Could Nim do this?
Back in the 1970s, a chimpanzee named Nim Chimpsky took part in a Columbia University research study called "Project Nim."
Project Nim was led by Herbert Terrace, a psychologist at Columbia who was attempting to find out if a chimpanzee could learn to communicate using American Sign Language.
"Everyone knows that words are learned one at a time," but something happens when children begin to combine words and create true language, Terrace says.
Chimpanzees aren’t endangered because they’re on TV
This week in Science - The inappropriate use and protrayal of Chimpanzees:
In 2005, a survey (see the table, left side) was conducted at the Regenstein Center for African Apes (RCAA) at the Lincoln Park Zoo (Chicago, IL). (...) The final question of the survey asked respondents to select which of three great ape species (chimpanzees, gorillas, and orangutans) were considered endangered in the wild. Of those choices, 95% of respondents thought gorillas were endangered, 91% thought orangutans were endangered, but only 66% believed chimpanzees to be endangered. (...) Respondents were informed that, in fact, all three great apes were classified as endangered and then asked for a reason why they thought a particular ape was not considered in this category. No prompting with answers was provided, and all responses were recorded by the interviewer. Of the 250 respondents who were willing to provide explanations for their choice, the most common reason for the category chosen (35%) was that chimpanzees were commonly seen on television, advertisements, and movies and, therefore, must not be in jeopardy.
Dear Zoo Visitor…
Dear Zoo Visitor:
Sorry to hear about your disappointment during your visit, but, yes, “sexual” behavior is normal for bonobos in the wild, including juveniles. In fact, most behaviors, obviously all those involving juveniles, that involve two or more bonobos in “sexual” activity are not really sexual in the sense of procreation, rather they are social. “Homosexual” behavior in bonobos like what you may have witnessed is not analogous to that seen in humans, regarding either intentions or anatomy. It appears that much of the sexual activity is a form of bonding, appeasement and displacement that replaces some of the grooming and aggression seen in other species.
Do chimps have culture? a phylogenetic study
Do chimps have culture? a phylogenetic study
Over the last few years, the evidence has been accumulating that different populations of chimpanzees have different cultures. Field studies of chimp behaviors (e.g. Whiten et al 1999 (PDF)) have shown a wide range of behavioral variation across Africa.
For example, chimps at one site, Bossou, use stone hammers and anvils to open nuts, whilst at another site, the chimps use both wooden and stone hammers on anvils made of stone and root. More examples, from White et al, show some of the variation in types of behavior and how they differ across research sites:
| sites | |||||||
|---|---|---|---|---|---|---|---|
| Behavior | Bossou, Guinea | Taı̈ Forest, Ivory Coast | Gombe, Tanzania | Mahale (M-Group), Tanzania | Mahale (K-Group), Tanzania | Kibale Forest, Uganda | Budongo Forest, Uganda |
| Investigatory probe (probe and sniff) | Habitual | Customary | Customary | Habitual | Habitual | Present | Absent |
| Drag branch (drag large branch in display) | Habitual | Customary | Customary | Customary | Customary | Habitual | Habitual |
| Leaf-sponge (leaf mass used as sponge) | Customary | Customary | Customary | Present | Absent | Customary | Customary |
| Branch-clasp (clasp branch above, groom) | Habitual | Customary | Customary | Customary | Customary | Customary | Customary |
| Branch-shake (to attract attention, court) | Customary | Customary | Customary | Customary | Customary | Habitual | Customary |
| Buttress-beat (drum on buttress of tree) | Customary | Customary | Customary | Customary | Customary | Customary | Customary |
| Rain dance (slow display at start of rain) | Absent | Habitual | Customary | Customary | Customary | Customary | Habitual |
It has been suggested that this type of variation is representative of cultural traditions, and hints at a new field of study: cultural panthropology. However, not everyone is convinced that this is evidence of chimpanzee culture. This could just be the outcome of genetic differences between the populations.
To test this, Lycett et al, forthcoming in P.N.A.S., take the Whiten et al data, and analyse it within a phylogenetic framework (parsimony). This gave them a tree showing the cultural relatedness of these groups. If this behavioral variation is due to genetics, then this tree should conform to the groupings found in previous genetic analyses.
