BBC News has reported on two studies of chimpanzees and orangutans that indicate traits of sociability and capacities of memory not previously associated with apes. It may be said that these two members of the ape clan have the ability to party and remember what happened the next day.
The findings as to chimp and orangutan memory, by a team of scientists led by Gemma Martin-Ordas of Aarhus University in Denmark, were published in the journal Current Biology.
Chimpanzees have been observed modifying sticks, rocks and bones as tools to gather ants, nuts and honey. Orangutans also use sticks to pick up termites. (BBS News)
West Africa chimpanzees near Kédougou, Senegal engage in the practice of breaking off limbs from trees, stripping off the bark and sharpening one end with their teeth. They use the weapons to hunt galagos sleeping in the hollows of trees. Galagos are small, nocturnal primates also known as “bush babies” because of the sounds of their cries. (Wikipedia)
An orangutan on the island of Kaja in Borneo was photographed utilizing a spear to fish. He had seen humans doing this on the Gohong River. The photo was published by the UK MailOnline, the photo and text taken from a book entitled Thinkers of the Jungle: The Orangutan Report. The orangutan was also seen to employ a spear to pry open fruit.
The researchers in the Denmark group devised a memory test in which chimps and orangutans were presented with boxes of tools placed in separate rooms. They had to distinguish the useful tools from the useless ones in order to merit a reward. Not only did they learn to choose the useful tools, but 90% of them remembered the difference three years later.
Sounds and smells can inspire recollections in humans. But the same process might happen in apes, as determined by Dr. Martin-Ordas and her group.
In her web site roots & shoots, Jane Goodall argues that chimps are capable of intellectual thought,decision-making, problem-solving and reasoning. They have the cognitive skills to comprehendabstract ideas and symbolic representation as well as to generalize from specific experience.
In addition, experiments have shown that chimps possess a level of analogical reasoning. (deepdyve) Analogical reasoning is a method of processing information by comparing similarities between a previously understood concept and a novel one. (wiseGEEK)
By way of illustration, a child can look at a model of a room and then go into the full-scale room and relate to the objects there that she had seen in the model. (John Medina, Brain Rules) While it has been presumed that great apes have only a rudimentary ability to engage in analogical reasoning compared to human children, a Ph.D. candidate at the University of Heidelberg conducted an experiment in which an ape was presented with two sets of three cups each. One of the cups contained a reward. The subject was to choose the cup in the second array, concealing the reward, that was in the same relative position as the one in the first array. The ape seemed to encode the information about which of the three covered the reward in each array by the use of nearby landmarks rather than by a comparison of the two arrays. The results of the experiments further imply that children employ the same “mapping strategy” as apes in this regard. (Heidok)
The Chimpanzee-Human Last Common Ancestor (CHLCA) may have existed 5 and 7 million years ago. (Wikipedia) It is like that the last common human-orangutan ancestor migrated between Africa, Europe, and Asia 12 million to 13 million years ago. (Science Daily)
How it is believed to work is that chimps and men are part of the superfamily Hominoidea. They are both members of the subfamily Homininae, which also contains orangutans, gorillas and gibbons. The next level that humans and chimps share is the Hominini tribe. About four to six million years ago, humans split from the Hominini tribe. Humans became the Hominina subtribe, and chimps formed the Panina subtribe. (PaleontologyWiki) It’s just that simple.
The accepted doctrine is that chimps are the closest living relatives to humans, because their DNA is 99% identical.
But research conducted in 2009 indicates that DNA analysis may not be the best way to determine familial relations. The study, published in the Journal of Biogeography, detailed an analysis of unique physical characteristics among humans and apes. The researchers concluded that humans shared 28 characteristics with orangutans, seven with gorillas and only three with chimpanzees. It may even be that humans and orangutans belong to a group separate from chimpanzees and gorillas.
In any event, the Denmark study intimates that if chimps and orangutans possess episodic memory, they may have had that facility before human beings were established as distinct from the ape group.
Chimps and orangutans have memory, but do they also know how to party?
BBC News previously recounted a study by researchers at the University of Edinburgh that compared humans, chimps and orangutans using five “dimensions” of personality. Questionnaires were sent to 230 people in the US, Canada, Australia and Japan who have studied chimps and orangutans at zoos and research centers. The participants were asked to describe chimps and orangutans by 40 to 50 personality items and then to rate each item on a one-to-seven scale.
It appears that no questionnaires were filled out by the apes.
The dangers of anthropomorphism and projection were minimized by statistical techniques to remove observational biases from the data used to create the personality dimensions.
The five dimensions of personality are: neuroticism, extroversion, openness to experience, agreeableness and conscientiousness.
Chimps displayed all five of them. Orangutans had three out of five: neuroticism, extraversion and agreeableness.
Therefore, chimps, orangutans and humans are decidedly neurotic, extroverted and affable. We must concluded that they all know how to party, can remember what happened the night (or three years) before, and can feel guilt and shame about the experience.
By: Tom Ukinski