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To: Junior
Most families, orders, classes, and phyla appear rather suddenly in the fossil record, often without anatomically intermediate forms smoothly interlinking evolutionarily derived descendant taxa with their presumed ancestors.

Eldredge, N., 1989
Macro-Evolutionary Dynamics: Species, Niches, and Adaptive Peaks
McGraw-Hill Publishing Company, New York, p. 22




The record jumps, and all the evidence shows that the record is real: the gaps we see reflect real events in life's history -- not the artifact of a poor fossil record.

Eldredge, N. and Tattersall, I. (1982)
The Myths of Human Evolution
Columbia University Press, p. 59




The fossil record suggests that the major pulse of diversification of phyla occurs before that of classes, classes before that of orders, and orders before families. This is not to say that each higher taxon originated before species (each phylum, class, or order contained at least one species, genus, family, etc. upon appearance), but the higher taxa do not seem to have diverged through an accumulation of lower taxa (Erwin, Valentine, and Sepkoski, 1988).

Erwin, D., Valentine, J., and Sepkoski, J. (1988)
"A Comparative Study of Diversification Events"
Evolution, vol. 41, p. 1183
105 posted on 02/20/2003 4:52:50 PM PST by CaptainJustice (Get RIGHT or get left.)
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To: CaptainJustice
Here's a nugget from the Quote Mine for your edification. Please note how Gould explains why Darwinism predicts that fossils should show a pattern of relatively few transitional fossils between large numbers of similar fossils:
The modern theory of evolution does not require gradual change. It in fact, the operation of Darwinian processes should yield exactly what we see in the fossil record. It is gradualism that we must reject, not Darwinism. ... Eldredge and I believe that speciation is responsible for almost all evolutionary change. Moreover, the way in which it occurs virtually guarantees that sudden appearance and stasis shall dominate the fossil record. All major theories of speciation maintain that splitting takes place rapidly in very small populations. The theory of geographic, or allopatric, speciation is preferred by most evolutionists for most situations (allopatric means "in another place"). A new species can arise when a small segment of the ancestral population is isolated at the periphery of the ancestral range. Large, stable central populations exert a strong homogenizing influence. New and favorable mutations are diluted by the sheer bulk of the population through which they must spread. They may build slowly in frequency, but changing environments usually cancel their selective value long before they reach fixation. Thus, phyletic transformation in large populations should be very rare — as the fossil record proclaims. But small, peripherally isolated groups are cut off from their parental stock. They live as tiny populations in geographic corners of the ancestral range. Selective pressures are usually intense because peripheries mark the edge of ecological tolerance for ancestral forms. Favorable variations spread quickly. Small peripheral isolates are a laboratory of evolutionary change.

What should the fossil record include if most evolution occurs by speciation in peripheral isolates? Species should be static through their range because our fossils are the remains of large central populations. In any local area inhabited by ancestors, a descendant species should appear suddenly by migration from the peripheral region in which it evolved. In the peripheral region itself, we might find direct evidence of speciation, but such good fortune would be rare indeed because the event occurs so rapidly in such a small population. Thus, the fossil record is a faithful rendering of what evolutionary theory predicts, not a pitiful vestige of a once bountiful tale.
Stephen J. Gould, The Panda's Thumb: Reflections in Natural History, 1980, pp182-184


112 posted on 02/20/2003 5:24:11 PM PST by jennyp (http://crevo.bestmessageboard.com)
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