A primate's response to death

By: Thomas Schmitt Attorney on June 28, 2019 / comment : 0 Anthropology, Human Evolution, Psychology, Wildlife

According to archaeological records, early humans began doing what no other primate had done before; intentionally covering their dead with earth. From these simple beginnings, we developed our funerary practices making humanity's attitude toward death a defining part of our species.

'Monkey in Front of Skeleton' by Gabriel Cornelius Ritter von Max, c.1900 [Credit: Kyoto University]

And as our understanding of other living creatures grows, we realize that humans are not the only ones whose behaviour changes in the presence of death. Known today as 'Comparative Thanatology', researchers extensively study the cognitive, psychological, and physiological aspects of death among non-human animals.

In the first in-depth review on comparative thanatology in primates, André Gonçalves of Kyoto University's Primate Research Institute and Susana Carvalho of Oxford University analyzed over 200 years of documentation on non-human primates interacting with their dead. Bringing together the diverse field of comparative thanatology, the findings include an evolutionary timeline of mortuary practices, and covers fields from archaeology to psychology.

Observations and anecdotal evidence both in the wild and in captivity go as far back as the 19th century. Gonçalves reports that while certain responses differ between primate species, common behaviours are observed: primates defended dead companions against threats, carried their dead, and even exhibited emotional responses that can be described as 'grief'.

"Although these earlier anecdotes are anthropomorphic, the behavioural patterns are consistent to what is observed today," he says.

The team compiled and reviewed an extensive record of 240 reports to fulfill three primary goals: documenting history, collecting and interpreting the current data, and developing an evolutionary frame-work of death responses in primates.

"Non-human primates exhibit all sorts of behaviour related to death, one of the most prevalent are mothers carrying their dead offspring. Many factors contribute to this behaviour, but we find that they do it because they have the ability to grasp objects," continues Gonçalves. "Interestingly, primates such as lemurs or tamarins do not engage in this behaviour despite continued attempts. We find that this is because they lack that same grasping ability."

When an adult member dies, different sets of patterns are observed, such as holding vigils, and guarding or visiting the body. The team reports that these interactions likely come as a by-product of attachment relationships. They also infer that this allows the primates to learn vital information from the corpses, serving as a way to re-categorize the individual from living to dead -- an essential part of the grieving process -- and informing on potential shifts in the group's hierarchy.

Moreover, the team proposes that non-human primates are capable of an implicit awareness of death.

"It's not an all-or-nothing ability. Awareness of death includes things such as animate/inanimate distinction, or the sensory and contextual discrimination of living/dead," Gonçalves explains. "The concept of death is something we humans acquire between ages 3 to 10. We can infer that non-human primates have some aspects of death awareness but, thus far, only humans conceptualize it at a higher order."

While a few anecdotes suggest great apes may indeed have a concept of death like humans, Gonçalves and Carvalho state the need to formulate and test hypotheses in experimental settings.

The team intends to apply this comprehensive review to further their research in comparative thanatology, and hopes other scientists will explore different avenues of research to uncover our unique perspective of death.

The report was published in Biological Reviews.

Source: Kyoto University [June 28, 2019]

Re-inventing the hook: Orangutans spontaneously bend straight wires into hooks to fish for food

By: Thomas Schmitt Attorney on November 09, 2018 / comment : 0 Borneo, Endangered Species, Indonesia, Natural Heritage, Psychology, Sumatra, Wildlife

The bending of a hook into wire to fish for the handle of a basket is surprisingly challenging for young children under eight years of age. Now cognitive biologists and comparative psychologists from the University of Vienna, the University of St Andrews and the University of Veterinary Medicine Vienna around Isabelle Laumer and Alice Auersperg studied hook tool making for the first time in a non-human primate species - the orangutan. To the researchers' surprise the apes spontaneously manufactured hook tools out of straight wire within the very first trial and in a second task unbent curved wire to make a straight tool.

