IPTEK For Life: 2012

Giant Prehistoric Penguins Revealed: Big but Skinny

20.34

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For decades, study co-author Ewan Fordyce, a paleontologist at New Zealand's University of Otago, had been happening across bones of the species while searching for fossil whales and dolphins.

Only recently, though, has a team reconstructed a full skeleton. This composite—created using a model of a modern-day king penguin—represents both species, which were quite similar.

The result is "quite a streamlined animal—it wouldn't look like any penguin that's alive today," said study leader Dan Ksepka, an avian paleontologist at North Carolina State University.

Instead of a modern penguin's rotund shape, each of the newly named species had a narrow chest; long, tapering flippers; and a narrow beak—a body specialized for hunting fish.

Standing about 4.3 feet (1.3 meters) tall, both species would have been taller than the tallest living penguin species, the emperor penguin, which can reach 4 feet (1.2 meters) tall.

Prehistoric New Zealand

In the penguins' time, New Zealand itself was mostly underwater—only a smattering of islets were above the surface. Shallow waves rich with food and protection from predators would've made the habitat ideal for the birds.

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32,000-Year-Old Plant Brought Back to Life—Oldest Yet

06.20

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A Russian team discovered a seed cache of Silene stenophylla, a flowering plant native to Siberia, that had been buried by an Ice Age squirrel near the banks of the Kolyma River (map). Radiocarbon dating confirmed that the seeds were 32,000 years old.

The mature and immature seeds, which had been entirely encased in ice, were unearthed from 124 feet (38 meters) below the permafrost, surrounded by layers that included mammoth, bison, and woolly rhinoceros bones.

The mature seeds had been damaged—perhaps by the squirrel itself, to prevent them from germinating in the burrow. But some of the immature seeds retained viable plant material.

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Earth Spun Faster in 2009 Due to Ocean Current?

04.45

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Did it feel like time flew in November 2009? It turns out the days were actually going a wee bit faster for part of that month, according to a team of NASA and European scientists.
Earth spun about 0.1 millisecond faster for a two-week stretch, said study co-author Steven Marcus, a researcher at NASA's Jet Propulsion Laboratory in Pasadena, California.

The planet's speedier spin appears to have been due to a slowdown in an ocean current that whips around Antarctica.
(Related: "Japan's Earthquake Shortened Days, Increased Wobble.")
"The Earth speeding up is just like a [twirling ice] skater pulling in her arms," he explained. When the skater does this, she spins faster, because the laws of physics dictate that her body must conserve what's called angular momentum.
"When [the skater] sticks out her arms, they move pretty fast, because there's a big circle. When she pulls in her arms, the circle is smaller, so in order to have the same angular momentum, she has to speed up," Marcus said.
"It is the same with the Earth," in the sense that if an ocean current slows down, the planet's spin must speed up to conserve angular momentum.
Scientists have long known that changes in the speed of ocean and atmospheric currents can—and do—slightly affect the rate of Earth's rotation and, hence, the length of a day.
"The thing is, with the ocean the effect is a lot weaker, since the ocean flows a lot slower than the atmosphere," Marcus said.

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New Ultradense Planet Found; Astronomers Baffled

04.38

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Dubbed CoRoT-20b, the planet is thought to be a gas giant about four-fifths the size of Jupiter and orbits close to a sunlike star.

Despite the new planet's relatively diminutive size, this world has four times Jupiter's mass, making CoRoT-20b one of the densest known planets, a new study says.

That poses a problem for astronomers: If CoRoT-20b is structured like a traditional gas giant, with a solid core surrounded by a gassy atmosphere, the planet's core would have to make up 50 to 77 percent of the world's total mass.

By contrast, Jupiter's core is thought to represent just 15 percent of that planet's mass.

To have such a robust core, CoRoT-20b would defy current theories for how planets form.

Astronomers think planets are born from disks of debris that surround newborn stars. In our solar system, the sun's so-called protoplanetary disk gave rise to several worlds and still had leftovers from planet formation—what we callasteroids and comets.

However, the new study says that CoRoT-20b would have had to have sucked up every last atom of material heavier than helium from its star's protoplanetary disk to form the planet's massive core.

"That is something difficult to understand, and to admit," said study leader Magali Deleuil, of the Laboratory of Astrophysics of Marseilles in France.

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