The "Human Being" - A Search for Ultimate Causation

Introduction: What is a 'Human'?

What do we mean by the label 'human'? Is a human a physical manifestation, a skeletal type, a species, or something else? Donald Johanson (1982:100), describing the classification of Homo habilis discovered by the Leaky team at Olduvai in 1964, wrote:

Although most anthropologists and paleoanthropologists seem to define a human by the physical characteristics of skeletal structure, I feel that a human cannot be rigidly defined using these attributes. The human being, from my point of view, is a state of being, a state of consciousness. Kenneth P. Oakly (1968:3), in his book, Man the Tool Maker, cites Sir Wilfred Le Gros Clark as commenting:

Evolutionarily speaking, this makes it impossible to categorize a fossil as human, or not human, since there is no direct method to determine the organism's mental capacity or state of consciousness. As a result, scientists concentrate their efforts of definition to the concrete, measurable, and available artifacts periodically surfaced from the beds of history.

Even so, their definitions of 'human' can never be complete without a knowledge of the animal's capacity for information processing, self awareness, and ingenuity, for we are the species that generally feels itself as unique and somehow apart from the rest of nature by this dubious quality of our intellect.

This presents a problem, in that if a definition, as extended by Le Gros Clark, is based strictly on a mental capacity, or what I call a state of being, there must exist some limit to what we call human. A problem because, there exist, many of our kind that may not exceed that level of discrimination for a variety of physiological reasons. To say that they should not be classed as 'humans' is almost unthinkable.

Then why do we try to define some thing as 'human'? The fact is our kind does exist, we are a species by definition, and we are searching for our origins for a number of reasons. We are asking the questions 'what happened to make us mankind?' 'when did we arise?', and 'how did we get here?'. In attempting to answer these questions, the objective has to be viewed as a pin-pointing of the beginning of the genus Homo. This leads to the definition of the various species of Homo, and the subsequent question of the origins of man, the Human Being. Is Homo sapiens , habilis, erectus, or some other species of animal the beginning of the human state of consciousness?

This approach also presents another problem identified by Johanson, in discussing the definition of species. The definition includes the characteristic of genetic isolation (not being able to produce fertile offspring). He goes on to say that species can be isolated both horizontally (physically, such as by geography, or behaviorally, such as by non-recognition of another as suitable partners), and vertically by way of time:

If we subscribe to the theory of evolution, we must at some point between the first living cells of the Precambrian and creatures such as the one we called Albert Einstein, create species dividing lines, or at least grey fuzzy divisional areas, that allow distinction. Presently, anatomists use the concept of significant differences in skeletal structure to segregate species.

I feel that this method of distinction is limited in that the separations are too gross: too gross because from one day to the next, or one year to the next, we cannot say that a dividing line exists between individuals from the physiological perspective. If we consider Joahanson's statements above, vertical isolation can only be identified in large gaps of time, after which physiological changes have occurred.

1. Behavior as an Ultimate Cause for Natural Selection.

I believe that physiological characteristics are a result of natural selection based on what behaviors animals exhibit, a view noted by Fedigan (1982:32). The chicken and egg question of environment vs. behavior does not logically exist for me. Life is obviously environment-based, but once initiated, life continues to actively survive only by constantly behaving in the environment. When an organism stops behaving, the biological machine eventually dies, either from starvation, or predation. The environment does not prod or prompt; it is stable, or it kills. Behavior in the individual allows an organism to live. My understanding can best be explained by the following paragraphs.

A. An Example of Natural Selection Through Behavior.

I see the selection of larger canines ultimately going back to the generalized dental structure of early primates, to a point where there was relatively no difference in size between canines and other teeth. Selection for larger canines began when the organism which was ancestor to the baboon took a behavior trait from its repertoire of eating behaviors and used as a method for defense (biting). It could be argued that the environmental pressure was not defense, but that it was a change in the food type which required larger canines. Since baboons do not have a diet that depends on use of large canines, I feel that this type of pressure was not important enough to cause the adaptive advantage necessary for selection in its ancestors.

On the other hand, if predation was an every day concern of the baboon ancestor (and other early primates also), then having a set of impressive canines (both in effect and visually), would lead to an advantage for survival, in both a defensive and social sense.

Once the behavior was put in use, the enlargement of canines would be fairly rapid, as long as predation was a factor in survival. At that point in time, and only then, could descendants exhibit subsequent behaviors which would allow for modifying defensive biting behaviors towards less destructive group behaviors such as threat displays, or behaviors which allow the opportunity to take advantage of different food sources, thus explaining the predominance of canines in various forms of primates.

In the case of baboons, I feel the subsequent use of canines as a inter-group display mechanism would play a strong part in male-male competitions, selecting for limited threat behavior rather than unlimited destruction of individuals through fights to the death. The effectiveness of the display would depend on the relative size of the teeth, and as such, bigger would be better. Thus canine growth would continue until limited by disadvantageous size of the jaw structures.

If we look at human canines, we find that they are not large at all, therefore indicating that the human lineage broke off from the baboon lineage prior to the use of canines as a defense strategy. Others may counter that the canines could have reduced in size due to the fact that they were not required by our lineage, but I find it difficult to find a environmental pressure that would require the exhibition of behaviors that would allow such a selection for smaller canines. I also feel the argument that the phenotype with more generalized dental structures was allowed to exist, and therefore lead to a reduction, to be questionable. What we would see in that case, is what we see in the case of the great apes; a stabilization of the dental structure at a level within the range of variability for canines which have previously been selected for size.

The key point in this canine size argument is that behavior had to be exhibited to allow the natural selection of physical characteristics.

B. What do Anatomical Differences Mean?

C. Information Processing as the Criterion for Classification.

In summary then, I believe behavior, in response to the environment, to be the first act in the process of natural selection.

2. Separating the Human from Primates.

A. Anatomy

B. Behavior

These similarities, I suggest are the set of surviving qualities of the common ancestor stock from which all evolved. The differences would indicate the various branches along the evolutionary path from the common ancestor to the present day species.

In combination with the existing physiological comparison data such as immunological distance comparisons, we then could validate the age of certain behavior patterns. For example, a behavior pattern common between Chimpanzees, Gorillas, and Man would have existed prior to the split of the lineages making up the three species. A behavior common to the gorilla and chimpanzee, but unique to man would indicate a behavior that was exhibited and selected for in the case of man versus the environment during his unique evolutionary development.

What then can we segregate from primate behaviors as common, and what can we say is unique to each species? Comparisons of species behaviors at a general level indicate that primate species are pretty much the same as one another. In most cases, all care for the young, the young have relatively longer infant dependency periods than other mammals, play is a significant factor in development, and social learning is a major factor in the development of healthy individuals.

C. Intellect

(c) 1986, 1999. Lark Ritchie. All Rights Reserved. Contact me at this address..