Wild male orangutan [Credit: © Graham L. Banes]

Human children are already proficient tool-users and tool-makers from an early age on. Nevertheless, when confronted with a task, which required them to innovate a hooked tool out of a straight piece of wire in order to retrieve a basket from the bottom of a vertical tube, the job proved more challenging for children than one might think: Three to five-year-old children rarely succeed and even at the age of seven less than half of them were able to solve the task. Only at the age of eight the majority of children was able to innovate a hook-tool. Interestingly children of all tested age classes succeeded when given demonstrations on how to bend a hook and use it. Thus, although young children apparently understand what kind of tool is required and are skilled enough to make a functional tool, there seems to be a cognitive obstacle in innovating one.

Cognitive biologists and comparative psychologists from the University of Vienna, the University of St Andrews and the University of Veterinary Medicine in Vienna around Isabelle Laumer now tested for the first time a primate species in the hook-bending task. "We confronted the orangutans with a vertical tube containing a reward basket with a handle and a straight piece of wire. In a second task with a horizontal tube containing a reward at its centre and a piece of wire that was bent at 90°", explains Isabelle Laumer who conducted the study at the Zoo Leipzig in Germany. "Retrieving the reward from the vertical tube thus required the orangutans to bent a hook into the wire to fish the basket out of the tube. The horizontal tube in turn required the apes to unbent the bent piece of wire in order to make it long enough to push the food out of the tube."

Male orangutan using a stick tool [Credit: © Alice Auersperg]

Several orangutans mastered the hook bending task and the unbending task. Two orangutans even solved both tasks within the first minutes of the very first trial. "The orangutans mostly bent the hooks directly with their teeth and mouth while keeping the rest of the tool straight. Thereafter they immediately inserted it in correct orientation, hooked the handle and pulled the basket up", she further explains.

Orangutans share 97% of their DNA with us and are among the most intelligent primates. They have human-like long-term memory, routinely use a variety of sophisticated tools in the wild and construct elaborate sleeping nests each night from foliage and branches. Today orangutans can only be found in the rainforests of Sumatra and Borneo. Like all four great ape species, orangutans are listed as critically endangered (IUCN, Red List). "Habitat loss due to extensive palm-oil production, illegal wildlife trade and poaching are the major threats. Palm oil is the most widely used vegetable oil in the world. As long as there is a demand for palm oil and consumers keep buying products that contain palm oil, the palm industry thrives. According to a 2007 survey by the United Nations Environment Program (UNEP) orangutans will be extinct in the wild within two decades if current deforestation trends continue", says Isabelle Laumer.

Orangutans in the wild [Credit: © Graham L. Banes]

"The hook-bending task has become a benchmark paradim to test tool innovation abilities in comparative psychology", says Alice Auersperg from the University of Veterinary Medicine in Vienna. "Considering the speed of their hook innovation, it seems that they actively invented a solution to this problem rather than applying routined behaviours."

"Finding this capacity in one of our closest relatives is astonishing. In human evolution hook tools appear relatively late. Fish hooks and harpoon-like, curved objects date back only approximately 16.000- 60.000 years. Although New Caledonian crows use hooks with regularity, there are a few observations of wild apes, such as chimpanzees and orangutans, that use previously detached branches to catch and retrieve out-of-reach branches for locomotion in the canopy. This branch-hauling tools might represents one of the earliest and simplest raking tools used and made by great apes and our ancestors", says Josep Call of the University of St Andrews.

So why struggle younger children with this task? "Follow-up studies showed that childrens difficulty with independently finding the solution cannot be explained by fixedness on unmodified tools, impulsivity nor by not being able to change the strategy. The hook bending task represents a complex problem, for which several unrewarded steps must be performed while keeping the final goal in mind", explains Isabelle Laumer. "Interestingly, complex problem solving has been associated to certain areas of the medial prefrontal cortex, which mature later in the child development. This explanation, besides children´s strong reliance on social learning might explain their success at a later age."

The study is published in Scientific Reports.

Source: University of Vienna [November 09, 2018]

Do lizards dream like us?

By: Thomas Schmitt Attorney on October 11, 2018 / comment : 0 Biology, Evolution, Psychology

Researchers from the Sleep Team at the Lyon Neuroscience Research Center (CNRS / INSERM / Claude Bernard Lyon 1 University / Université Jean Monnet), together with a colleague from the MECADEV research laboratory (CNRS / Muséum National d'Histoire Naturelle) have confirmed that lizards exhibit two sleep states, just like humans, other mammals, and birds. They corroborated the conclusions of a 2016 study on the bearded dragon (Pogona vitticeps) and conducted the same sleep investigation on another lizard, the Argentine tegu (Salvator merianae). Their findings, published in PLOS Biology, nevertheless point out differences between species, which raises new questions about the origin of sleep states.

