For an Octopus, Seeing the Light Doesn’t Require Eyes

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The New York Times, May 20, 2015

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Octopuses, squid and cuttlefish — a group of mollusks known as cephalopods — are the ocean’s champions of camouflage.

Octopuses can mimic the color and texture of a rock or a piece of coral. Squid can give their skin a glittering sheen to match the water they are swimming in. Cuttlefish will even cloak themselves in black and white squares should a devious scientist put a checkerboard in their aquarium.

Cephalopods can perform these spectacles thanks to a dense fabric of specialized cells in their skin. But before a cephalopod can take on a new disguise, it needs to perceive the background that it is going to blend into.

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Bamboo Mathematicians

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PHYLLOSTACHYS BAMBUSOIDES, A SPECIES OF BAMBOO WITH A 120-YEAR FLOWERING CYCLE. PHOTO BY EMMANUEL LATTES, ALAMY

In the late 1960s, a species of bamboo called Phyllostachys bambusoides–commonly known as the Chinese Mainland Bamboo or Japanese Timber Bamboo–burst into flower. The species originated in China, was introduced to Japan, and later into the United States and other countries. And when I say it flowered, I mean it flowered everywhere. Forests of the plant burst into bloom in synchrony, despite being separated by thousands of miles. If, like me, you missed it, you will probably not live to see it happen again. The flowers released pollen into the wind, and the fertilized plants then produced seeds that fell to the ground. The magnificent bamboo plants, which can grow 72 feet tall, then all promptly died. Their seeds later sprouted and sent up new plants. The new generation is now close to fifty years old and has yet to grow a single flower. They won’t flower till about 2090.

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Reverse Engineering Birds’ Beaks Into Dinosaur Bones

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The New York Times, May 12, 2015

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Birds evolved from dinosaurs 150 million years ago, a slow but thorough transformation. Their bodies gained aerodynamic feathers, their digits fused into wings, and they acquired a beak used to gather food.

We can see some details of this evolutionary marvel in the fossil record. Yet even the most exquisitely preserved fossil can’t tell us which pieces of DNA had to change in order to turn ground-running dinosaurs into modern birds.

Some researchers are now trying to pinpoint those genetic changes with experiments on chicken embryos. If the scientists succeed, they should eventually be able to reverse the evolution of birds — and then they may be able to engineer animals more at home in “Jurassic Park” than in a henhouse.

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Can Scientists Turn Birds Back Into Dinosaur Ancestors?

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PHOTO BY THOMAS HAWK VIA CREATIVE COMMONS

We know they evolved from dinosaurs about 150 million years ago, but it remains to be discovered precisely how the DNA of ground-running dinosaurs changed–a transformation that turned arms into wings, produced aerodynamic feathers, and created a beak. It’s possible that some clues to those genetic changes can be found in living birds themselves. By blocking some of the recently evolved steps in the development of bird embryos, we might be able to get birds to grow some dinosaur anatomy.

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Under the Sea, a Missing Link in the Evolution of Complex Cells

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The New York Times, May 6, 2015

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Unlike bacteria, humans have big, complex cells, packed with nuclei containing DNA and mitochondria that produce energy. All so-called eukaryotes share our cellular complexity: animals, plants, fungi, even single-celled protozoans like amoebae.

Scientists estimate that the first eukaryotes evolved about 2 billion years ago, in one of the greatest transitions in the history of life. But there is little evidence of this momentous event, no missing link that helps researchers trace the evolution of life from simple microbes to eukaryotes.

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