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Over many, many years they smashed together to make fewer, bigger planets. In this case, I know the ingredients: flour, eggs, milk, water, butter. So I might just try mixing all these things together and baking them. David Reed is now the world's foremost expert on the evolution of lice. of, not only the head louse, but also of this little guy: pediculus humanus humanus, the body or clothing louse.
And those smashed together to form fewer, even bigger planets. I could try different orders, different combinations, different amounts, but what you get is not pí¢te í choux. He thinks the pests can solve all kinds of mysteries about our past, like when we started wearing clothes. To the naked eye it looks identical to the head louse, but there are a few key differences: it lives and lays its eggs only in clothes and bedding, and, unlike the head louse, the clothing louse can kill you.
Now, in a landmark discovery, chemist John Sutherland has created the conditions in which the building blocks of RNA, one of the key molecules of life and the probable precursor to DNA, assemble themselves naturally. How we got from here to here, we haven't exactly figured out yet. Then they have to be distinguished from Earth's rocks.
Hi, I'm Neil de Grasse Tyson, your host of NOVA science NOW, where this season we're asking six big questions. The Sun; the planets; our home, the Earth: what triggered their creation? But lately, we've found some intriguing new evidence that tells us our peaceful solar system might have started with a violent event. One trait stands out in nearly all meteorites: metal; they've got it. This meteorite hunting is a lot harder than it looks, and some days, you don't find any. Luckily, over the years, hunters have turned up more than 30 thousands specimens.
Correspondent Chad Cohen digs down deep into the roots of the tree and uncovers some groundbreaking research into how life first began. There are epidemic typhus, trench fever and relapsing fever.Where did the very first living thing on Earth come from? One team may have retraced a key step in the birth of life, itself. But where did this stable piece of real estate come from?Scientists have long argued that billions of years ago, life emerged on its own—but no one knows exactly how. We know that stars and planets, once upon a time, all started out like this, with enormous clouds of gas and dust. Some leave deep impacts in Earth, like one that blasted Arizona's Barringer Crater, 50,000 years ago. They can be as small as dice, reduced to a rocky cinder.I've come to the deserts of Arizona to try to track down some rare space rocks. Perfect place for hunting for meteorites: southern Arizona. So, can these space rocks tell us what triggered the event? It's made from three parts: a sugar, a phosphate and a single letter of the genetic code, a base. Knowing what chemicals it would take, the question was how to cook them together.Here at Arizona State's Center for Meteorite Studies, its director, Mini Wadhwa,... Each of these parts is made up of simple chemicals that existed on the early Earth, but nobody has been able to put them together, that is, until John Sutherland came along. And so they tackled the problem at hand: trying to make R. People have known the ingredients for some time now, but the recipe has not been really working out.
Once you've got the makings of a star, gravity draws leftover gas and dust into a giant swirling disk. Well, not everybody is buying the "supernova-as-a-creator" theory. has long been hailed as the fundamental molecule of life. Most of what we know about human evolution comes from these: the fossilized bones of our ancestors.