[PHOTO] CN Tower, May 2012

Looking north from Queens Quay.

[BLOG] Some Friday links

• Centauri Dreams' Paul Gilster writes about long-lived artifacts, such as we or extraterrestrials might make to last for eons.


• Daniel Drezner writes about the ongoing question of what the United States should do in Mali. (Apparently it has to be asked.)


• The Dragon's Tales links to a study suggesting Titan has an active geology, with its carbon sand filling in craters.


• Far Outliers reports on the fine mechanics of racism in colonial Spanish America.


• The Global Sociology Blog notes the many ways in which the Arab Spring does not resemble protests against same-sex marriage in France.


• Marginal Revolution's Tyler Cowen speculates that cultural tourism will be more resilient than scenery-oriented tourism, on account of the limits of the digital world.


• Torontoist reports on the call by a group of Toronto physicians for more bike lanes sooner.


• Window on Eurasia notes that, after the 1969 Sino-Soviet clashes, landmarks on the Russian frontier with China were given new Russian names.

[LINK] "Chimps Might Have a Sense of Fair Play"

Michael Balter's ScienceNOW article highlights yet another commonality between humans and our nearest cousins, the chimpanzees. There's some question regarding the findings, described elsewhere in the article, but the conclusions seem plausible.

When economists and psychologists want to test fairness in humans, they turn to the Ultimatum Game. Typically, one subject, called the “proposer,” is given a sum of money to divide with a “responder.” If the responder accepts the proposer’s offer, both are rewarded. But if the responder rejects the offer, both get nothing. Although results vary, human proposers usually offer about 40 percent to 50 percent of the money, and responders reject offers that are under 20 percent — even though they will end up with nothing for doing so. Researchers interpret both behaviors as evidence for a basic sense of fairness.

In 2007, a team at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, tried the Ultimatum Game on chimps. In a simplified version of the game, the team gave the chimps set options about how to divvy up dishes of raisins, such as a 50-50 split or an 80-20 split. The proposer, in a cage next to that of the responder, made an offer by pulling a tray halfway toward the responder. The responder had to choose between pulling it the rest of the way so that both chimps could get the food or refusing to pull it at all, in which case both chimps got nothing. In contrast with humans, chimps rarely rejected offers of 20% of the food; they only rejected such tenders in experiments where the proposer had the additional choice of taking all of the food and leaving the responder with nothing. The team concluded that the responders would accept even the meanest split as long as they got something, suggesting that unlike humans, they were not offended by blatantly unfair offers.

Some researchers pounced on the study, however, suggesting that chimps couldn’t be expected to play fair given the conditions of their captivity, which had taught chimps that they had little control over how much they got to eat, or that they might not be able to understand the complicated tray-pulling apparatus.

To try to resolve the debate, a team led by primatologist Frans de Waal of Emory University in Atlanta has developed what it considers a more chimp-friendly version of the Ultimatum Game. In previous work, de Waal and his co-workers had established that chimps could be trained to exchange tokens for food. In the new study, published online this week in the Proceedings of the National Academy of Sciences, de Waal and his colleagues trained six chimps to recognize that such colored tokens, made of short pieces of plastic pipe, represented one of two ways of dividing six banana slices: an equal 3-3 split or an unequal 5-1 split (see video). The proposer chimp chose one of the tokens and then handed it through the wire mesh of its cage to a responder chimp, which had to give it to a human experimenter for both chimps to get the food. In essence, the tokens served as money that could be exchanged for the banana slices.

The chimps seemed to be playing fair. The percentage of equitable (3-3) offers ranged from 58% to 92%, much higher than in the Leipzig study which averaged about 25% for such 50-50 splits. However, as in the Leipzig study, the chimps never rejected “unfair” offers of 5-1 splits.

The team concluded that a sense of fairness arose sometime before the chimp and human lines split some 5 million to 7 million years ago, and that doing right by others has a long evolutionary history. “When we see this kind of behavior in humans, we call it fairness,” says the study’s lead author, psychologist Darby Proctor, now of Emory University, who adds that researchers shouldn’t “hesitate to call it fairness in chimps.”

[LINK] "Massacres Alter Social Structure of Africa’s Elephants"

Writing about elephants, ScienceNOW's Virginia Morell notes the sociological and demographic impacts of poaching on elephant populations. They're worrisome: leaving aside the actual decreases in the number of elephants, the selective killing of older elephants destabilizes the family groups that form the nuclei of elephant society. Even the baby boom that the researchers note is worrisome, indicating that the elephants' habitat can support far more elephants than actually live.

Poachers are slaughtering elephants across Africa at an unprecedented pace. But scientists tracking the animals’ carcasses—their faces and ivory hacked away—are seldom able to explain in detail what these deaths mean to the pachyderms’ populations and social structure. Now, a 14-year study of elephants in northern Kenya concludes that the adult behemoths are more likely to die at the hands of humans than from natural causes. At the same time, the elephants have responded to the heavy poaching with a baby boom, providing the researchers some hope for the jumbos’ survival.

[. . .]

In 1997, the scientists began a study on elephant behavior in two adjacent national reserves, Samburu and Buffalo Springs, which together measure 220 square kilometers. The parks’ elephants were accustomed to vehicles and easy to study; they had also recovered from heavy poaching in the 1970s. At the beginning of the study, illegal killing was rare. “We might lose one big male a year,” says George Wittemyer, a wildlife biologist at Colorado State University, Fort Collins, and the study’s lead author. “We thought the population was stable.” That changed in 2009 as poachers began shooting elephants en masse. The scientists then shifted their study to look at the effects the poaching was having on the elephants they knew.

At the study’s outset, the researchers focused on 934 individuals (509 females and 425 males). The team used a standard method for identifying each elephant, noting each animal’s unique markings on its ears and face, as well as the shape of its tusks. Then each week, from 1997 to 2011, the researchers drove along five, 20-kilometer routes inside the reserves and recorded the presence or absence of the study elephants. They considered any animals that they didn’t spot for more than 3 years to be dead. The scientists seldom found the carcasses of these animals, but they investigated any dead elephants reported by tourists or rangers that were inside the parks or within 10 kilometers of the reserves’ boundaries.

Although the elephant population was increasing when the study began, it began to decline as poachers targeted the animals. The older elephants, which have larger tusks, were especially hard hit. In 2000, there were 38 males over 30 years old in the study population. By 2011, their number had dropped to 12—and of those, seven had matured into this age class. Older females also suffered huge losses, with almost half of those 30 years old dying between 2006 and 2011. By 2011, 56% of the elephants that were found dead had been poached, the team reports online today in PLOS ONE.

The poaching spree has also altered the elephants’ social organization, the study shows. When the work began, males made up 42% of the population; by 2011, they had been cut down to only 32%. And 10 of the 50 elephant family groups that the scientists were studying were effectively wiped out. “They no longer have any breeding females,” Wittemyer explains. “And so, the family group has disappeared, leaving surviving juveniles on their own.” These youngsters may join other families, or, without a leader to guide them, try to survive in sibling groups typically led by the oldest sister.

“Some elephants died from a bad drought that hit the region between 2009 and 2010,” Wittemyer adds. “But at least half of these deaths were due to poaching.” The poaching took place outside the reserves on lands that are largely unpatrolled. In addition to the reserve, the elephants roam over a vast area of more than 3500 square kilometers.