This is not the case - the behavioral data does not mirror the genetic data. Lycett et al conclude that:
These findings are inconsistent with the hypothesis that patterns of behavioral differences at the population level are genetically determined. Instead, they are in line with a growing number of studies involving captive groups (...) and wild populations (...) that suggest many chimpanzee behaviors are socially learned and can be considered cultural.
Reference:
Lycett et al: Phylogenetic analyses of behavior support existence of culture among wild chimpanzees
25 Most Endangered Primates
National Geographic & the world's 25 most endangered primates.
Science special issue on social cognition
This week's Science is a special issue on social cognition, and has a bundle of fun little articles (all of which are subscription only), starting with a review of "Social Components of Fitness in Primate Groups" by Joan Silk:
There is much interest in the evolutionary forces that favored the evolution of large brains in the primate order. The social brain hypothesis posits that selection has favored larger brains and more complex cognitive capacities as a means to cope with the challenges of social life. The hypothesis is supported by evidence that shows that group size is linked to various measures of brain size. But it has not been clear how cognitive complexity confers fitness advantages on individuals. Research in the field and laboratory shows that sophisticated social cognition underlies social behavior in primate groups. Moreover, a growing body of evidence suggests that the quality of social relationships has measurable fitness consequences for individuals.
This is followed by Herrmann et al's "Humans Have Evolved Specialized Skills of Social Cognition: The Cultural Intelligence Hypothesis", where they test the idea that one of the reasons that humans are smart is because we've developed a special set of cognitive skills for handling social tasks:
Humans have many cognitive skills not possessed by their nearest primate relatives. The cultural intelligence hypothesis argues that this is mainly due to a species-specific set of social-cognitive skills, emerging early in ontogeny, for participating and exchanging knowledge in cultural groups. We tested this hypothesis by giving a comprehensive battery of cognitive tests to large numbers of two of humans' closest primate relatives, chimpanzees and orangutans, as well as to 2.5-year-old human children before literacy and schooling. Supporting the cultural intelligence hypothesis and contradicting the hypothesis that humans simply have more "general intelligence," we found that the children and chimpanzees had very similar cognitive skills for dealing with the physical world but that the children had more sophisticated cognitive skills than either of the ape species for dealing with the social world.
Next up is another paper by Robin Dunbar and Susanne Shultz on Evolution in the Social Brain (henry covered their previous paper too):
The evolution of unusually large brains in some groups of animals, notably primates, has long been a puzzle. Although early explanations tended to emphasize the brain's role in sensory or technical competence (foraging skills, innovations, and way-finding), the balance of evidence now clearly favors the suggestion that it was the computational demands of living in large, complex societies that selected for large brains. However, recent analyses suggest that it may have been the particular demands of the more intense forms of pairbonding that was the critical factor that triggered this evolutionary development. This may explain why primate sociality seems to be so different from that found in most other birds and mammals: Primate sociality is based on bonded relationships of a kind that are found only in pairbonds in other taxa.
Heading right down the cognitive path is Prospection: Experiencing the Future by Gilbert and Wilson, who review some recent work on "mental time travel":
All animals can predict the hedonic consequences of events they've experienced before. But humans can predict the hedonic consequences of events they've never experienced by simulating those events in their minds. Scientists are beginning to understand how the brain simulates future events, how it uses those simulations to predict an event's hedonic consequences, and why these predictions so often go awry.
David Premack on the differences between human and animal cognition
David Premack reviews the differences between animal and human cognition in "Human and animal cognition: Continuity and discontinuity" (doi). Abstract only:
Microscopic study of the human brain has revealed neural structures, enhanced wiring, and forms of connectivity among nerve cells not found in any animal, challenging the view that the human brain is simply an enlarged chimpanzee brain. On the other hand, cognitive studies have found animals to have abilities once thought unique to the human. This suggests a disparity between brain and mind. The suggestion is misleading. Cognitive research has not kept pace with neural research.
Neural findings are based on microscopic study of the brain and are primarily cellular. Because cognition cannot be studied microscopically, we need to refine the study of cognition by using a different approach. In examining claims of similarity between animals and humans, one must ask: What are the dissimilarities? This approach prevents confusing similarity with equivalence. We follow this approach in examining eight cognitive cases—teaching, short-term memory, causal reasoning, planning, deception, transitive inference, theory of mind, and language—and find, in all cases, that similarities between animal and human abilities are small, dissimilarities large. There is no disparity between brain and mind.
Update: That would be David Premack not Daniel Premack. My apologies!