A roundup of some of the week's science headlines:
Kind kids: Natural disasters can trigger generosity in older children, while younger kids become more selfish, according to a new study. Researchers from three institutions, including the University of Toronto, were in Sichuan, China, in May, 2008, when an earthquake killed 87,000. Already studying altruism in children, they tweaked their study. They asked two sets of children, aged six and nine, to choose 10 "favourite"stickers from an offering of 100. Then they told the children they could give the stickers to classmates who didn't have any by placing some in an envelope without anyone watching them. The older children were more generous and scored higher on a standard empathy test, the researchers said in a release. However, this effect seemed to vanish in follow-up evaluations done three years later – levels of altruism returned to what was seen before the disaster in both age groups. The study will be published in an upcoming issue of Psychological Science.
Whodunit? Humans were the sole culprits in driving Australia's Tasmanian tiger to extinction, challenging the belief that some sort of disease must have been a factor in the creature's disappearance. Though the Tasmanian tiger, or thylacine, vanished from mainland Australia about 2,000 years ago, the meat-eating marsupials lived on in Tasmania. After the arrival of settlers in 1803, the thylacine's numbers dwindled and the last known animal died in captivity in 1936. Using a mathematical model, researchers from the University of Adelaide simulated the effects of both a government-backed bounty hunting system and habitat loss, along with the impact of a reduced food supply, on the thylacine. They were able to create a scenario in which the Tasmanian tiger died out without the contribution of a mystery illness, the researchers said in a release. The study was published online in the Journal of Animal Ecology.
Death watch: A team of scientists have for the first time been able to depict the molecular changes in a protein that triggers cell death, a discovery that may lead to new treatments to control whether diseased cells survive or die. The finding was published in the journal Cell. For more information, watch the video explanation below: