May 15, 2008
Links 14 (Primates)
Sorry for the silence. It's been a strange week. I've also been busy with work-related web stuff which means I wanted to get away from the computer, not spend more time in front of it. This may continue for a while.
Anyway, let's get back to emptying my overflowing bookmarks list. Today I have a bunch of primate links. I had lots more but I narrowed them down to ten, which are hopefully the most interesting or attention-grabbing. I also tried to choose links that weren't too lengthy or scholarly (read: journal articles that would bore most readers of this blog), so most of the links are to articles from New Scientist. New Scientist often veers into oversimplification and tabloid science (see 'A Plea to Save New Scientist'), but longtime readers know I routinely link to their articles because they're usually good for casual readers but always cite primary sources if something piques your interest. Without further ado:
1. Girrrrl power - "Females were persistently attacked by adult males, during this time. But, between October and December 2003, he noticed the females were starting to organise themselves into retaliation coalitions." - This is quite an interesting observation because it's not what one would expect based on conventional wisdom about chimpanzees. Bonobo females band together to combat male aggression, but as far as I know, this is the first observation of the behavior among chimpanzees, at least in East Africa. It has long been hypothesized that ecology is largely responsible for this interspecific difference. (Briefly, different food sources allow for different foraging patterns, which keep females from being alone and allow for more female bonding, etc.) But perhaps ecological and demographic conditions affect intraspecific and even intercommunity differences. I would love to see more research done on this. (And every other aspect of ape behavior, before they're gone in the wild. Our closest relatives can tell us much about human behavior, past and present.)
If you have access to the International Journal of Primatology you can read the journal article. Also look at this research brief.
2. New monkey species is already endangered (see also).
It's a new species of uakari. (The most well-known, or at least the most visually striking, uakari is the bald-headed uakari.)
3. 'Altruistic' chimps act for the benefit of others - The journal article is available from PLoS. The evolutionary origins of so-called "altruistic" behaviors are fascinating (and contentious). Studying the behavior of living species isn't the only way of approaching the question, but it is a very useful one. Chimpanzee behavior is of interest for human altruism simply because we are so closely related.
Primate characteristics satisfy many prerequisites for reciprocal altruism (long lifespans, large brains, long-term social relationships, etc.). Still, it may be that reciprocity explains only a small slice (if any) of altruistic behavior, even among big-brained apes. I would highlight de Waal's quote in the article:
"Animals don't know much about genetic kinship or future return favours," de Waal says, arguing that altruism could still be a self-serving trait, helping to win the "altruist" a good reputation and higher status.
4. Bonobos join forces to outdo chimps
5. Killings of mountain gorillas in Congo prompt U.N. probe - I may have mentioned this story last year, but I don't think I linked to these disturbing, heartbreaking photos.
Such a shame... this species, like so many primate species, is doomed to imminent extinction.
6. Chimps keep busy to control their urges - "In the experiment, the primates distracted themselves by playing with toys in order to avoid giving in to the temptation of eating instantly available candy so they could obtain even more treats at a later time."
7. Menopause sets humans apart from chimps - and, really, from all our ape cousins. It's an obvious, glaring difference that begs for explanation. There are several hypotheses and much intriguing research. One hypothesis for the adaptiveness of human menopuase is briefly discussed in one of article's links: Caring grandmas explain evolutionary role of menopause.
8. 5-year-old chimp beats college kids in computer game - "Japanese researchers pitted young chimps against human adults in two tests of short-term memory, and overall, the chimps won."
Even with six months of training, the college students couldn't catch up to the chimps. Tetsuro Matsuzawa's explanation? "He thinks two factors gave his chimps the edge. For one thing, he believes human ancestors gave up much of this skill over evolutionary time to make room in the brain for gaining language abilities." Maybe.
9. So college students are worse than chimps at short-term memory games. What about arithmetic? Turns out they're at about the same level as macaques: Monkeys perform arithmetic as well as college students.
10. New World monkeys are also clever. Here's an article about an interesting study on capuchin monkeys: Monkeys learn to do arithmetic for peanuts
I tried to hold the list to ten, but I just noticed this link in my bookmarks list and I have to share:
11. Did we learn to walk in the trees? (and more comment from the author's blog)
Conventional wisdom holds that apes developed bipedal locomotion after (or, more accurately, as) they descended from the trees. (Why and exactly how remain hotly debated.) A year or two ago, I started to very seriously consider a different possibility - that the bipedal locomotion of hominids actually started in the trees. Although heretical, the idea is attractive for a variety of reasons. (I don't have time to expound, but suffice it to say I think it matches some evidence in ways other hypotheses do not). Perhaps the knuckle-walking of gorillas and chimpanzees is derived and bipedal locomotion is ancestral (not, as traditionally thought, the other way 'round). You will need a subscription to read the full article from the first link, but I have a copy of the entire article. E-mail me if you're interested. I can also point you to some more reading on the topic.
15 May 22:02 | Link | Category: Human/Primate Evolution & Behavior, Link Dump '08, Science