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Question

Polar Bears Have Irish Lineage

Some 50,000 years ago, modern polar bears split from a population of Irish brown bears.

© Daniel J. Cox / NaturalExposures.com
A genetic study found Irish roots for the polar bear and revealed the bear interbred with other bear species multiple times.
Today, polar bears live only on the northernmost stretches of ice and snow, but their roots may lie farther south -- in an area that is now Ireland.

Sometime within the last 50,000 years, suggests a new genetic study, modern polar bears split from a population of Irish brown bears. The finding both clarifies and complicates how well scientists understand polar bear evolution.

Scientists already knew, for example, that the giant white bears first evolved at least 110,000 years ago, with origins most likely in coastal Siberia. Based on the new results, though, it looks like polar bears then proceeded to interbreed with brown bears multiple times after they first diverged -- usually during periods when climate cooling or warming allowed the ranges of the two species to overlap.

Taking in new genes during these periods may have helped polar bears survive changing environmental conditions. Now, as climate warming pushes polar bears and brown bears closer together again, the study may offer some hope for the threatened polar bear's future.

"The results suggest that what is likely to happen in the future is exactly what has been observed: Their ranges are beginning to overlap, and they are hybridizing" said lead author Beth Shapiro, an evolutionary biologist at The Pennsylvania State University in University Park. "As long as polar bear habitat remains, there is a chance that the polar bear will survive."

Einstein

Dwarf Galaxies Orbiting The Milky Way Overturn Newton

© The Daily Galaxy

It turns out that we don't know everything about the universe. Shocking, we know, but you'd be surprised how often science writers, politicians, or intelligent design idiots confuse "non-omniscience" with "everything is WRONG!" Now some are saying that Newton screwed up, but at least their evidence is awesome: dwarf galaxies orbiting the Milky Way! The dwarf galaxies resemble systems cannibalized by the Milky Way billions of years ago to build up its stellar halo and thick disk, characterized as "crumbs from the galactic feast."

First off, Newton was never "wrong" - he was "right as far as it was humanly possible to be in the seventeenth century." You have to remember that he defined all the motion he ever saw with a pencil, and when he discovered the math didn't exist he just spent a chunk of his life inventing it - meanwhile, you use a supercomputer system to watch cats falling out of trees.

There wasn't a lot of near-light-speed motion at the time, nor any neutrinos, and it's important to remember that the people who build bridges don't go with general relativity or quantum mechanics - it's all the three laws of force, baby. You only find you need further theories when you look outside, and Professor Pavel Kroupa of the University of Bonn and colleagues have looked as outside as you can reasonably get: analyzing the motions of dwarf galaxies, thousands of starts orbiting the entire Milky Way. There they've found some fascinating contradictions.

Info

The Ultimate Time Travelers --Microbes Survive Millions of Years Traveling in Space

© The Daily Galaxy

In a unique experiment on a galactic scale, millions of bacterial spores have been purposely exposed to space, to see how solar radiation affects them and the results supported the idea that not only could life have arrived on Earth on meteorites, but that considerable material has flowed between planets.

Closer to home, scientists have analyzed aerial dust samples collected by Charles Darwin and confirmed that microbes can travel across continents without the need for planes or trains - rather bacteria and fungi hitch-hike by attaching to dust particles. Their results clearly show that diverse microbes, including ascomycetes, and eubacteria can live for centuries and survive intercontinental travel.

In a paper published in Environmental Microbiology, Dr. Anna Gorbushina (Carl-von-Ossietzky University, Oldenburg, Germany), Professor William Broughton (University of Geneva, Switzerland) and their colleagues analyzed dust samples collected by Charles Darwin and others almost 200 years ago.

Recent space-centric studies have shown that some rock-inhabiting organisms, known as "endoliths," might be able to survive a trip through space and a plunge through a planet's atmosphere to the surface. However, nobody knew whether these organisms could survive the initial trip into space.

An international team of researchers, led by Gerda Horneck of the Institute of Aerospace Medicine in Cologne, Germany, selected a number of hardy microbes from Earth and tested their ability to hitchhike aboard rocks similar to Martian meteorites.

Fish

Gray Whales Likely Survived the Ice Ages by Changing Their Diets

Image
© iStockphoto/Marshall Bruce
A grey whale mother and calf off the coast of Baja California. If ancient gray whale populations migrated and fed the same as today's whales, what happened during the Ice Ages, when their major feeding grounds disappeared?
If ancient gray whale populations migrated and fed the same as today's whales, what happened during the Ice Ages, when their major feeding grounds disappeared? UC Berkeley and Smithsonian paleontologists argue that gray whales utilized a range of food sources in the past, including herring and krill, in addition to the benthic organisms they consume today. As a result, pre-whaling populations were two to four times greater than today's population of around 22,000.

Gray whales survived many cycles of global cooling and warming over the past few million years, likely by exploiting a more varied diet than they do today, according to a new study by University of California, Berkeley, and Smithsonian Institution paleontologists.

