Wayne Wynn wrote regarding Robert W. Sussman's "Man the Hunted: Primates,
Predators and Human Evolution":
> Excerpt from 
> http://www.eurekalert.org/pub_releases/2005-02/wuis-th020305.php:
> 
>     'Man the Hunter' theory is debunked in new book\
>     ...
> 
>     But what Sussman and Hart discovered is that Australopithecus
>     afarensis was not dentally pre-adapted to eat meat. "It 
> didn't have
>     the sharp shearing blades necessary to retain and cut such foods,"
>     Sussman says. "These early humans simply couldn't eat 
> meat. If they
>     couldn't eat meat, why would they hunt?"
> 
> 
> A major point is that humans are not primarily meat-eaters by 
> evolution. 
> It appears to be putting a lot of inference on one ancestor who lived 
> between 5 and 3.5 million years ago.
> 
> Anyone have more informed knowledge about this?

While the "Man the Hunter" model is indeed very much in debate, there seems
to be a fairly wide consensus that Australopithecines likely ate some
non-plant foods. The ancestor of all primates, an animal that resembled
today's tree shrew, is believed (like the tree shrew) to have dined entirely
on insects and other small animal foods. Though the first species that
descendended from this ancestral primate diverged into mainly frugivorous
and herbivorous diets, many primate species then returned to eating more and
more animal foods as their habitats changed over the millenia (apparently as
an adaptation to changing climate), with the most recent primates (such as H
neanderthalensis, H sapiens idaltu and H sapiens sapiens) eating the most
meat of all primates. Australopithecines are widely acknowledged to have
included some meat in their diet, with the main point of contention being
whether they scavenged or hunted most of it. Through Jane Goodall's research
we have learned that even chimpanzees hunt and eat meat, making it hard to
believe that Australopithecines did not hunt at least some of their meat.

The Australopithecines apparently "ate a large number of small animals and
were scavengers; they ate the remains of any large animals they could find,
and therefore were able to secure a large amount of meat." (H. Leon Abrams,
Jr., MA, EDS, Associate Professor Emeritus of Anthropology, sourcing
Schaller, George B and Gordon Lowther, "The Relevance of Carnivore Behavior
to the Study of Early Hominids," Southwest J Anthro, 25:307-41, 1969.) 

According to an article in New Scientist (Human Origins: The Challenge of
the Java Skulls, 7/5/94), Homo Erectus is "clearly a different kind of
animal from earlier hominid species", being "much more human in stature and
build ...and, judging from the structure of its teeth and the content of
associated archaeology sites, it apparently included significant amounts of
meat in it's diet." [The Diet of Early Humans: What did our ancestors eat?
International Vegetarian Union,
http://www.ivu.org/history/early/ancestors.html] Since homo erectus, who
predates modern humans, ate "significant amounts of meat," why would anyone
assume that humans are not designed to do so?

Even some respected advocates of vegetarianism admit that humans and their
pre-human ancestors have eaten meat for millions of years. In a talk given
by the vegetarian Dr David Ryde to a Symposium organised by The Vegetarian
Society in 1986, he stated, "since 4.5 million years ago our ancestral
feeding pattern included increasing amounts of meat." [Ibid]

Even Robert Sussman and nutrition researcher T. Colin Campbell do not
advocate humans eating a completely vegetarian diet. They acknowledge that
humans are designed to eat SOME animal foods.


Excerpts from 
Our Closest Relatives: Jane Goodall's Wild Chimpanzees
http://www.pbs.org/wnet/nature/goodall/relatives.html--

> While we may believe that we have nothing but ancestors in common with our
primate relatives, Jane Goodall's research into chimpanzee behavior shows
that, in areas from warfare to parenting, our two species are closely
linked. For example, she found that, like us, chimpanzees create tools to
make their lives easier -- such as the carefully chosen grass stems used to
"fish" for tasty insects, as shown in this NATURE program. 

> Goodall followed up this discovery with stunning evidence that the
seemingly peaceful chimpanzees in fact systematically hunted smaller
primates, such as colobus monkeys, for meat: one such hunt is grippingly
documented on NATURE. 

> Most dramatically, her work shattered two long-standing myths: the idea
that only humans could make and use tools, and the belief that chimps were
passive vegetarians. 

> Goodall's Gombe data have also led researchers to take a closer look at
the role that hunting plays in chimp feeding habits. One recent Gombe study,
for instance, concluded that the 45 members of one troop ate a ton of monkey
meat per year. During one hunting binge, chimps killed 71 colobus monkeys in
68 days; one chimp alone killed 42 monkeys over five years. All told, chimps
may kill and eat a third of the Gombe's colobus population each year.
Researchers have also found that lower-ranking males often trade the meat
for mating privileges; such trades may help prevent inbreeding by keeping a
single group of males from fathering the majority of a troop's children.


Excerpt from
Chimpanzee Hunting Behavior and Human Evolution 
Chimpanzees are efficient predators that use meat as a political and
reproductive tool. Are there implications for the evolution of human
behavior? 
Craig B. Stanford
This article originally appeared in the May-June 1995 issue of American
Scientist. 
 
http://www.americanscientist.org/template/AssetDetail/assetid/24543?fulltext
=true

> In the early 1960s, when the british primatologist Jane Goodall first
observed wild chimpanzees hunting and eating meat in Gombe National Park,
Tanzania, it was widely believed that these animals were strict vegetarians.
Skeptics suggested that the diet of the Gombe chimpanzees was aberrant.
Others suggested that the quantity of meat the chimpanzees ate was trivial.
After more than 30 years of research, however, it is now clear that meat is
a natural part of the chimpanzees' diet. Indeed, hunting has been observed
at most of the other sites where chimpanzees are studied across central
Africa. And, it turns out, a chimpanzee community may eat several hundred
kilograms of meat in a single year.