Friday turkey break

Pumpkin Pie Season Again

Every Friday at Nothing in Biology Makes Sense! our contributors pass around links to new scientific results, or science-y news, or videos of adorable wildlife, that they’re most likely to bring up while waiting in line for a latte — or while recovering from a turkey-induced coma.

From Jon: Psychiatrists consider one possible reason why genes for psychiatric disorders persist in spite of their selective disadvantages, and find some supporting evidence.

Another theory is that the genetic mutations that cause a disorder in one person somehow make that person’s sibling more likely to have children. In a situation like that, the mutation offers a net benefit to a person’s family.

A team of Swedish and British scientists recently tested these theories by comparing the rates at which people suffering from mental illness have kids to those of their siblings. The data came from a medical database of more than 2 million Swedes.

From Noah: A new comprehensive study finds that, on average, new species aren’t formally described and named until 21 years after samples are first collected.

Given the recent increase in extinction rates due to human activities, however, a species can go extinct between the time it is collected and when it is written up. Many of the new species being identified are already endangered, notes Lee Grismer, a biologist at La Sierra University in Riverside, California. “A median shelf life of 12 years is catastrophic,” he says. “We will not save biodiversity with this.” Fontaine agrees: “It’s difficult to protect things we don’t know about.”

And from Sarah: A helpfully complete fossil lets paleontologists clarify the relationship between modern great white sharks and even bigger prehistoric sharks.

“The nice thing about this new species is that we have an articulated set of jaws which almost never happens and we could see that the third anterior tooth is curved out, just like in the tooth row of mako sharks today,” [Professor Dana Ehret of Monmouth University] said.