A solar-powered airplane finished crossing the United States on Saturday, landing in New York City after flying over the Statue of Liberty during its historic bid to circle the globe, the project team said. The spindly, single-seat experimental aircraft, dubbed Solar Impulse 2, arrived at New York's John F. Kennedy International Airport at about 4 a.m. local time after it took off about five hours beforehand at Lehigh Valley International Airport in Pennsylvania, the team reported on the airplane's website. Such a pleasure to land in New York! For the 14th time we celebrate sustainability," said the project's co-founder Andre Borschberg on Twitter after flying over the city and the Statue of Liberty during the 14th leg of the trip around the globe. The Swiss team flying the aircraft in a campaign to build support for clean energy technologies hopes eventually to complete its circumnavigation in Abu Dhabi, where the journey began in March 2015. The solar cr...
The analysis of genomes from 101 ancient adults suggests the gene for breaking down the lactose sugar in milk was still rare in the Bronze Age. The results come as something of a surprise because the gene is widespread among modern Europeans. The research by an international team is published in Nature journal."It seems like the Bronze Age is the periThe findings illuminate a debate over migrations during the Bronze Age (3,000-5,000 years ago), which - according to the picture emerging from ancient DNA research - was a particularly dynamic period where the genetic diversity and distribution that we know today is basically formed," co-author Prof Eske Willerslev, from the University of Copenhagen, Denmark, told.
The study shows that people of European origin penetrated enmasse into Central Asia where they became known as the Sintashta culture. And a population from Europe's eastern periphery called the Yamnaya, who carried ancestry also found in Native Americans, pushed far into northern and central Europe. The team was able to look at some of the genetic characteristics of these ancient individuals. One thing that stood out was the scarcity of a variant in the gene (called LCT) that codes for lactase, an enzyme that breaks down lactose.
"The ability to drink milk is a very unique European feature - you also find it in a few African groups, but there it is due to different mutations," said Prof Willerslev.The ability in adulthood to break down lactose is rare or absent in most parts of the world. Those without the mutation can experience unpleasant side effects if they consume substantial amounts of milk.
"At the end of the Bronze Age, this genetic ability is still extremely rare," said Eske Willerslev, describing the result as a surprise.Researchers had previously linked the emergence of lactose tolerance to the Neolithic period, when domestic cattle were introduced to Europe by Anatolian farmers. But Neolithic genomes haven't turned up any evidence of an increase in the trait at this time.
"We see a slight increased frequency not in Europe but to the east, on the steppe. One possibility is that after the Bronze Age, this genetic ability was brought into Europe and is then selected for."
Comments
Post a Comment