2.5 Million Year Habit

[Guest guest]

 Meat eating is an old human habit

 

http://www.newscientist.com/news/news.jsp?id=ns99994122

 

 

10:00 07 September 03

 

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Humans evolved beyond their vegetarian roots and became meat-eaters at the

dawn of the genus Homo, around 2.5 million years ago, according to a study

of our ancestors' teeth.

 

In 1999, researchers found cut marks on animal bones dated at around 2.5

million years old. But no one could be sure that they were made by

meat-eating hominids, because none appeared to have suitable teeth.

 

Now an analysis by Peter Ungar of the University of Arkansas has revealed

that the first members of Homo had much sharper teeth than their most

likely immediate ancestor, Australopithecus afarensis, the species that

produced the famous fossil Lucy.

 

What sharp teeth you have...

 

Eating meat requires teeth adapted more to cutting than to grinding. The

ability to cut is determined by the slope of the cusps, or crests.

" Steeper crests mean the ability to consume tougher foods, " Ungar says. He

has found that the crests of teeth from early Homo skeletons are steeper

than those of gorillas, which consume foods as tough as leaves and stems,

but not meat.

 

But the crests of teeth from A. afarensis are not only shallower than

those of early Homo, they are also shallower than those of chimpanzees,

which consume mostly soft foods such as ripe fruit, and almost no meat.

 

" Ungar shows that early Homo had teeth adapted to tougher food than A.

afarensis or [chimpanzees]. The obvious candidate is meat, " says

anthropologist Richard Wrangham of Harvard University.

 

Ungar used a laser to scan each tooth and mapped the surface as though it

were a landscape, using a geographic information system, he told a

symposium on diet and evolution at the University of Arkansas in August.

 

He had to find a way to compare teeth already worn by use, because unworn

teeth are extremely rare in fossils. In a previous study on the teeth of

gorillas and chimps, he validated the technique by showing that the

differences between species' teeth remain constant however much they are

worn down (Proceedings of the National Academy of Sciences, vol 100, p

3874).

 

 

David Holzman

 

 

 

 

 

We live in a world which is full of misery and ignorance, and the

plain duty of each and all of us is to try to make the little corner he can

influence somewhat less miserable and somewhat less ignorant than it was

before he entered it.

- Thomas Henry Huxley (1825-1895)

[Guest guest]

>  Meat eating is an old human habit

 

Time we kicked it, then, if we haven't already, especially if we want to

live to be old humans. And it falls (a letter) short of being humane.

 

Best,

Pat

--

SANTBROWN

townhounds/

http://www.angelfire.com/art/pendragon/

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* " I will not let anyone walk through my mind with their dirty feet " - Gandhi

 

* " But for the sake of some little mouthful of flesh, we deprive a soul

of the sun and light, and of that proportion of life and time it had

been born into the world to enjoy. " - Plutarch

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