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Observatory: DNA Shifts Timeline for Mammoths’ Exit
By HENRY FOUNTAIN, The New York Times, December 22, 2009
Thousands of years ago in northwestern North America, large animal species, among them the woolly mammoth and the horse, became extinct. Among the proposed explanations for this is one known as the blitzkrieg hypothesis — that humans entering the region rapidly wiped the animals out through overhunting.
The validity of that explanation, and others, depends in parts on the timing of the extinctions. How many thousands of years ago did the animals disappear?
Until now, the answer to that question has been 13,000 to 15,000 years ago. But those dates come from the youngest reliably dated fossils that have been found, and who is to say there aren’t even younger fossils out there?
A new study has come up with a far different answer, using a far different technique.
Rather than dating actual fossils, the researchers analyzed DNA found in permanently frozen sediments at a site on the Yukon River in central Alaska. As they report in The Proceedings of the National Academy of Sciences, they found evidence that mammoths and horses were still around at least until 10,500 years ago, long after humans arrived.
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Observatory: Foraging Early Humans Did Not Pass Up Grains
By HENRY FOUNTAIN, The New York Times, December 22, 2009
Early humans were hunter-gatherers, but what did they gather? The easy stuff, archeologists say — roots, fruits and nuts. Until relatively late in the Pleistocene, which ended about 12,000 years ago, grains were thought to have been largely ignored by foraging humans, at least in part because they were difficult to process.
But Julio Mercader, an archeologist at the University of Calgary, has now found evidence from a cave in Mozambique that humans were eating sorghum grasses at least 105,000 years ago. The evidence was in the form of microscopic starch granules found on stone tools from the cave.
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Basics: Sorry, Vegans: Brussels Sprouts Like to Live, Too
By NATALIE ANGIER, The New York Times, December 22, 2009
I stopped eating pork about eight years ago, after a scientist happened to mention that the animal whose teeth most closely resemble our own is the pig. Unable to shake the image of a perky little pig flashing me a brilliant George Clooney smile, I decided it was easier to forgo the Christmas ham. A couple of years later, I gave up on all mammalian meat, period. I still eat fish and poultry, however and pour eggnog in my coffee. My dietary decisions are arbitrary and inconsistent, and when friends ask why I’m willing to try the duck but not the lamb, I don’t have a good answer. Food choices are often like that: difficult to articulate yet strongly held. And lately, debates over food choices have flared with particular vehemence.
( Read More )
By HENRY FOUNTAIN, The New York Times, December 22, 2009
Thousands of years ago in northwestern North America, large animal species, among them the woolly mammoth and the horse, became extinct. Among the proposed explanations for this is one known as the blitzkrieg hypothesis — that humans entering the region rapidly wiped the animals out through overhunting.
The validity of that explanation, and others, depends in parts on the timing of the extinctions. How many thousands of years ago did the animals disappear?
Until now, the answer to that question has been 13,000 to 15,000 years ago. But those dates come from the youngest reliably dated fossils that have been found, and who is to say there aren’t even younger fossils out there?
A new study has come up with a far different answer, using a far different technique.
Rather than dating actual fossils, the researchers analyzed DNA found in permanently frozen sediments at a site on the Yukon River in central Alaska. As they report in The Proceedings of the National Academy of Sciences, they found evidence that mammoths and horses were still around at least until 10,500 years ago, long after humans arrived.
( Read More )
Observatory: Foraging Early Humans Did Not Pass Up Grains
By HENRY FOUNTAIN, The New York Times, December 22, 2009
Early humans were hunter-gatherers, but what did they gather? The easy stuff, archeologists say — roots, fruits and nuts. Until relatively late in the Pleistocene, which ended about 12,000 years ago, grains were thought to have been largely ignored by foraging humans, at least in part because they were difficult to process.
But Julio Mercader, an archeologist at the University of Calgary, has now found evidence from a cave in Mozambique that humans were eating sorghum grasses at least 105,000 years ago. The evidence was in the form of microscopic starch granules found on stone tools from the cave.
( Read More )
Basics: Sorry, Vegans: Brussels Sprouts Like to Live, Too
By NATALIE ANGIER, The New York Times, December 22, 2009
I stopped eating pork about eight years ago, after a scientist happened to mention that the animal whose teeth most closely resemble our own is the pig. Unable to shake the image of a perky little pig flashing me a brilliant George Clooney smile, I decided it was easier to forgo the Christmas ham. A couple of years later, I gave up on all mammalian meat, period. I still eat fish and poultry, however and pour eggnog in my coffee. My dietary decisions are arbitrary and inconsistent, and when friends ask why I’m willing to try the duck but not the lamb, I don’t have a good answer. Food choices are often like that: difficult to articulate yet strongly held. And lately, debates over food choices have flared with particular vehemence.
( Read More )
