Month: November 2016

Enlarge / DENVER, CO - JULY 01 Former GOP vice presidential candidate Sarah Palin speaks during the 2016 Western Conservative Summit the Colorado Convention Center in Denver, July 01, 2016. It is the 7th annual Western Conservative Summit. (Photo by RJ Sangosti/The Denver Post via Getty Images) (credit: RJ Sangosti / Getty Images)

The US government's science efforts are split across a variety of agencies. Some are obvious, like the EPA, the Department of Energy, and the Department of the Interior, which oversees the National Parks and Endangered Species Act. But others are less so. For example, the Commerce Department includes the NOAA, or the National Oceanic and Atmospheric Administration, while the National Institutes of Health falls within the Department of Health and Human Services.

The people who run these agencies will have major say over the US' research priorities for the next four years, and they'll determine what role science plays in making policy decisions. So, as the Trump transition team begins the work of vetting potential candidates, the rumored names may say a lot about what we can expect.

A lot of these rumors are preliminary enough that they essentially tell us nothing. For example, possible candidates floated for Commerce Secretary include everyone from the Republican National Committee finance chair (Lew Eisenberg), to two different business executives, to several of Trump's former primary opponents like Chris Christie, Mike Huckabee, and Rick Perry. The NOAA keeps one of the US' two temperature records used for climate monitoring (NASA keeps the other), and it tracks the ocean's health. (It may also get all of NASA's earth sciences research.) But it's hard to guess whether any of these figures would pay much attention to these activities, much less make major revisions in them.

Enlarge (credit: Flickr user leted)

It's now clear that our ancestors, upon leaving Africa, interbred with the Neanderthals and Denisovans, archaic humans that occupied Europe and Asia. The first offspring of those pairings would have had equal amounts of their two ancestral legacies: one chromosome in each pair would be modern human, the other archaic. But most of that archaic legacy is now gone, down to about two percent from the initial 50. What happened?

People have been considering a number ideas. These range from the simple—a large and growing modern human population simply swamped the archaic genes—to more complex situations such as limited reproductive compatibility between the two genomes. But a new paper suggest something in between the two. Many Neanderthal genes might be slightly deleterious, the research suggests, but the Neanderthal populations weren't large enough to get rid of them.

It's difficult to understand the fate of Neanderthal genes, since we don't have any sense of how well the offspring of these matings did. All indications are that the instances of successful interbreeding were rare (with success here defined as offspring that passed on their genes as well). Since modern humans were expanding into new territories and increasing their population accordingly, it may simply be that the Neanderthal genes were diluted as their carriers continually mated with people who were largely or entirely modern.