How did small bands of nomadic Mongol horsemen unite to conquer much of the world within a span of decades? A whole book could be written on that, and it probably will be, if a new "Indiana Jones" movie gets made using Genghis Khan.

The reasons are numerous and involve many different things but climate change is a less-considered one. Yet researchers studying the rings of ancient trees in mountainous central Mongolia say his conquest was likely due to nice weather. 

Research using satellite observations and ice thickness measurements gathered by NASA's Operation IceBridge is giving new insight into one of the processes causing Greenland's ice sheet to lose mass.

A team of scientists calculated the rate at which ice flows through Greenland's glaciers into the ocean, which gives a clearer picture of how glacier flow affects the Greenland Ice Sheet and shows that this dynamic process is dominated by a small number of glaciers.

Operation IceBridge has been measuring the thickness of many of Greenland's glaciers, which allowed researchers to make a more accurate calculation of ice discharge rates. Researchers calculated ice discharge rates for 178 Greenland glaciers more than one kilometer (0.62 miles) wide.

Aggressive marketing by raw milk proponents has included claims that raw milk is easier to stomach for for lactose-intolerant people but a pilot study from the Stanford University School of Medicine shows no meaningful difference in digestibility between raw and pasteurized milk.

It's no surprise that natural selection does not always take an evolutionary time scale. 

When thousands of knights died during the Crusades at Acre, natural selection was being channeled. Yes, there were still other mechanisms of evolution but when the available pool of people is changed, positive selection is changed also. Pinpointing that on a time scale can be tough but there has been much research into the factors that have influenced the human genome since the end of the last Ice Age and a team of anthropologists, geneticists and archaeologists have analyzed ancient DNA from skeletons and found that selection has had a significant effect on the human genome even in the past 5,000 years.

Alan Turing was long famous in computer science and then became notable due to his sexuality and its controversy in England. Less well known is his work in biology and chemistry.

During World War II, Turing helped cracked the German Enigma Code, which made it possible to decipher enemy transmissions.  After the war, he was convicted of homosexuality — a criminal offense in England — and sentenced to chemical castration.  Shortly after his trial, and before he killed himself in 1954, he published a biology paper, "The Chemical Basis of Morphogenesis."

A faster and less expensive form of radiotherapy, called Stereotactic body radiotherapy (SBRT), for treating prostate cancer may come with a higher rate of urinary complications.

The standard external beam radiation therapy for prostate cancer is currently intensity modulated radiation therapy (IMRT). Stereotactic body radiotherapy delivers a greater dose of radiation per treatment than IMRT so  patients receiving SBRT can complete an entire course of treatment in one to two weeks, compared to seven to nine weeks for IMRT. 

The worldwide love affair with subsidized green energy is fading fast but that shouldn't be taken to mean the science is not solid. 

In America, new power plants are difficult to get built and as a result the cost of electricity has gone up while the supply has gone down. Yet the government seems to still want to fast track alternative energy and regulations that allow small biomass plants may also help solve a grid problem that solar and wind energy only make worse.

Small biomass power plants that can fit on a farm and can be built at relatively low cost may be better than giant wind and solar plants that are opposed by environmental groups.

There's a cosmic war happening between
highly luminous O-type stars and nearby protostars in the Orion Nebula
.

The Orion Nebula is home to hundreds of young stars and even younger protostars known as proplyds. Many of these nascent systems will go on to develop planets, while others will have their planet-forming dust and gas blasted away by the fierce ultraviolet radiation emitted by massive O-type stars that lurk nearby.

Exaggerated health claims are not convincing the public, and "medical" marijuana has become something of a running cultural joke, but there is an upside to more pot - less cocaine use. Meth too, according to advocates at the RAND Drug Policy Research Center. 

Or at least a group is correlating the two. Methamphetamine and cocaine consumption increased during the first half of the last decade and then dropped in the latter half. Marijuana use increased significantly during that time, according to a new report.

When advocates want governments to take over some aspect of society, the argument is often an economic one - the money saved will be a suitably cosmic number.

Yet in the trenches of government-run industries the reality is much different. Taxes are finite so committees learn to cut costs where they can. Older people, perhaps because they have already led full lives, are being denied proper access to cancer care, according to an editorial by Queen's University Belfast academic Professor Mark Lawler of the Centre for Cancer Research and Cell Biology.