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Earth, only 2 million of which have been identified thus far. Most of the species identified are either born with the capacity to find sustenance and avoid predation sufficiently well that some survive long enough to reproduce, or they are born in such large numbers that some survive long enough to reproduce. It is the ability of such organisms to reproduce that determines what genes constitute the gene pool for the future generations of that species. These genes, in turn, shape the structure and function of the organisms that constitute a species. This reasoning led George Williams (2) to suggest a half century ago that traits (i.e., behavioral tendencies) which benefit the group at the expense of the individual would evolve only if the process of group-selection was great enough to overcome selection within groups. He further suggested that group selection is nearly always weak, so that group-related adaptations do not exist (3). Richard Dawkins (1) popularized the notion that traits which evolve are adaptive at the gene level through his use of the metaphor of the selfish gene. Genes serve their own selfish interests in the sense that whatever the contributions made by a gene, or set of genes, to an organism’s structure and function would be passed on to the next generation if and only if the gene made its way to the gene pool. Survival of the fittest now had a biological basis.

United We Stand, Divided We Fall

Charles Darwin did not know that genes were the mechanism through which structures and behaviors evolved, but an important component of his original theory was the notion of survival of the fittest. Darwin was also puzzled by the observation that many individual organisms made themselves less fit so that the group might survive. Subsequent generations of evolutionary biologists realized that even though genes might act as if selfish, the vehicle responsible for the transport of these genes to the gene pool occasionally extended beyond the individual or parent to kin and even to unrelated members of groups. More specifically, in some cases the superorganismal structures formed by social organisms represent naturally selected levels of organization above individual organisms (4).

Consider the example of the Emperor penguin (Aptenodytes forsteri). Emperor penguins typically reside near their food source of squid, shoaling fish, and small crustaceans but in early winter they gather into breeding colonies (rookeries) up to 60 miles inland in April and May during the Antarctic winter. They search for their mate from the previous year, and go through a courtship ritual before mating. The female lays only one egg in May or June, which coincides with the start of the bitter Antarctica winter. The Emperor penguins are thought to have developed this unusual winter breeding behavior to permit the chick to grow to independence the following summer, when food is plentiful. Ensuring the chick survives that long is a collective enterprise, with the vehicle responsible for the chick surviving long enough such that it too can reproduce not being solely the mother or the father but also the huddle.

The birthing of the egg leaves the mother depleted, so she must return to the seaside to feed while the father assumes responsibility for the incubation of the egg during the winter. An egg from an Emperor penguin will quickly freeze if left exposed to harsh winter conditions of the Antarctica, so the

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