Science Sunday Roundup: Dolphins, Polar Bears, Chimps & Giant Inspects

For dolphin mothers, successful parenting is as much a matter of having good friends as it is having good genes. Research in Australia further confirms the importance of community to dolphin life -- and perhaps to animals in general.

For 25 years, the researchers have made detailed observations of bottlenose dolphins in Australia's Shark Bay, a one-of-a-kind dataset that has allowed them to chart the relatedness of dolphin mothers and map their habits of social association, then correlate these patterns to how well their offspring survived childhood. As would be expected, calves born to mothers from reproductively successful families tended to do well, while those from less-fit families tended to hang out with successful mothers.

* * * * *

Polar bears are the poster children for the impact of climate change on wildlife. Despite the amazing rate at which they have evolved -- they split off from brown bears as recently as 150,000 years ago -- their future may be bleak because their seal-killing skulls are surprisingly weak.

As the world warms and the Arctic ice starts to disappear, the polar bear's realm has started to become more temperate, reducing the number of suitable sites for building dens or foraging for seals. Meanwhile, brown bears from the south are already encroaching into their territory. With stronger skulls and teeth better suited to a varied diet, these invaders may present a significant challenge to polar bears.

* * * * *

Not surprisingly (to me anyway), humans are not the only species to prefer to use their right hand, and chimpanzees also share the trait.

This feature had traditionally been considered exclusively human and had been believed to be caused by asymmetries in the human brain that are related to the realization of complicated activities that require the use and coordination of both hands, but new research suggests that both species share factors that modulate brain function.

* * * * *

Ignoring warnings from those scary 1950s sci-fi horror movies, scientists are creating giant insects in their laboratories.

The insects in those movies were irradiated monsters and the scientists often evil geeks, while today's geeks are growing big bugs for a more benevolent reason -- figuring out why different insect groups respond to changes in atmospheric oxygen differently. Ancient oxygen levels apparently were much higher, which may be why there were dragonflies with 28-inch wingspans.