DIVERSITY of SPECIES

Someone questioned that loss of diversity is an indication of human overpopulation, as I had suggested in a recent blog on that topic. Granted that perhaps only a naturalist would think so today, when most people are divorced from Nature.

   Birds, city people think, or any other living group, are just out there, on their own, like us perhaps. But, since Darwin, those who study these things have agreed that all of us, bird or man, have a common ancestor. We no longer need “missing links’ to close the deal. The more we study, the more realistic it becomes to consider every living thing as evidence of a successful evolutionary experiment.  Predecessors are history. Birds evolved from reptiles (from a small dinosaur, indeed); and mammals were another offshoot. Some mammals still lay eggs, as though to remind us.

   In 1927 Charles Elton of Oxford, one of the first world-class ecologists (see his Animal Ecology), demonstrated that the whole realm of life is inter-dependent, by drawing a pyramid of numbers. The broad base is occupied by plants, from lichens to grasses, to trees. Only plants, through photosynthesis, can harness the energy of the sun, and thus manufacture carbohydrates from which proteins and other edibles are formed.  This food base allows various animals to specialize as herbivores, whether as insects, mice, or ungulates; they occupy the middle of the pyramid. No plants, no animals. It takes almost ten pounds of grass to make a pound of flesh. Finally, at the apex are carnivores who subsist on herbivores, but only if these are in sufficient quantity. Hence the taper of the pyramid, and the basis of predation. A similar relationship exists in the marine realm.

   In addition, mature terrestrial plant communities make and anchor soil, and modify regional climates. So much so that the planet has at least six rather distinct large plant-animal communities, sometimes called biomes. Within these are niches that we call habitats, occupied by the multitude of species.

   At about the same time, but this time at Harvard, A. N. Whitehead the philosopher gave us a working concept of existence in this corner of the universe.

   All of us borrow from the same pool of building blocks, the atoms and molecules, enriched as this pool may be regionally by the accumulation of evolutionary experiments. We may add a bit of style in our use of these materials, but we pass them on within a century or so. Whitehead said that his studies had yielded no evidence of subjective immortality; but that since we change the world somewhat in passing through it, for better or worse, we achieve some objective immortality.

   Whitehead summed up the process of existence thus:  “The basis of democracy (the common sharing) is the fact of value experience as constituting the essential nature of every pulsation of actuality. Everything has some value for itself, for others, and for the whole.”

   Given this valuational process as the basis of existence itself, a question of morality arises.  He suggested that we have no right to deface the process, but should help maintain the value intensity achieved thus far (see his Modes of Thought, p.111, 1938).

   Practically, then, our numbers, and the greed of too many, currently preempt the evolutionary system’s potentialities for ourselves, at the expense of too many other species. To be responsible members of the life community we should reduce our numbers, fence out the greedy, and let natural processes continue the experiment.