Friday, February 27, 2009

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World's Oldest Prehistoric Axes Unearthed By JULIA ZAPPEI, AP
posted: 28 DAYS 8 HOURS AGOcomments: 555filed under: World NewsPrintShareText SizeAAAKUALA LUMPUR, Malaysia (Jan. 30) - Malaysian archeologists have unearthed prehistoric stone axes that they said Friday were the world's oldest at about 1.8 million years old.
Seven axes were found with other tools at an excavation site in Malaysia's northern Perak state in June, and tests by a Tokyo laboratory indicate they were about 1.83 million years old, said Mokhtar Saidin, director of the Center for Archaeological Research at the University of Science Malaysia.
The group released their conclusions Thursday, and other archeologists have not yet examined the results.
"It's really the first time we have such evidence (dating back) 1.83 million years," Mokhtar said, adding that the oldest axes previously discovered were 1.6 million years old in Africa.
However, other chopping tools, as well as human remains, have been found in Africa that are much older, with some dating back 4 million years, he said.
Geochronology Japan Inc., a lab in Tokyo, calculated the age of the tools by analyzing the rock that covered them, Mokhtar said. The result has a margin of error of 610,000 years, he said.
Some previous discoveries have suggested there were humans in Southeast Asia up to 1.9 million years ago, but those have been disputed, said Harry Truman Simanjuntak, a researcher at the National Research Center of Archaeology in Jakarta.
Simanjuntak cautioned that others still need to investigate claims about the axes' age.
The oldest previous evidence of human existence in Malaysia was stone tools dating back about 200,000 years, found at the same excavation site in Perak.
The archeologists are trying to find human bone remains in Perak, Mokhtar said, but stressed that it might be unlikely because of decay due to warm, humid climate conditions. The oldest bones found in Perak so far have only been about 10,000 years old.
Copyright 2009 The Associated Press. The information contained in the AP news report may not be published, broadcast, rewritten or otherwise distributed without the prior written authority of The Associated Press. Active hyperlinks have been inserted by AOL.
2009-01-30 07:47:52

Ancient Whales Gave Birth on Land By Jeanna Bryner, Senior Writer, LiveScience
posted: 22 DAYS 18 HOURS AGOcomments: 584filed under: Science NewsPrintShareText SizeAAASkip over this content

(Feb. 4) -- More than 47 million years ago, a whale was about to give birth to her young ... on land. That's according to skeletal remains of a pregnant cetacean whose fetus was positioned head-down as is the case for land mammals but not aquatic whales.
The teeth of the fetus were so well-developed that researchers who analyzed the fossils think the baby would have been born within days, had its mom not died.
The fossil discovery marks the first extinct whale and fetus combination known to date, shedding light on the lifestyle of ancient whales as they made the transition from land to sea during the Eocene Epoch (between 54.8 million and 33.7 million years ago).
Philip Gingerich, a paleontologist at the University of Michigan, Ann Arbor, and his team discovered the pregnant whale remains in Pakistan in 2000, and then in 2004, Gingerich's co-authors and others found the nearly complete skeleton of an adult male from the same species in those fossil beds. The adult whales are each about 8.5 feet long and weighed between 615 and 860 pounds, though the male was slightly longer and heavier than the female.
(Gingerich is also director of the University of Michigan's Museum of Paleontology.)
On the dig that ultimately yielded the pregnant whale, Gingerich and his team first spotted what looked like a line of chalk on the ground surface, which later turned out to be the teeth of the whale fetus.
"Very quickly I got into the baby's teeth," Gingerich told LiveScience. "Then I kept going around it, and the ribs seemed too big for the size of the animal and they were all going the wrong way. So I have to say I spent the whole day excavating this thing confused about what in the world was going on here."
Soon after, Gingeric discovered another, larger, skull, and he realized the fetus was still inside its mother.The new species, now called Maiacetus inuus, is a member of the Archaeoceti, a group of cetaceans (an animal group that includes whales, dolphins and porpoises) that predate modern toothed and baleen whales. Archaeocetes had mouths full of several types of teeth, as well as nostrils near the nose tip. Both features are seen in land mammals but not in today's whales.
Like other archaeocetes, the newly discovered whale was equipped with four legs modified for foot-powered swimming (sort of like climbing, or scrambling, up a steep hill but instead in water). While the whales likely could support their weight on their flipper-like limbs, they probably couldn't go far on land.
"They clearly were tied to the shore," Gingerich said. "They were living at the land-sea interface and going back and forth."
The team suggests that Maiacetus fed at sea and came ashore to rest, mate and give birth.
The head-first position of the fetus matches what is found in many land animals, particularly the artiodactyls (pigs, deer and cows), which are thought to have given rise to ancient whales. Human babies also emerge head first, ideally.
Scientists speculate that a head-first orientation allows land mammals to breathe even if they get stuck in the birth canal.
That's not the case underwater. "If you're born in the water you don't want the head out away from the mother until it's going to pop free, because you don't want it to drown,” Gingerich said.
In addition, tail-first delivery in modern whales and dolphins would ensure the baby is facing in the same direction as its mother who is likely swimming. To keep mom and baby from getting separated, tail-first delivery would be optimal, Gingerich said.
The research, published in the Feb. 4 issue of the online journal PloS ONE, was funded by the Geological Survey of Pakistan, National Geographic Society, National Science Foundation and Alexander von Humboldt Foundation. © Imaginova Corp. All rights reserved.
2009-02-04 12:52:41

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