Monday, 20 May, 2013

How do homing pigeons find their way on their amazing migrations? For a decade, scientists thought iron-bearing nerve cells in the beak can detect Earth’s magnetic field. But those iron granules are in immune cells. So how do the birds do it?

Returning to the site of a classic “first forest” site, New York scientists have found extra complexity: three fossilized trees-like species aged almost 400 million years. One find, a vine-like monster, may be a direct descendant of all seed-bearing trees!

The ocean’s most valuable fish are caught in a vise. Areas known as dead zones are encroaching on their living zones and pinning them closer to the surface, where they are more vulnerable to becoming the day’s catch. The predicament is yet another side effect of climate change.

A crash course in “sink or swim” teaches computerized robots to adapt to changing circumstances. When taught by “directed evolution,” robots that started without legs learned to walk sooner than robots that started with legs! Can you explain?

Lake Vostok could house ancient bacteria, but we already know that bacteria can live in boiling water or light up a glowing squid. Countless weird-and-weirdest critters live between grains of sand… Curious about biology’s strange shelf?

Can pigeons learn an abstract mathematical rule? Apparently, according to a new study, which asked pigeons to place, five blue dots and eight green squares, in ascending order. Now we know birds and primates can both do this, but where and why did this ability originate?

Scientists thought wings were the first evidence of flight. But plenty of falling ants can glide back to “their” tree to avoid being devoured on the forest floor. If an ant’s brain and body are able to detect its position and change its flight path, is gliding the first flight?

In just a moment, our brains can go from calm, deliberate and focused, to alert, agitated and aroused. New neural networks get activated during the transition. Now a study of the fight-or flight-response fingers a common hormone in triggering the brainwide changes.

For 15 years, we’ve presented the science behind the news. The Why Files are accurate, engaging, entertaining and educational. Check our links from national science teaching standards to specific Why Files — all 750 of them! Whether it’s geology or archaeology, weather or human behavior, The Why Files has it covered.

Plain-tailed wrens in the Andean cloud forest sing a complex, two-part song, where timing is everything. New research shows that both parties keep a memory of the full song in their brain, even though they only sing half of it.

Bacteria can help or harm their hosts. Now we hear how one genus of bacteria can multiply fly reproduction. In this symbiosis, both parties benefit. This bacterium also alters insect immunity, and could lead to new tactics for killing horrific parasites.

athogens can change the behavior of their hosts — and now we see that a single viral gene forces a caterpillar to climb a tree before it dies. From that high vantage, the virus can infect more caterpillars. It’s nifty and thrifty, unless you’re a gypsy moth!

78 million years ago, a pregnant predator of the Cretaceous ocean died and sank to the sea floor. Today, her fossil gives the first proof that plesiosaurs, one of the commonest and baddest marine reptiles of the era, did not lay eggs. It gave birth.

Hitting the road? What could be more enlightening than gawking at a cave, exploring a desert, or eyeballing the largest telescope in the world? Need proof that science is not just books and websites or equations and software? Get moving!

Long ago, nature devised the hinge and ball and socket for appendages like legs and wings. The screw is the latest simple machine to be discovered in nature. Why do weevils, a type of beetle, have a screw? How does it help weevils survive their 3-D world?