<p>The genetic homeland of Native Americans is a small mountainous region in southern Siberia, a new study suggests.</p>

<p>For mammals, evolving into bigger sizes takes a lot longer than shrinking, new evolution study shows.</p>

Hubble captures a Milky Way "twin," winds shape Mars lava fields, stars carve a nebula's face, and more in the week's best space pictures.

<p>A vast iceberg is splitting from Antarctica, thanks to a giant crack in a glacier that's "really important" to sea level rise.</p>

<p>The likely rocky planet orbits squarely in its star's habitable zone, making it a prime candidate for life, astronomers report.</p>

<p>Two tiny satellites add to the planet's swarm of "backward" moons and bring the full Jovian family up to 66 natural satellites.</p>

<p>Bacteria in water-filled Caribbean sinkholes could offer clues to what might live on icy moons such as Europa, scientists say.</p>

<p>Early spring or long winter? "Immortal" rodent Punxsutawney Phil has made his forecast. Get the odd facts behind Groundhog Day 2012.</p>

A spiny cucumber and a nanotube ''city'' feature among the winners of the 2011 International Science and Engineering Visualization Challenge.

See the wreck of the <em>Hunley—</em>the world's first submarine to sink an enemy ship—finally unveiled after 11 years in a steel truss.

<p>With ancient origins, "immortal" rodent Punxsutawney Phil rules Groundhog Day 2012. Get the surprising facts behind winter's wackiest U.S. weather prediction.</p>

<p>A fossil croc sporting an odd head "shield" has been found in Morocco, paleontologists say.</p>

See the pictures we love, as chosen by National Geographic photo editors—from a too plush penguin to a pantsless pedestrian.<p> </p>

<p>For the first time, a NASA spacecraft has directly observed particles that came from beyond our solar system, astronomers announced.</p>

<p>A new analysis of Kepler data hints that scientists can add more than 400 new worlds to the NASA mission's confirmed discoveries.</p>

<p class="Body">A new report highlights advancements in recycling technology and predicts growth in treatment programs, if people can get beyond ick factor.</p>

<p>The first picture of a planet outside our solar system may actually depict a swirl of space dust, a new study suggests.</p>

<p>Invasive Burmese pythons are likely behind "dramatic" declines of the swamp's mammals—from rabbits to bobcats—new research suggests.</p>

<p>A new population of one of the world's rarest primates has been found in a Colombian park, conservationists announced today.</p>

<p>What's more, the Scottish island complex may have been the model for England's famous stone-circle site, new data suggest.</p>

<p>By zapping a scrap of metal with superpowerful x-rays, scientists created plasma that rivals the sun for heat.</p>

<p>The recent uptick in solar flares and other sun activity has been causing orbiting debris to fall faster, a NASA scientist reports.</p>

Plasma arcs over the sun, Earth shines in high resolution, a colorful halo surrounds the moon, and more in the week's best space pictures.

<p>Clouds of slow-moving charged particles reach from the top of Earth's atmosphere to a quarter of the distance to the moon, new data show.</p>

<p>It may be barren, but California's Ubehebe Crater is anything but dead, according to a new study.</p>