ( on February 13.

The team, led by Dr. Melba S. Ketchum, DVM, of DNA Diagnostics in Nacogdoches, TX, sequenced the three whole nuclear genomes using the next-generation Illumina HiSeq 2000 platform at University of Texas, Southwestern from a tissue sample, a saliva sample, and a blood sample. The three genomes all attained Q30 quality scores above 88 on the Illumina platform, significantly higher than the platform average of 85, indicating highly-purified, single-source DNA with no contamination for each sample. The three Sasquatch genomes align well with one-another and show substantial homology to primate sequences.

In addition to the three nuclear genomes, Ketchum’s team also sequenced 20 whole and 10 partial mitochondrial genomes from the Sasquatch samples. In contrast to the nuDNA results, the Sasquatch mtDNA was fully modern Homo sapiens, indicating that the species is a hybrid cross between modern Homo sapiens in the maternal lineage and an unknown hominin male progenitor.”

Well that all seems legitimate doesn’t it? She worked with a lot of scientists, sequenced genomes from biological samples, and published her results in a scientific journal. So why am I calling her a fraud?

Science is concerned with facts and reality, so if her methods and data were sound, any scientific journal would jump at the opportunity to publish such an earth-shattering discovery. Unfortunately for Ketchum, no scientific journals are actually biting. DeNovo Journal of Science is a journal that mysteriously just came into existence. There is currently one edition of DeNovo with one scientific study (Ketchum’s “Sasquatch study”). Apparently Ketchum acquired the rights to this journal, but no one really knows how, and no one knows who peer reviewed the paper. Dr. Sharon Hill has called Ketchum out on her bullshit on Doubtful News and claims: “It looks suspicious. This is not how science works.”

The reason Ketchum couldn’t get through an actual peer review process in any scientific journal was because no one knows how or who collected the samples of ‘Sasquatch tissue, blood, and saliva.’ And there is no genetic database of Sasquatch DNA with which to compare and confirm the fact that those samples were from a Sasquatch. Furthermore, there is absolutely no evidence of a large ape from anytime in the natural history of North America.

To make matters even more ridiculous, Ketchum issued a statement to the United States government to recognize Sasquatch as:

“An indigenous people and immediately protect their human and Constitutional rights against those who would see in their physical and cultural differences a ‘license’ to hunt, trap, or kill them.”

She also claims:

“[We] have at our disposal, high-def footage, that will not be released until which time the publication finished, high-def video of the Sasquatch. It’s quite remarkable.”

If such footage actually existed, it is hard to figure out why she wouldn’t release it now, since it would potentially erase credibility issues regarding the collection of the samples she claims to have analyzed. Ketchum’s behaviour throughout this whole process has to make me wonder if she is psychologically stable. And if she is, that brings me to my biggest question: Why? Why is she doing this?

Her methods and data are so clearly fraudulent. Any educated individual would realize that something so methodologically flawed would not trick a 21st century scientific community. She is an actual geneticist, and as a result has nothing to gain from this and everything to lose. This whole debacle will only result in her marginalizing and discrediting herself. Why is she doing this? The only possibilities I can think would be to gain some measure of fame within fringe Sasquatch-believer groups. Perhaps as a result of that fame and notoriety she could make money from people coming to her with random animal samples that they want tested?

I’m not sure. Either way she is bad for science. And in my opinion, some science and most general news sources are treating this case fairly neutrally. I think that is bad for science as well. The science is either fraudulent or it isn’t. In the case of Ketchum, she is either trying to create a Piltdown Man for the 21st century, or she is psychologically imbalanced.

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Also posted via Svtble:


Brown, et al. 2004.  A new small-bodied hominin from the Late
Pleistocene of Flores, Indonesia. Nature, 431: 1055-1061.

Finding A Home

When I started my undergrad I knew I was interested in human evolution.  This interest developed into a fascination with our closest relatives.  I wanted to understand where we came from and studying the animal that we last shared a common ancestor with seemed like a good place to direct my focus.  As a result, I spent the summers of 2010 and 2011 in the Southwest province of Cameroon, collecting ecological data on chimpanzees and gorillas.  I have only rarely gone into detail about these trips onThe Ratchet but they were transformational experiences for my career as an evolutionary anthropologist.  And finally, three years after my first trip to Cameroon, Folia Primatologica published my first official academic paper based on my research findings from those trips (e.g., Last & Muh, 2013).  It is all very exciting, but the most rewarding aspect of this publication is that I believe it tells us a little bit about both our closest relatives and human evolution.

Conservation efforts are integral to the survival of all chimpanzee populations, however the population situation in Cameroon is probably worse than average.  This is because Cameroon has become an international hub for chimpanzee trafficking, and because there are no long-term field sites studying chimpanzees (Ghobrial et al., 2010).  As a result, we have very little data on the demographics, habitat, and health of these populations.  All populations are also unhabituated, meaning that they are deathly afraid of humans, and consequently it is impossible to study their behaviour.