The researchers, who analyzed California gray whale (Eschrichtius robustus) responses to climate change over the past 120,000 years, also found evidence to support the idea that the population of gray whales along the Pacific Coast before the arrival of humans was two to four times today's population, which stands at about 22,000. The whale is considered a conservation success story because protections instituted as early as the 1930s have allowed populations to rebound from fewer than 1,000 individuals in the early 20th century, after less than 75 years of systematic whaling.

Telescope

ESA unveils billion pixel camera that will map the Milky Way

That's not a camera: this is the camera

The European Space Agency has announced the completion of the camera that's to be used in its Gaia mission: a billion-pixel mosaic comprising 106 individual CCDs in a 0.5x1 meter array.

Assembled in May and June at Astrium's facility in Toulouse, the camera is designed to map around a billion stars when Gaia's five-year mission begins in 2013. The CCDs were developed by UK company e2v Technologies, with each measuring 4.7x6cm.

2 + 2 = 4

Boffins build nanowire lasers from nappy-rash cream

Spread here for ultraviolet diodes

A new breakthrough in zinc oxide - based semiconductor nanowire lasers may support applications that range from killing viruses to stuffing more stuff on a DVD.

"People in the zinc oxide research community throughout the world have been trying hard to achieve this for the past decade," the leader of the research team, Jianlin Liu, said in a statement announcing the breakthrough. "This discovery is likely to stimulate the whole field to push the technology further."

Pardon our provincialism, but the existence of a zinc oxide research community was news to us. Perhaps it shouldn't have been, in light of the many and varied uses of the compound, from diaper-rash ointment to cigarette filters to vulcanization.

Telescope

Backyard Stargazers' Guide: Stars Make Heavy Metal in Slow, Ferocious Burn

© NASA
In the beginning, there was just hydrogen and helium. Things were light. Gold and lead and other heavy elements were not created when the universe sprang into existence with a Big Bang.

Since then, a lot has happened inside stars to create the other ingredients needed to make planets, people, wedding rings and fishing weights.
Astronomers know this, and they have a long-standing theory about how the giant element factories - stars - operate. But within this theory is a subtheory describing how the heaviest elements originate, those weighing as much as iron or more. The subtheory is on less solid ground, and scientists continue to search for evidence to support it.

Research published in the journal Nature supports the idea that a lot of the heavy metal in the world today is the product of a slow burn, deep inside stars of a certain type.

Satellite

Space Telescope Captures Rare View of a Star Engulfing Another Star

Image
© ESA/AOES Medialab
A clump of matter from a massive blue supergiant star (Left) is being pulled by an intense gravitational field of a neutron star (Right).
An European Space Agency (ESA) telescope has captured extreme outburst in a star which astronomers believe was caused by the star trying to eat another star, much larger in size.

ESA's XMM-Newton space observatory has watched a faint star flare up at X-ray wavelengths to almost 10 000 times its normal brightness, ESA said in a statement.

According to ESA scientists, the flare took place on a neutron star, which is formed when a giant star collapse during supernova explosion.

About 10 km in diameter, a neutron star is so dense that it generates a strong gravitational field intense enough to pull a clump of matter emitted by giant stars.

2 + 2 = 4

Liverpool Telescope challenges galaxy formation theory

© Unknown
An international team of astronomers, including Dr Chris Simpson of Liverpool John Moores University's (LJMU) Astrophysics Research Institute (ARI), have used the Liverpool Telescope, owned and operated by the ARI, to help discover a black hole more than a billion times the mass of our Sun, seen when the Universe was only 770 million years old.

Although no light is emitted by the black hole itself, its strong gravity pulls in surrounding gas that is heated up and shines as what astronomers call a quasar. The existence of such a massive black hole so soon after the Big Bang presents a challenge to theories that attempt to describe the formation of galaxies.

The quasar, known as ULAS J1120+0641 based on its location in the sky, was originally identified in images of the sky taken by the United Kingdom Infrared Telescope (UKIRT) as part of the UKIRT Infrared Deep Sky Survey (UKIDSS). UKIDSS has observed approximately 5% of the sky and the team select quasar candidates based on their colours in the survey. These candidates are then followed up with the Liverpool Telescope to weed out contaminants.

Beaker

Hydrogen peroxide found in interstellar space

© TG Daily
Hydrogen peroxide has been found for the first time in space, and astronomers are excited - not because it indicates that aliens are bottle blondes, but because it gives clues to how water may be formed.

The discovery was made with the Atacama Pathfinder Experiment telescope (APEX), situated on the 5000-metre-high Chajnantor plateau in the Chilean Andes, which observed a region in our galaxy close to the star Rho Ophiuchi, about 400 light-years away.

This area contains very cold, dense clouds of cosmic gas and dust, in which new stars are forming. While the clouds are mostly made of hydrogen, they contain traces of other chemicals.

"We were really excited to discover the signatures of hydrogen peroxide with APEX," says Per Bergman, astronomer at Onsala Space Observatory in Sweden.

Comment: Indeed, cosmic dust holds many secrets, one of which is that dessicated bacteria and other microbes appear to be seen throughout interstellar space as well. The interested reader might want to check out Hoyle and Wickramasinghe's Analysis of Interstellar Dust.