Heroes

Our species is nothing if not vain. The natural world is saturated with wonders, yet the phenomena of most concern are those directly relating to us. Even in the long public argument over evolution, where the ancestry of whales and birds is often quarreled over, our own ancestry is the real reason for the contention. What makes evolution so threatening to some is that it applies to every organism and does not allow us to draw a line in the sand between us and the rest of life on this planet. We are rare creatures, but we are not quite so unique as we would like to think. The fossil record makes this abundantly clear.

If anything, it is strange that there are no other kinds of human alive today. In the past our own ancestors inhabited a world that was also home to sister species, like the Neanderthals, but they are all gone now. Indeed, our present understanding of human evolution presents a branching bush, not a straight "march of progress." Even so, the straight-line development of a crouched ape into a human is difficult to fight against.

As Misia Landau pointed out in Narratives of Human Evolution, scientific explanations of human evolution can often be understood in terms of "hero stories." The journey starts with a particular individual, in this case an ape, that over time is given skills or tools by donor figures to overcome challenges. In this way the development of our species mimics the development of the individual, and this model does not mesh well with diversity.

If human evolution were a straight line with one species shading into another, the hero model might work. This is certainly not the case, but even so the hero model is still somewhat favored. Lineages that branched off but became extinct, like the robust australopithecines, are seen as losers, and of little consequence to our own story. This is underlined by the fact that when new hominin fossils are found, the question most immediately on everyone's mind is "Is it one of our ancestors?"

It might be comforting to think that our penchant for evolutionary story-telling was something effectively ended by the middle of the 20th century, but I don't think this is so. Take the announcement that Homo habilis and Homo erectus coexisted in Africa about 1.55 million years ago. It was an important discovery, but to find a potential ancestral species (Homo habilis) overlapping with a potential descendant species (Homo erectus) should not be that surprising.

The hypothesis that the two species had an ancestor-descendant relationship remains intact, as evolution is something that occurs in populations. Species, as a whole, do not have some kind of internal mechanism forcing them to evolve towards a particular form. Some populations will become more derived while others remain in stasis, and that applies to our own family tree as well as any other.

Even when the branching aspect of evolution is grasped, however, too many confuse evolution with progress. Fictional ideas of what the "next evolution" in our future might be like underlines this point. Superpowers, like those possessed by the X-Men or the characters in Heroes, are not just products of science fiction, but reflections of what some might consider the next "superior" development in our species. Concepts of humanoid aliens as feeble but big-brained creatures are also indicative about what we value about ourselves, particularly since such creatures are so unimaginative. (And the same could be said of the Dinosauroid.)

The trouble with all this is that hero stories are much more accessible than the evolutionary reality. We have crowned ourselves as evolutionary victors, and the fact that we are the last remaining twig of a more robust family tree appears to go against the short-sightedness that is often called "common sense." A new narrative is needed, but it will likely have to be one carefully developed from scratch, not co-opted from tradition.

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