Science News

Headlines

. Gemstones made in the lab have many uses, not just as gems
. Some DNA in modern humans was passed down from Neanderthals
. Frogs learned to jump first, before they mastered the touchdown
. Google Earth images locate a crater in Egypt from a recent (few
thousand year) meteorite hit
. How swarming locusts together decide where to go

Read more about some of them below.
Gemstones made in the lab have many uses, not just as gems
Usually, gemstones form below Earth's surface. They can stay buried for many millions of years. But scientists like Tom Chatham in San Francisco, U.S., are creating gemstones on their own. They do this with entirely new processes. Lab-made gems have the same appearance and basic chemical structures as the natural ones, and they can be produced in months or even days.
Because these gems are created in the laboratory, researchers can control the gems' formation very carefully. Some lab-grown gems are even purer or tougher than natural gemstones. And the gems are good for more than just jewelry. They can be used to make tools, such as lasers and drills. Lab-made diamonds could even help scientists improve electronic devices or detect dangerous bacteria in drinking water.
Rubies are special because they can create laser beams. If you place a ruby rod between two mirrors and flash a very intense light at it, the ruby will shoot out a beam of red light. This is a laser, that has hundreds of uses in science research and industry.
Emeralds and even diamonds are now made this way. Diamonds are a little different from other gemstones because it takes huge amounts of pressure for diamonds to form.
In fact, diamonds are made only of carbon, a chemical element found in all living things. If you arrange carbon atoms in layers like sheets of paper, you get graphite -- a soft material used in pencil lead. But if you connect each carbon atom to four other carbon atoms in a three-dimensional structure, you get diamond -- an incredibly hard material.
Diamond is so hard that it is used to cut rock and drill for oil. If you have ever had a cavity filled at the dentist, a diamond-tipped drill may have been used to remove part of your tooth.
Diamond lets heat pass right through it, so a diamond stays cool. And diamond is very stiff, meaning that it is hard to bend. It really is Nature's extreme material.
Some of these properties could make diamond useful in cell phones. These phone uses parts called acoustic filters. Currently, these filters can be made of materials such as quartz or ceramic. Each filter must vibrate at a certain rate in order for the phone to work. Some filters have to vibrate more than a billion times per second.
Because diamond is so stiff, it can vibrate at a very fast rate. Researchers are now working on creating tiny diamond filters, smaller than the width of a strand of hair. These filters could make the cell phone use less power, so the battery would last longer.
There seem to be really too many uses of these precious stones to just use them as jewelry!

Some DNA in modern humans was passed down from Neanderthals

The Neanderthals, now extinct, are ancient members of the human family tree. Neanderthals appeared about 300,000 years ago and the modern humans, Homo sapiens, appeared about 250,000 to 200,000 years ago. No other extinct species is a closer relative to humans than Neanderthals.
Neanderthals probably walked on two legs and lived in what are now Europe, Asia and the Middle East until they vanished, 30,000 years ago. They may have looked a lot like other human species and lived in some of the same regions, but scientists have long thought that Neanderthals and early modern humans had little to do with each other. But the new study suggests that the two species may have become close enough to have children together.
The Neanderthals may be long gone, but researchers can learn a lot about them by studying genetic information left behind, in their bones.
One year ago, a team of scientists analyzed and reported the entire genetic code for Neanderthals.
The entire genetic code of a species is called its genome, and it is a list of all the important genes in the species' DNA. These genes contain the instructions for how to build proteins, and proteins perform specific functions in a cell. When scientists produced the first version of the Neanderthal genome, they said it was very unlikely that Neanderthals and humans had ever interbred.
In the new study, researchers investigated ancient bones to compare the genetic material of Neanderthals to genetic material in modern people. According to the study, 1 to 4 percent of the DNA in modern people from Europe and Asia came from the Neanderthals.
For the new study, Reich and his colleagues used genetic material from the bones of Neanderthals, found in a cave in Croatia. The scientists compared those genes to the genomes of five modern humans from different parts of the world: China, France, Papua New Guinea, southern Africa and western Africa.
The results were surprising: not everyone had the same Neanderthal connection. The two people from Africa did not have Neanderthal DNA, but the other three did -- even though Neanderthals never lived in China or Papua New Guinea. The modern people from those areas had just as much Neanderthal DNA as the person from Europe.
Archaeologists have found skeletons in Europe that look like both Neanderthals and modern humans -- which suggests the two species mixed. The new study is further evidence in this direction.

Frogs learned to jump first, before they mastered the touchdown

All of you must have seen leaping frogs. But do they all leap the same way?
Some species of primitive (long existing) frogs belonging to a family called Leiopelmatidae are good jumpers but are amazingly clumsy at touching down and can even tumble over at times.
More evolutionarily advanced species include Lithobates pipiens, the northern leopard frog, and Bombina orientalis, the oriental fire-bellied toad. Both these modern creatures pull their hind limbs back toward their bodies mid-way through the jump. This allows them to more quickly position their legs for another jump. These frogs consistently landed smoothly on their forelimbs.
The earliest frogs probably used leaping as a way to escape predators and return to the water, he notes. In such a scenario, how a frog lands isn't as important as escaping. But as some ancient species of frogs became more adapted to life away from water, efficient landings allowed hops to come in quick succession.
Landing successfully is what makes the next hop possible -- good for both evading predators and chasing prey.

How swarming locusts together decide where to go
Desert locusts normally live in arid parts of Africa and Asia but can explode over millions of square kilometers during plagues, as happened during the late 1980s. Researchers understand much of the basic biology behind locust swarms -- even how the insects change color as they mass together -- but the physics describing their collective behavior has been something of a mystery.
Mathematicians have now figured out the dynamics that drive locusts across the landscape, devastating everything underfoot. The bad news is that people will never be able to predict where they will go!
The new analysis suggests that random factors accumulate and influence how swarming locusts collectively decide to change course. This can make it impossible to predict their behaviour, but the scientists have not stopped trying.

--Compiled from several sources