Thursday, February 13, 2014

Missing links

A friend asked me about missing links. For what it's worth, here's my reply:


Keep in mind that I'm no expert. In answer I'll try to first address the question of intermediate forms generally, then discuss hominids, although there may be some necessary overlap in my analysis:

i) Although I think Darwinians use intermediate form and transitional form synonymously, an organism can be an intermediate without being transitional. Take ecological intermediates like semiaquatic species. They share some features with land animals and other features with aquatic animals. That's not because they represent an evolutionary link, but because they function in a habitat that straddles land and water.

ii) I'd say one reason the fauna and flora exhibit such a range of similarities and dissimilarities is that God chose to manifest his wisdom by creating a wide variety of creatures. Ringing the changes on certain basic models. 

iii) A hybrid appears to be an intermediate form. Take ligers (a cross between a lion and a tigress). If a Darwinian was examining the fossil remains of a hybrid, he might well classify it as a transitional form or evolutionary link. Could he tell from the fossil remains that it's actually a hybrid? 

iv) Marsupials are similar to their mammalian counterparts. If all a Darwinian had to go by were fossil remains of extinct marsupials, he might classify a Tasmanian "wolf" as a transitional canid. 

v) Some snakes are oviparous, which they share in common with birds, most fish, and amphibians–but other snakes are viviparous, which they share in common with placental mammals. By Darwinian logic, that would make boas and anacondas an evolutionary link between reptiles and mammals! That's despite the fact that these are considered primitive snakes, compared to more advanced species like pit vipers.  

vi) To my knowledge, fossil remains of hominids are usually skeletal fragments. From skeletal fragments, could a Darwinian tell the difference between a simian child, simian adolescent, and simian adult, or would he classify these as three different taxa? 

Children have smaller skulls than adults. Since encephalization is considered evidence of evolution, would a Darwinian mistakenly classify the skull or skull fragments of an extinct simian child as an earlier hominid? 

Likewise, I believe Cromagnon man had a larger cranium than modern man. If both were extinct, Darwinians would logically classify Cromagnon as later than modern man. 

vii) To my knowledge, disease, diet, and climate can all affect body size, shape, and skeletal structure. Consider the difference between the Tutsi, central African pigmies, Australian aborigines, Eskimos,  and Samoans.

If these were all extinct, and all we had to go by were skeletal fragments, would a Darwinian classify them all as homo sapiens, or would he classify them as different hominids? 

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