From: "David Blair" 

Just caught this. I'll go take a look.


I'm having to use dialup for a few weeks, so I won't be here much for a
while. This really BITES, by the way. I've gotten too used to broadband....



"David N. Barnett"  wrote in message
news:57fh409uv1i40v2am8j91n28qmtdpjrv28{at}4ax.com...
> Looks like Tim White and his Ardipithecus is starting to surface,
> finally.
>
> http://story.news.yahoo.com/news?
> tmpl=story&u=/nm/20040304/sc_nm/science_human_dc
>
> Early Human Ancestor Had Small Teeth
> Thu Mar 4, 2:02 PM ET
>
> By Maggie Fox, Health and Science Correspondent
>
> WASHINGTON (Reuters) - A 6 million-year-old creature that lacked sharp
> canines for fighting may be the first pre-human to have branched off
> from the ape line, researchers said on Thursday.
>
> The short, small-brained creature may provide a good hint of what the
> common ancestor of chimpanzees and humans looked like, the researchers
> said.
>
> Fossil remains of the early hominid were found in Ethiopia three years
> ago, and it seemed to be a subspecies of a known pre-human,
> Ardipithecus ramidus.
>
> But the scientists have found more teeth from a group of the hominid,
> re-classified it as a distinct species and named it Ardipithecus
> kadabba.
>
> "Ardipithecus kadabba may also represent the first species on the
> human branch of the family tree just after the evolutionary split
> between lines leading to modern chimpanzees and humans," said Yohannes
> Haile-Selassie, curator and head of physical anthropology at the
> Cleveland Museum of Natural History in Ohio, who led the study.
>
> His team's report, published in Friday's issue of the journal Science,
> suggests that the last common ancestor of chimps and humans had long
> canines used to fight -- something chimps have today, but not humans.
>
> The researchers dug up fossils from at least five individuals who once
> lived in a wooded environment, now a dry, rocky area in the Afar rift
> of Ethiopia's Middle Awash region -- a rich source of pre-human
> remains.
>
> They had enough to determine that it was an upright-standing hominid
> about the size of a chimpanzee that lived between 5.2 and 5.8 million
> years ago.
>
> Six new teeth were found at the site in 2002 and included an upper
> canine, premolars from both jaws, and upper molars.
>
> "We see a lot of primitiveness in the teeth," Haile-Selaisse said in a
> telephone interview.
>
> One key characteristic is a self-sharpening function.
>
> "The canine tooth comes across the outside face of the lower premolar
> and it sharpens that way," said Tim White of the University of
> California Berkeley, who worked on the report.
>
> "It is like honing a knife on a stone. Almost all of the monkeys and
> all of the apes, they have all very long and projecting canines (with
> this mechanism)."
>
> In modern apes these sharp teeth are used by males for fighting, or to
> frighten off an aggressor. The theory is that hominids evolved more
> peaceable behavior, said White, with females choosing males who could
> stand upright and help raise young over males who were busy fighting
> and showing off.
>
> Fossil remains of similar creatures found in Chad and Kenya are
> similar enough to suggest they are closely related -- even in the same
> genus as Ardipithecus, the researchers said.
>
> "We now have an assemblage or set of early canines and none of them
> are big and slashing," White said.
>
> "What this indicates is that earliest hominids had these small canines
> that were in the same animal as a small brain -- we know that from
> skull in Chad -- and that head was attached to a bipedal body."
>
> One of the most famous pre-humans, "Lucy" or Australopithecus
> afarensis, dates back 3 million years. "This doubles the time period
> all the way back to 6 million years that a small-brained, small-canine
> bipedal early hominid existed," White said.
>
> Genetics tells scientists that chimpanzees and hominids diverged from
> a common ancestor around 7 million years ago. "But genetics can't tell
> us what this animal was like," White said.
>
> It is also becoming clear that looking at chimpanzees, who evolved as
> much as humans did if not more over this period, do not provide a good
> model of the ancestor, either.
>

--- BBBS/NT v4.01 Flag-5