In addition to replicating the 2016 bearded dragon experiment, researchers conducted a new investigation using another species of lizard, the Argentine tegu (Salvator merianae) [Credit: Paul-Antoine Libourel]

During sleep, the body carries out many vital activities: consolidation of knowledge acquired during the day, elimination of metabolic waste from the brain, hormone production, temperature regulation, and replenishment of energy stores. It would appear that this physiological phenomenon is shared by all members of the animal kingdom and has been preserved throughout evolution. But scientists long thought that only land mammals and birds experienced two separate sleep states: slow-wave sleep and REM, or paradoxical, sleep. The latter, associated with dreaming, is a complex phase during which the body exhibits behaviors in limbo between those of sleeping and waking hours.

A study whose findings were published by Science in 2016 focused on the bearded dragon (Pogona vitticeps) and demonstrated that this lizard also entered two distinct sleep states. It further hypothesized that such sleep states originated in a common ancestor of mammals and reptiles, 350 million years ago.

The team of researchers from the CNRS and Claude Bernard Lyon 1 University began by replicating the 2016 bearded dragon experiment. They then conducted a new investigation using another species of lizard, the Argentine tegu (Salvator merianae). Their data confirm both lizards go into two distinct sleep states bearing similarity to slow-wave and REM sleep, respectively.

But their analysis of behavioral, physiological, and cerebral parameters dug deeper and revealed differences not only between the sleep of the lizards and the sleep of both mammals and birds, but also between the two lizard species. Although human REM sleep is characterized by cerebral and ocular activity similar to that observed while awake, the corresponding state in both lizard species is associated with slower eye movements and, in the case of the tegu, cerebral activity very unlike that of waking hours.

These differences observed by the researchers paint a more complex picture of REM sleep in the animal kingdom and open new doors for investigations into the origin of our own sleep patterns and dreams . . . and those of lizards.

Source: CNRS [October 11, 2018]

Discovery of first genetic variants associated with meaning in life

By: Thomas Schmitt Attorney on October 03, 2018 / comment : 0 Anthropology, Genetics, Psychology, Society

For the first time, locations on the human genome have been identified that can explain differences in meaning in life between individuals. This is the result of research conducted in over 220,000 individuals by Professor Meike Bartels and PhD student Bart Baselmans from the Vrije Universiteit Amsterdam. The researchers identified two genetic variants for meaning in life and six genetic variants for happiness. The results were published this week in the scientific journal Scientific Reports.

Credit: Vox

The fact that genetic variants for a meaning in life have been found indicates that everyone is different and that differences between people in complex processes such as a meaning in life are in part due to biological differences. VU professor Meike Bartels: "We live in a society where everyone is expected to thrive, achieve the highest, and live a meaningful life. If we have a better idea of the causes of differences between people, we can use that information to help people who feel less happy or struggle with the meaning of life. We also find that there are environmental factors that are important for happiness, but not for meaning and vice versa. In the future we would like to identify which environmental factors are responsible for this discrepancy."

Individual differences

Previous research has shown that individual differences in happiness and well-being can partly be attributed to genetic differences between people. Furthermore, the first genetic variants for happiness were found a few years ago. Baselmans: "These results show that genetic differences between people not only play a role in differences in happiness, but also in differences for in meaning in life. By a meaning in life, we mean the search for meaning or purpose of life."

220 thousand DNA samples

All people who participated in the study are part of the UK Biobank and have donated a DNA sample and completed a questionnaire. Bartels: "We then tested which genetic variants in the DNA lead to differences in meaning in life." The genetic variants are mainly expressed in the central nervous system, showing the involvement of different brain areas.

