Natural Selection didn’t start with Darwin. In fact, it is a very old idea. Ancient, even. After careful study, I now believe that Charles Darwin’s proposal of natural selection was caused by the influence of certain Greek philosophers.
In 1859, Charles Darwin explained the concept of Natural Selection as the mechanism by which things evolve. His idea is pretty simple: Living things reproduce. Variations show up from time to time in the offspring: some are of slightly different color than their parents, some are a little bit larger or smaller, and so on. Some of these variations cause the offspring to survive more often or for a longer period of time than others. A type which survives longer or more often will have more children than competing types that don’t do as well. Since offspring usually (not always) tend to inherit their traits from their parents, most of the offspring that a member of the surviving type has will also have the variation that made its parent so successful. The fact of greater reproduction by types that survive well results in those types becoming more common than others. A concrete example of natural selection is the evolution of pesticide resistance in insects: just as some insects may be smaller or larger than other members of their species, some insects are resistant to pesticides and some are not. That is one of the differences, or variations, within the population. When pesticides began to be used, it meant that insects who could survive exposure would survive to reach adulthood more often than insects that couldn’t. Only those who survive to adulthood can reproduce. New generations are created by the reproduction of the previous generation. Since the previous generation was composed of a large number of pesticide-resistant insects, and since offspring tend to inherit the traits of their parents, it follows that the new generation must have a greater frequency of pesticide-resistance than the generations that lived before pesticide was introduced. The key components of this idea are:
1. Nature Produces Variations.
2. Some Variations Are Good At Surviving, Some Are Not.
3. Variations that are good at surviving stick around
and are still seen today, those that are not perish
and are seen no more.
Therefore, we only see plants and animals that are good at surviving.
Little known fact: Charles Darwin was not the first to hold that life had evolved, nor was he the first person to think of the concept of natural selection. Conway Zirkle, writing in 1903, explains that, “As an explanation for evolution, natural selection involves a number of distinct though subordinate propositions… A number of philosophers and naturalists recognized the validity of one or more of these propositions without however, gaining any clear conception of the implications of the whole doctrine.” The author lists those who “recognized the validity of one or more” of the propositions, and this list includes Immanuel Kant, Benjamin Franklin, and Erasmus Darwin (Charles’ grandfather). “Natural Selection can serve as an alternative explanation of those facts generally cited as evidences of teleology” (design). Zirkle informs us that natural selection was used to this end by the ancient Greek philosopher Empedocles and the Roman poet Lucretius.
The 18th Century Philosopher David Hume had his fictional skeptic Philo put forward a bold and innovative alternative to theistic design. Matter is eternal, says Philo. Matter is always in motion. In an eternity of time, this matter, by sheer chance, must be thrown together in every possible arrangement, including the material arrangement that is the grizzly bear, the venus flytrap, even man. When matter is thrown together in a form that cannot sustain itself, it perishes. When it can sustain itself (and can reproduce) it continues to exist. According to Philo, this explains the apparent design found in living things. Here we have all the components of natural selection: there is variation (matter is thrown into all kinds of different forms) differential survival (some forms perish, others reproduce and continue their lineage through the ages) and the necessary result is the orderly world we see today (only plants and animals good enough to survive). (See Section 8, Dialogues Concerning Natural Religion).
The Roman Poet Lucretius paints a gruesome picture of early life on earth and how it proceeded:
In those days also the telluric world, Strove to beget the monsters that upsprung… Some gruesome Boggles orphaned of the feet, Some widowed of the hands, dumb Horrors too, Without a mouth, or blind Ones of no eye… Thuswise, that never could they do or go… And other prodigies and monsters earth was then begetting… in vain, Since Nature banned with horror their increase, And powerless were they to reach unto The coveted flower of fair maturity… For we see there must Concur in life conditions manifold, If life is ever by begetting life To forge the generations one by one: First, foods must be; and, next, a path whereby The seeds of impregnation in the frame May ooze, released from the members all; Last, the possession of those instruments Whereby the male with female can unite…(Link)
In other words: In the beginning a large number of creatures came to life. Some of them were monsters and did not have those things necessary for survival and reproduction (“dumb Horrors too, Without a mouth, or blind Ones of no eye”). Such monsters died out and did not reproduce (“nature banned with horror their increase”). Life requires certain things to continue to exist and to leave behind offspring (“There must concur in life conditions manifold… Foods must be… A path whereby the seeds of impregnation in the frame may ooze”). The life that exists now is the offspring of previous generations that could live and produce offspring, which necessarily means having “a path for impregnation” and so on. Variation. Differential Survival. Selection.
Charles Darwin had read the works of David Hume. Mark Pallen makes an especially strong case for the Humean influence on Darwin by comparing the writings of the two. Hume cited Lucretius, himself a follower of Epicurus, and said that the character Philo’s bold hypothesis involving eternal matter and chance was a revival of “the Epicurean hypothesis.” I propose that Charles Darwin’s theory of natural selection is directly descended from the speculations of Epicurus and other Greek philosophers. Not only is the chain of influence plausible, it also evidenced by Darwin’s familiarity with Hume and Hume’s familiarity with Epicurus and Lucretius.