Ingenious Artistry in the Origin of Hummingbirds
Please see below the Abstract of my recent article which asks, “Can Neo-Darwinism Explain the Origin and Variation of the Hummingbirds?”
Abstract
Richard Dawkins is one of the leading spokesmen for the evolutionary theory’s modern synthesis (neo-Darwinism). He is in full agreement with virtually all his colleagues when he asserts that “evolution not only is a gradual process as a matter of fact; it has to be gradual if it is to do any explanatory work.” So, the entire array of the fascinatingly different 366 hummingbird species of the family Trochilidae, being “distinctly different than all other avians,” must have evolved by natural selection through — in Darwin’s words — “infinitesimally small changes,” “infinitesimally slight variations,” “insensibly fine steps,” and “insensibly fine gradations.” Many of those gradations are thought to have been due to mutations with only “invisible effects on the phenotype,” according to Ernst Mayr. However,
“Even a new mutation that is slightly favorable will usually be lost in the first few generations after it appears in the population, a victim of genetic drift. If a new mutation has a selective advantage of S in the heterozygote in which it appears, then the chance is only 2S that the mutation will ever succeed in taking over the population. So, a mutation that is 1 percent better in fitness than the standard allele in the population will be lost 98 percent of the time by genetic drift.” (Emphasis added.)
Let us apply this method to individual hummingbird species, including their sexual dimorphism, and the corresponding flower formations of their nectar-producing host plants. Together these imply coordinated inter-kingdom mutations and interactions. Five examples will be discussed in the following article: (1) the strongly curved beaks of the two species of Eutoxeres, (2) Lophornis gouldii (the dot-eared coquette), (3) Docimastes ensifer (Gould) = Ensifera ensifera (the sword-billed hummingbird), (4) Sappho sparganurus (the red-tailed comet), and finally (5) Loddigesia mirabilis (the marvelous spatuletail).
All five examples display sexual dimorphism. Now, sexual selection stands in clear opposition to natural selection. Here that is the case not only because of the fact that “conspicuously colored males preferentially fall victim to their enemies,” but also because their often astoundingly acrobatic behavior to impress the females necessitates a tremendous expenditure of energy for the show. Ontogenetically, it requires development of a strikingly showy and flamboyant plumage. In the present cases, displays by the males in color, size, and shape almost completely dwarf those of the females. (Compare with this the prime example of the phenomenon among the class Aves: the well-known peacock.)
Moreover, to evolve a special preference for brightly colored males with specially formed short and/or long decorative feathers, sexual selection presupposes the occurrence of a series of highly unusual mutations in the females. For these mutations, however, there is not the slightest evidence.
Now, let us look briefly at the species mentioned above, in reverse order. We begin with (5) Loddigesia, whose males possess two stunningly long tail feathers ending in large flat violet-blue discs (see the photo at the top of this article). To evolve in a process of continuous evolution, this would mean thousands of unknown mutations — mutations, again, with “slight or even invisible effects on the phenotype,” each new step implying the substitution of the entire population of birds. All this would have happened regularly in opposition to natural selection. The females, however, have been described as “not easily impressed” by the show of the males. So, one may ask: are there really decisive selective advantages for the survival of spatuletail populations due to changes of about 1 millionth of 1 meter or 1 thousandth of 1 mm of the male’s two tail feathers?
For each species, this immensely improbable process of continuous evolution implies thousands of mutations, with visible or invisible effects on the phenotype, each time selected with certainty by the respective females. This observation applies to (4) the “deeply forked, spectacular, long, iridescent, golden-reddish tail, longer than the length of the body,” of Sappho sparganurus (the red-tailed comet); (3) the enormously long bill distinctive of Docimastes ensifer (the sword-billed hummingbird); (2) the “long dark rufous feathers [that] on its crown form a crest” plus the “long white feathers with shiny green dots [that] make tufts that fan out and back on the cheeks” of Lophornis gouldii (the dot-eared coquette); and (1) the strongly curved beaks of the two species of Eutoxeres (the sicklebills), seemingly in coordination with the flower forms of Centropogon and Heliconia.
If neo-Darwinian theory cannot explain even differences between the hummingbirds themselves (including their sexual dimorphism), what then can we expect when it comes to the origin of the entire family of this anatomically and physiologically well-defined group of birds? From an evolutionary standpoint, we must agree with many hummingbird researchers, including the clear statement of Jillian Mock, that “the origins of hummingbirds are still a major mystery.”
With this in mind, we turn to the theory of intelligent design (ID). According to Stephen Meyer, “The theory of intelligent design holds that certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection.” ID, writes Michael Behe, is usually recognized by “a purposeful arrangement of parts.” In what follows I argue that the origin of hummingbirds reflects brilliant, ingenious artistry, not the work of an endless number of infinitesimally small coincidences, haphazardly chained together by the “truly hideous process” of natural selection, “rife with happenstance, contingency, incredible waste, death, pain and horror,” etc.
In contrast with neo-Darwinism, I conclude that an absolutely ingenious artist was at work here, transcending all human abilities, ideas, and powers.
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