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...
Sixty-five million years ago, an asteroid is believed to have crashed into Earth. The impact wiped out huge numbers of species, including almost all of the dinosaurs.One group of dinosaurs managed to survive the disaster. Today, we know them as birds.
The idea that birds evolved from dinosaurs has been around since the 19th century, when scientists discovered the fossil of an early bird called Archaeopteryx. It had wings and feathers, but it also looked a lot like a dinosaur. More recent fossils look similar. But these early birds didn't look the same as modern ones. In particular, they didn't have beaks: they had snouts, like those of their dinosaur ancestors.
To understand how one changed into another, a team has been tampering
with the molecular processes that make up a beak in chickens.
By
doing so, they have managed to create a chicken embryo with a
dinosaur-like snout and palate, similar to that of small feathered
dinosaurs like Velociraptor. The results are published in the journal Evolution.
The
team's aim was to understand how the bird beak evolved, because the
beak is such a vital part of bird anatomy. It has been crucial for their
success. The 10,000 or more bird species occupy a wide range of
habitats, and many have specialised beaks to help them survive.
But they did not set out to create a "dino-chicken", say lead authors Bhart-Anjan Bhullar of Yale University in New Haven and Arhat Abzhanov of Harvard University in Cambridge.
"Whenever you examine an important evolutionary transformation, you want to learn the underlying mechanism," says Bhullar. The beak is also the part of the avian skeleton that has "diversified most extensively and most radically", says Bhullar.
Despite
this diversity – ranging from flamingos to pelicans - very little work
has been done to figure out "what the heck a beak actually is", he adds.
"I
wanted to know what the beak was skeletally, functionally and when this
major transformation occurred from a normal vertebrate snout to the
very unique structures used in birds."
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