all Department of Organismic and Evolutionary Biology stories

Orphan army ants join nearby colonies

404132862 — Wed, 04 Nov 2009 00:01:00 -0500

A new analysis of extinct sea creatures suggests that the transition from egg-laying to live-born young opened up evolutionary pathways that allowed these ancient species to adapt to and thrive in open oceans.

The evolutionary sleuthing is described today in a letter in the journal Nature by scientists at Harvard and the University of Reading who also report that the evolution of live-born young depended crucially on the advent of genes — rather than incubation temperature — as the primary determinant of offspring sex.

Freshwater fish at top of food chain evolve more slowly

404132862 — Thu, 30 Jul 2009 16:23:11 -0400

Since evolving to eat other fish, freshwater fish at the top of the food chain have remained relatively unchanged compared with their insect- and snail-eating cousins, according to new research.

Scientists report in the journal Evolution that once these fish, known as centrarchids, became top predators in aquatic ecosystems, natural selection put the brakes on their evolution.

Maternal, paternal genes’ tug-of-war may last well into childhood

404132862 — Tue, 28 Jul 2009 11:32:19 -0400

An analysis of rare genetic disorders in which children lack some genes from one parent suggests that maternal and paternal genes engage in a subtle tug-of-war well into childhood, and possibly as late as the onset of puberty.

Trading energy for safety, bees extend legs to stay stable in wind

50443248 — Tue, 02 Jun 2009 16:10:05 -0400

New research shows some bees brace themselves against wind and turbulence by extending their sturdy hind legs while flying. But this approach comes at a steep cost, increasing aerodynamic drag and the power required for flight by roughly 30 percent, and cutting into the bees’ flight performance.

The findings are detailed in the Proceedings of the National Academy of Sciences.

Cassandra Extavour and Gonzalo Giribet

404132862 — Thu, 21 May 2009 19:48:23 -0400

Chance favored expedition leader in ‘missing link’ discovery

50443248 — Fri, 24 Apr 2009 11:14:12 -0400

A graphic in an undergraduate geology textbook serendipitously led to the 2004 discovery of the missing link between fish and land animals far in the Canadian Arctic, one of the creature’s discoverers said during an April 16 lecture at Harvard.

Neil Shubin, a professor at the University of Chicago and leader of the expedition that discovered Tiktaalik roseae, dedicated his career to finding an intermediary between lobe-finned fishes, which existed some 380 million years ago and early land animals, the first of which is thought to have existed 365 million years ago.

The way of the digital dodo

50443248 — Thu, 19 Feb 2009 14:33:54 -0500

The laser light glowed brilliant red, forming a moving line as it bounced information from the dodo’s bones back into the high-tech scanner sitting on a tripod on the Museum of Comparative Zoology’s (MCZ) fifth floor.

Again and again, the red line traced the contours of the skeletal bird, one of just a handful of complete skeletons of one of the world’s most famous cases of human-caused extinction.

The evolution of Darwin

404132862 — Fri, 13 Feb 2009 15:57:05 -0500

In a fitting celebration of a man whose ideas revolutionized science, Harvard marked Charles Darwin’s 200th birthday in style yesterday.

There was a campuswide read-a-thon of “The Origin of Species,” a roving gorilla, three bushy-bearded Darwin imitators, an afternoon symposium, and a nighttime birthday blast at the Cambridge Queen’s Head Pub rocked by science-themed bands.

Exploring hidden life’s abundance

404132862 — Wed, 11 Feb 2009 15:55:25 -0500

Two miles below the surface of the Sargasso Sea lies a depression in the Earth’s crust filled with sediment and, scientists believe, teeming with life — exotic, microscopic, and very likely never before seen by human eyes.

Global warming changing Walden Pond

404132862 — Wed, 29 Oct 2008 10:58:24 -0400

Records dating back to Thoreau show some sharp shifts in plant flowering near Walden Pond

404132862 — Tue, 28 Oct 2008 12:25:55 -0400

Drawing on records dating back to the journals of Henry David Thoreau, scientists at Harvard University have found that different plant families near Walden Pond in Concord, Mass., have borne the effects of climate change in strikingly different ways. Some of the plant families hit hardest by global warming have included beloved species like lilies, orchids, violets, roses, and dogwoods.

Seeing what they hear, to better understand ourselves

404132862 — Wed, 24 Sep 2008 16:09:26 -0400

It was a long drive from St. Louis to Florida, but Darlene Ketten had finally made it. Standing in the warm surf of St. George Island, she watched with delight as tiny, colorful bean clams popped out of the sand and then quickly reburied themselves as the waves foamed around her calves.

“It was gorgeous, with incredible soft, white sand,” Ketten recalled. “In the surf were minute clams — pink, blue, orange and gold — popping out of the sand and then disappearing…. I dipped my hand in the water and tasted it.”

Boning up on frogs' defenses

404132862 — Tue, 24 Jun 2008 14:13:51 -0400

Harvard biologists have determined that some African frogs carry concealed weapons: when threatened, these species puncture their own skin with sharp bones in their toes, using the bones as claws capable of wounding predators.

The unusual defense mechanism is described by Harvard's David C. Blackburn, James Hanken, and Farish A. Jenkins, Jr., in a forthcoming issue of the journal Biology Letters.

Mars' water appears to have been too salty to support life

yvette — Wed, 28 May 2008 13:10:42 -0400

A new analysis of the Martian rock that gave hints of water on the Red Planet -- and, therefore, optimism about the prospect of life -- now suggests the water was more likely a thick brine, far too salty to support life as we know it.

The finding, by scientists at Harvard University and Stony Brook University, is detailed this week in the journal Science.