Source: Vrije Universiteit Amsterdam [October 03, 2018]

Study finds a conserved role for serotonin in regulating behaviour in octopus, humans

By: Thomas Schmitt Attorney on September 20, 2018 / comment : 0 Biology, Evolution, Psychology

The mood-altering drug MDMA - which promotes positive, friendly social interactions in humans by inhibiting serotonin uptake in nerve cells - has a similar behavioral effect in an octopus species, scientists report today. This indicates that serotonin has been functioning as a regulator of social behavior for at least 500 million years, when the human and octopus lineages evolutionarily diverged.

By studying the genome of a kind of octopus not known for its friendliness toward its peers, then testing its behavioural reaction to a popular mood-altering drug called MDMA or 'ecstasy,' scientists say they have found preliminary evidence of an evolutionary link between the social behaviours of the sea creature and humans, species separated by 500 million years on the evolutionary tree [Credit: Tom Kleindinst]

The study, conducted by Gül Dölen, assistant professor of neuroscience at Johns Hopkins University School of Medicine and Eric Edsinger, research scientist at the Marine Biological Laboratory, is published this week in Current Biology.

Serotonin is an evolutionarily ancient chemical, with forms of it found across the animal kingdom and even in plants, where it regulates growth. In humans, where it transmits messages between nerve cells, serotonin is a well-known regulator of mood and is closely linked to some types of depression.

Edsinger, who was on the team that sequenced the first octopus genome in 2015 (Octopus bimaculoides) and Dölen took a close look at the genes involved with serotonin uptake in the octopus genome. They found that one important link in this process -- a transporter protein that vacuums serotonin up from the synapse (the communication junction between nerve cells), allowing the next round of serotonin release to be received as a discrete signal -- has regions that are nearly identical in human and in octopus. Some of these regions are also known to be involved in how the drug MDMA binds to brain cells and alters mood.

"The binding site for MDMA and serotonin in the ion transporter is 100 percent conserved between octopus and human. That is an extraordinary level of conservation. That means, pharmacologically, we could predict MDMA should work in octopus in the way it does in humans. It looks like it did," Edsinger says.

At Johns Hopkins, Dolen designed social behavior experiments with octopuses, testing their interactions with and without the drug. Octopus bimaculoides are known to be predominantly asocial creatures, preferring solitude and under the wrong conditions, killing and eating each other. Administration of MDMA, however, seemed to enhance prosocial behaviors.

"Octopuses aren't 100 percent asocial; they have some tolerance for each other," Edsinger says. "The drug probably amplified a low level of tolerance a bit."

The scientists caution that the results are preliminary and need to be replicated in further experiments. However, discovering that the gene sequence for this serotonin transporter is conserved in human and octopus - meaning their last common ancestor also had it - is significant, Edsinger says.

"If a gene sequence is conserved for 500 million years, it must be very important," he says. "A human is a massively complex system and if you just look within that system, it is hard to know what is relatively important. But if you compare it to the genomes of other animals, you can find the critical elements that evolution just hasn't been able to change over millions of years. From a pharmacological or medical standpoint, these are the elements--such as this serotonin transporter--that may be really important to make sure are functioning correctly."

Octopuses for the experiments were cultured at the Marine Biological Laboratory, which has a growing program to culture and develop cephalopods as genetic model organisms for biological and biomedical research.

Source: Johns Hopkins University School of Medicine [September 20, 2018]

Every person has a unique brain anatomy

By: Thomas Schmitt Attorney on July 10, 2018 / comment : 0 Anthropology, Human Evolution, Neuroscience, Psychology

Like with fingerprints, no two people have the same brain anatomy, a study by researchers of the University of Zurich has shown. This uniqueness is the result of a combination of genetic factors and individual life experiences.

Three brain scans (from the front, side and above) of two different brains (pictured on the left and on the right) belonging to twins. The furrows and ridges are different in each person [Credit: Lutz Jaencke, UZH]

The fingerprint is unique in every individual: As no two fingerprints are the same, they have become the go-to method of identity verification for police, immigration authorities and smartphone producers alike. But what about the central switchboard inside our heads? Is it possible to find out who a brain belongs to from certain anatomical features? This is the question posed by the group working with Lutz Jäncke, UZH professor of neuropsychology. In earlier studies, Jäncke had already been able to demonstrate that individual experiences and life circumstances influence the anatomy of the brain.

