Many traits unique to humans are thought to have originated in the genus Homo between 2.4 and 1.8 million years ago in Africa.

What are the evolutionary factors that drove them?

A large brain, long legs, the ability to craft tools and prolonged maturation periods were all thought to have evolved together at the start of the Homo lineage as African grasslands expanded and Earth's climate became cooler and drier. However, new climate and fossil evidence analyzed by a team of researchers suggests that these traits did not arise as a single package. Rather, several key ingredients once thought to define Homo evolved in earlier Australopithecus ancestors between 3 and 4 million years ago, while others emerged significantly later.

Researchers have announced the discovery of a gene, zic-1, that enables stem cells to regrow a head after decapitation in flatworm planarians.

The earthquakes in central Oklahoma since 2009 are likely attributable to subsurface wastewater injection at a handful of disposal wells -
Oklahoma earthquakes constitute nearly half of all central and eastern U.S. seismicity from 2008 to 2013, many occurring in areas of high-rate water disposal.

These are legacy drilling operations, not modern natural gas fracking.

The reduction of soil carbon stock caused by the conversion of pasture areas into sugarcane plantations is very common change in Brazil in recent years but those worried about the impact on CO2 can rest easy. It can  be offset within two or three years of cultivation.

The calculation by researchers at the Center for Nuclear Energy in Agriculture (CENA) of the University of São Paulo (USP) in collaboration with colleagues from the Luiz de Queiroz College of Agriculture (Esalq), also at USP, concluded, "Soil carbon stocks on land-use change process to sugarcane production in South-Central Brazil."

Acoustic vibrations – sound waves – are produced by radiation pressure inside stars. While physicists have long posited that young stars vibrate differently than older stars, a new study says it is the first to confirm these predications using concrete data from outer space. 

First author Konstanze Zwintz, a postdoctoral researcher at KU Leuven's Institute for Astronomy, and her colleagues studied the vibrations of 34 stars aged under 10 million years and sized between one and four times the mass of our sun.

The FDA released its long-awaited Draft Guidance on hospital-acquired pneumonia recently. Their guidance has not changed since I wrote a blog about my last meeting with the FDA antibacterial drug development task force back in September of last year.

To reiterate what I stated back then . . .

A couple of weeks ago I reported here about the new measurement of the Higgs boson mass produced by the ATLAS experiment. That determination, which used the full dataset of Run 1 proton-proton collisions produced by the LHC in 2011-2012, became and remained for two weeks the most precise one of the Higgs mass. Alas, as I wrote the piece I already knew that CMS was going to beat that result very soon, but of course I could not say anything about it... It ached a bit!

You know why soup tastes good - and your dogs love it too. It's bone marrow fat. Now it may be healthier to eat delicious.

A study has found that the fat tissue in bone marrow is a significant source of the hormone adiponectin, which helps maintain insulin sensitivity, break down fat, and has been linked to decreased risk of cardiovascular disease, diabetes, and obesity-associated cancers. 

Want to send a message to possible invaders? Pile dead bodies high and deep. A new species of wasp does just that.

This wasp with a unique nest-building strategy was discovered in the forests of southeast China. The "bone-house wasp" shuts off its nest with a chamber full of dead ants in order to protect its offspring from enemies, as shown by Michael Staab and Prof. Dr. Alexandra-Maria Klein from the Institute of Earth and Environmental Sciences of the University of Freiburg as well as scientists from the Museum für Naturkunde Berlin and the Chinese Academy of Sciences in Beijing.

No other such strategy has ever been discovered before in the animal kingdom.