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Tell the World What the Experts Now Know

Tell the World What the Experts Now Know


This is not exactly recent news, but the one hundredth birthday of evolutionist Ernst Mayr draws renewed attention to it. Within the past thirty years, the standard view of evolution theory has been shown to be woefully inadequate.

The experts, in response, have not sat around to bemoan the situation. Instead, they have simply executed a dramatic about face, and all have marched smoothly off in the opposite direction. They have carried public policy with them too. Everyone is reacting to the embarrassing finding, with nobody admitting that there ever was a problem.

Ernst Mayr is the last survivor of the golden age of the “Evolutionary Synthesis”, developed during the period 1930-1950. This man, on the occasion of his birthday in July, naturally used the occasion to reflect on the significance of his work. It was his early interpretation, supported by colleagues at a meeting in Princeton in 1947, which popularized the small populations approach to the origin of species. This view became conventional wisdom for a long time to come. For example, prominent ecologist Eugene Odum articulated this view in the 1971 edition of his textbook Fundamentals of Ecology. As described by Odum, new species arise mainly through the process of geographic isolation (p. 241). He even pointed to the Galapagos finches as a prime example of this phenomenon.

The idea is that on an island, new mutations in a small population might allow the following generations there to adapt rapidly to a novel environment. Thus in the case of finch populations, each on a separate island in the Galapagos archipelago, a population might exploit a new food resource and thus develop into a new species. The real situation there however is that no island (except the tiniest outcrops) has only one species. Some have as many as ten. (David Lack. 1953. Darwin’s Finches. Scientific American 188 #4 pp. 66-71). On a single island, interbreeding of the population would prevent diversification (appearance of new species). How did multiple species get there?

To make the geographic isolation scenario work, scientists had to suppose that individual species emerged on separate islands and then all invaded the territory of other species. There is no evidence for this process, of course. One might more logically conclude that all these species arrived together from the mainland.

Subsequent to the 1947 meeting, everyone knew, or thought they knew, that island archipelagos were an important site for the production of biological diversity (lots of new species).

More recently however, studies in nature have revealed that islands are bad news as far as increases in diversity are concerned. One such “experiment” has continued for ninety years. It was in 1914 that the building of the Panama Canal led to the flooding of Lake Gatun. A host of tiny islands appeared in the lake. These had formerly been hilltops, all fully covered by the lush rainforest typical of the area. Now however, they were isolated landscapes, some as small as 0.1 hectare, others of 0.8 hectare to 7 hectares, with one big specimen: Barro Colorado Island with 1500 hectares. This latter island (along with five adjacent peninsulas) was established as a nature monument in 1923. Since 1946 the Smithsonian Institute has administered the facility.

One of the important projects carried out by Smithsonian scientists has been to compare the diversity of tree species on the islands with that on the adjacent mainland. Initially the entire landscape was connected and thus these sites were similar in overall composition and diversity. However, during the next 75 years after the isolation of the islands, the variety of species found on each island plunged dramatically. The rate of decline was discovered to be 30-40 times greater than the experts had expected on the basis of chance “adverse events”.

This shocking discovery provided quite a dilemma for biologists. Obviously such rapid declines were far faster than any process of speciation could be expected to work. The islands, which were losing the diversity they already had, could scarcely be expected to produce new diversity. It is evident that geographic isolation such as in island archipelagos, does not lead to an evolutionary increase in new species.

The Smithsonian is now researching a similar phenomenon, the effect of fragmentation of the rainforest through deforestation. Established in 1979 near Manaus, Brazil, this research facility is comparing rainforest fragments with adjacent continuous forest. Other studies had shown results similar to the Panama Canal study. According to a 1967 monograph entitled The Theory of Island Biogeography (Princeton University Press) by Robert H. MacArthur and E. O. Wilson, new species spread from adjacent continents out to remote islands such as Fiji. Once there, new species replace older ones which had previously arrived. Thus animal communities on islands are greatly affected by immigration and local extinction. Speciation is not a factor.

Another author, John Terborgh (1974. BioScience 124. pp. 715-722) studied islands which, only thousands of years ago, presumably had animal communities similar to the mainland. Assuming his basic assumptions were correct, what he found was that some “unrelenting forces yet to be identified” had led to marked declines in biodiversity. He thus concluded that only large natural reserves, at least one thousand square kilometers in extent, are adequate to prevent a rush of extinctions.

One might suppose that evolutionists would now revert to plan B, that is to call upon large populations to increase biodiversity. Unfortunately we already know that new mutations have little hope of spreading in large populations. The chance that mating individuals will both carry the same mutations, is very small indeed in a large population. Without expression of the mutation, the potential for selection, favourably or otherwise, is small.

With the knowledge that small or fragmented populations are not the raw material of evolution, as formerly supposed, but rather lead to extinctions, prominent biologists have now begun to advocate the preservation of huge tracts of natural lands. Thus in western North America, prominent individuals have advocated the Y2Y Yellowstone to Yukon wildlife corridor and also in eastern North America, the A-to-A Algonquin Park to Adirondack Park wildlife corridor. The idea is that we need huge tracts of protected land if we are to maintain the present level of biodiversity. In western Canada, at least, governments are already attempting to protect “buffer zones” and “access corridors” around and between various parks.

Whatever the merits of these policies, no one is mentioning that the whole approach is a striking indictment of evolution theory. Dr. Mayr, however, is not admitting anything. At 100 years of age, he is still busy attacking the “creationists”.

Margaret Helder
December 2004

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