Experiences make their mark on the brain

Professional musicians, golfers or chess players, for example, have particular characteristics in the regions of the brain which they use the most for their skilled activity. However, events of shorter duration can also leave behind traces in the brain: If, for example, the right arm is kept still for two weeks, the thickness of the brain's cortex in the areas responsible for controlling the immobilized arm is reduced. "We suspected that those experiences having an effect on the brain interact with the genetic make-up so that over the course of years every person develops a completely individual brain anatomy," explains Jäncke.

Magnetic resonance imaging provides basis for calculations

To investigate their hypothesis, Jäncke and his research team examined the brains of nearly 200 healthy older people using magnetic resonance imaging three times over a period of two years. Over 450 brain anatomical features were assessed, including very general ones such as total volume of the brain, thickness of the cortex, and volumes of grey and white matter. For each of the 191 people, the researchers were able to identify an individual combination of specific brain anatomical characteristics, whereby the identification accuracy, even for the very general brain anatomical characteristics, was over 90 percent.

Combination of circumstances and genetics

"With our study we were able to confirm that the structure of people's brains is very individual," says Lutz Jäncke on the findings. "The combination of genetic and non-genetic influences clearly affects not only the functioning of the brain, but also its anatomy." The replacement of fingerprint sensors with MRI scans in the future is unlikely, however. MRIs are too expensive and time-consuming in comparison to the proven and simple method of taking fingerprints.

Progress in neuroscience

An important aspect of the study's findings for Jäncke is that they reflect the great developments made in the field in recent years: "Just 30 years ago we thought that the human brain had few or no individual characteristics. Personal identification through brain anatomical characteristics was unimaginable." In the meantime magnetic resonance imaging has got much better, as has the software used to evaluate digitalized brain scans - Jäncke says it is thanks to this progress that we now know better.

The findings are published in Scientific Reports.

Source: University of Zurich [July 10, 2018]

How our ancestors with autistic traits led a revolution in Ice Age art

By: Thomas Schmitt Attorney on May 14, 2018 / comment : 0 Anthropology, Early Humans, Europe, Psychology

The ability to focus on detail, a common trait among people with autism, allowed realism to flourish in Ice Age art, according to researchers at the University of York.

Detailed illustrations of lions painted in the Chauvet Cave [Credit: WikiCommons]

Around 30,000 years ago realistic art suddenly flourished in Europe. Extremely accurate depictions of bears, bison, horses and lions decorate the walls of Ice Age archaeological sites such as Chauvet Cave in southern France.

LSD

Why our ice age ancestors created exceptionally realistic art rather than the very simple or stylised art of earlier modern humans has long perplexed researchers.

Many have argued that psychotropic drugs were behind the detailed illustrations. The popular idea that drugs might make people better at art led to a number of ethically-dubious studies in the 60s where participants were given art materials and LSD.

The authors of the new study discount that theory, arguing instead that individuals with “detail focus”, a trait linked to autism, kicked off an artistic movement that led to the proliferation of realistic cave drawings across Europe.

Realism

Lead author of the paper, Dr Penny Spikins from the Department of Archaeology at the University of York, said: “Detail focus is what determines whether you can draw realistically; you need it in order to be a talented realistic artist. This trait is found very commonly in people with autism and rarely occurs in people without it.

“We looked at the evidence from studies attempting to identify a link between artistic talent and drug use, and found that drugs can only serve to disinhibit individuals with a pre-existing ability. The idea that people with a high degree of detail focus, many of which may have had autism, set a trend for extreme realism in ice age art is a more convincing explanation.”

Focus

The research adds to a growing body of evidence that people with autistic traits played an important role in human evolution.

Dr Spikins added:  “Individuals with this trait – both those who would be diagnosed with autism in the modern day and those that wouldn’t – likely played an important part in human evolution and survival as we colonised Europe.

“As well as contributing to early culture, people with the attention to detail needed to paint realistic art would also have had the focus to create complex tools from materials such as bone, rock and wood. These skills became increasingly important in enabling us to adapt to the harsh environments we encountered in Europe.”

The study is published in Open Archaeology.

Author: Shelley Hughes | Source: University of York [May 14, 2018]