As you might have guessed, that made it very difficult to collect data.  I couldn’t study chimpanzee behaviour in Cameroon, but I could study what they leave behind: nests and tools.  What I found is quite straightforward: chimpanzees in human-dominated landscapes prefer to nest arboreally (in trees), whereas chimpanzees in isolated-landscapes sleep both arboreally and terrestrially.  These findings may seem intuitive, but they offer conservationists in Cameroon an easy way to detect whether chimpanzee populations are under human threat.  In the future, conservationists should be able to tell whether a previously unknown chimpanzee population is feeling external anthropogenic pressure just by detecting the variability in nesting patterns.  Understanding this variability may also be a promising way to test for successful conservation initiatives designed to reduce human-chimpanzee conflict in rural areas.  Of course, future research is necessary to determine whether this is a general rule among this subspecies of chimpanzee, or whether more complex patterns emerge when other variables are controlled.

These findings also offer some clues regarding our own evolution.  Humans are well adapted to terrestrial living, but our closest relatives are not.  Chimpanzees knuckle-walk and are primarily adapted to an arboreal lifestyle.  We also know that our distant ancestors were likely arboreal knuckle-walkers (Kivell & Schmitt, 2009).    Anatomical evidence suggests that our ancestor’s had adjusted to a partially terrestrial existence by 4 million years ago (Lovejoy, et al., 2009), and possibly earlier (Pillbeam & Young, 2004).

Why?  When?  How?

Several hypotheses have been proposed but there is no universal consensus.  In all likelihood there were several environmental pressures.  However, my data suggests that predation may have played a pivotal role in the evolution of terrestrial existence.  Since the key variable for chimpanzee terrestrial night nesting was the presence/absence of a formidable predator (i.e., us), it is plausible to suggest that arboreal night nesting confers some important protection from predation.  In areas where there were little to no predation pressures, chimpanzee sleeping site selection was far more relaxed and variable.  The advantages to nesting terrestrially may not be obvious in a rainforest, however nesting terrestrially does have the added benefit of increasing niche flexibility.

In our distant past, the threat of aggressive social predators would have been high, and competition for food would have been fierce (Vermeij, 2010).  Arboreal night nesting would have been the best strategy to avoid predation at night.  This has been confirmed by primatological studies that indicate primate sleep site selection is determined by decreasing the likelihood of attack from a nocturnal predator (Anderson, 2000).

However, during one transition to terrestriality, our ancestors started nesting on the ground.  Bipedality itself likely evolved before this in order to save energy and carry food resources/infants across savanna landscapes (Ishida, 2006).  During this transition our ancestors were likely a terrestrial/arboreal hybrid, utilizing bipedality for travel and nesting arboreally at night.  So at some point the benefits of sleeping terrestrially outweighed the risks of predation.  It is unclear at the moment when exactly this transition occurred, but it is plausible to assume it had happened before the emergence of Homo erectus, and possibly even before the emergence of the genus Homo.  If this is the case, fire and tool construction may have played an important role in the permanent transition to the ground.  Future research will be needed to answer those questions.

As I stated above, as an undergrad I knew I wanted to better understand our origins.  I feel as though my first real research trip accomplished this.  It is by no means revolutionary, but it adds to the discussion.  Our closest relatives have a hard time nesting at night, largely because of human pressure.  Ironically, these pressures may be similar to those encountered by our ancestors throughout our evolution.  Finding a home has always been problematic.  In the future, I hope I can continue to utilize primatological research (and The Ratchet!) to inform our understanding of our species origins.

If you want to read the article – link here.

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Anderson, R.  2000.  Sleep-related behavioural adaptations in free-ranging anthropoid primates. Sleep Medicine Reviews, 4: 355-373.

Kivell, T.L. & Schmitt, D.  2009.  Independent evolution of knuckle-walking in African apes shows that humans did not evolve from a knuckle-walking ancestor.  Proceedings of the National Academy of Sciences of the United States of America, 106: 14241-14246.

Ghobrial, L., et al.  2010.  Tracing the origins of rescued chimpanzees reveals widespread chimpanzee hunting in Cameroon.  BMC Ecology, 10, doi: 10.1186/1472-6785-10-2.

Last, C. & Muh, B.  2013.  Effects of human presence of chimpanzee nest location in the Lebialem-Mone Forest Landscape, Southwest Region, Cameroon.  Folia Primatologica, 84: 51-63.

Lovejoy, O.C. et al.  2009.  The pelvis and femur of Ardipithecus ramidus: The emergence of upright walking.  Science, 326: 71e1-71e6.

Pillbeam, D. & Young, N.  2004.  Hominoid evolution: synthesizing disparate data.  Comptes Rendus Palevol, 3: 305-321.

Vermeij, G.J.  2010.  The Evolutionary World: How Adaptation Explains Everything from Seashells to Civilization.  New York: St. Martin’s Press.