Not until the advent of Homo erectus, the species immediately ancestral to Homo sapiens, is there evidence of the omnivorous diet that is typical of human beings today.
If confirmed, the findings would upset several widely held assumptions about the diet of early hominids, or human-like creatures. It is generally held, for example, that the large, flat-topped molars of the robust forms of Australopithecus were used to grind tough nuts and roots. The smaller form of Australopithecus and a similarly gracile form of true human being called Homo habilis were thought to have been omnivorous, mixing meat with roots, nuts, eggs, shoots and fruit.
"I don't want to make too much of this yet", said Dr. Alan Walker, a Johns Hopkins University anthropologist, who discovered the dental evidence. "But it is quite a surprise."
No Exceptions Found
The sample of teeth
studied so far is small fewer than two dozen representing four
major types of hominids. But, while the sample is small, no exceptions
have been found.
The findings are based on extremely detailed analysis of the microscopic wear patterns on the chewing surfaces of the teeth. The method, which Dr. Walker invented, uses a scanning electronic microscope to see scratches and pits that are invisible to the naked eye.
Dr. Walker has found that different kinds of food contain materials that mar the enamel surface of a tooth in characteristic ways. It is possible even to distinguish between a grass-eater and a leaf-eater because each food contains characteristic types and quantities of silica crystals that form naturally within plant cells. These crystals, called phytoliths, are harder than tooth enamel and scratch it slightly as the animal chews its food.
Grasses contain a much higher proportion of phytoliths than do leaves of bushes and trees. Fruits contain almost none at all. As a result, fruit eaters' teeth are highly polished, lacking any of the wear patterns characteristic of other food sources. Meats contain no phytoliths but the teeth of carnivores show scratches caused by crunching into bone.
Consistent Patterns of Wear
Using the teeth of various living mammals whose diets are known, Dr. Walker has established that the basic pattern of microwear on teeth is fairly consistent from one species to another. This is largely because tooth enamel is essentially the same substance throughout the animal kingdom.
To prove his method, Dr. Walker has compared the microwear patterns on closely related species of animals that are known to have different feeding habits. For example, of two closely related species of hyrax (rodent-sized hooved mammals sometimes called conies), one feeds predominantly on grass while the other is a browser, eating leaves of bushes and trees. Their teeth can be told apart easily using a scanning electronic microscope.
Dr. Walker has established similar patterns in the various types of wild pig, such as warthog, and among a number of monkeys and apes. It is against these patterns that the hominid teeth are checked.
If it is true that the earliest hominids were all predominantly fruit eaters, the fact would suggest a way of life more like that of chimpanzees living in forests than most anthropologists had suspected.
Note: DNA-wise, humans more closely resemble the Bonobo than they do the Chimpanzee, and the differences between these two primates are striking, including walking gait (Bonobos walk upright far more often than Chimps), social behavior (Chimps are more aggressive than Bonobos), and dietary preferences (Bonobos eat more fruit than Chimps).
And regarding the conflicting information that has been circulated since the above information first appeared, please keep this in mind: Humans are the only animal that can come up with evidence to support a closely held belief which, in reality, is untrue. Some people who have a vested interest in perpetuating the "we're meant to eat meat" information, and those who simply prefer to believe that this is the case, go to great lengths to discredit honest information and to give credibility to their point of view, sacrificing honesty and accuracy for personal preference and profit motives. It is unfortunate that these campaigns do nothing more than confuse the issue and make it difficult for some people to get at the truth.
So, yes, we were
at one time "hunter/gatherers", and many people refer to this
behavior as if this is the way it had always been. But we were foragers
before we were hunter/gatherers, just like our closest primate cousins.
We didn't need tools to eat, and we didn't need to chase or trap our food,
it just sat there waiting for us to grab it, and we were in good enough
shape to be able to climb to get some of it. Today about the only thing
some of us are capable of climbing is the corporate ladder; to climb even
a flight of stairs would sideline some people. To be as healthy as you
are capable of being, you need to heed the Natural Laws that pertain to
health (even though they may call into question some long-standing beliefs).