ScffiNCE Lite 



o 



o 

 > 



A Spinal 

 Column 



Who 's winning: Big, smart 



humans? Small, dumb mice? 



Or chiropractors? 



by Roger L. Welsch 



Folklorist Henry Glassie quotes the Ap- 

 palachian mountain man who, when asked 

 about the history of his region, responded, 

 "First there was the dinosaurs... and then 

 Daniel Boone... and here we are!" The 

 breadth of that view is hard to beat, but pa- 

 leontologists at the American Museum of 

 Natural History hope to meet the chal- 

 lenge. Between now and 1996, the Mu- 

 seum will open six exhibition halls filled 

 with fossils that illustrate the evolution of 

 vertebrates, or animals with backbones. 

 This is a massive undertaking, even if it 

 excludes Congress. According to a new 

 Museum guidebook, vertebrates include, 

 for example, sharks, salamanders, Uzards, 

 kangaroos, and horses. Phew, imagine the 

 surprise of the kangaroos when they show 



up at their 500-million-year family re- 

 union and get a look at those relatives! 



The first two halls that are opening, 

 states the guidebook, "feature the group to 

 which humans belong, mammals and their 

 extinct relatives." To my mind, those 

 tacked on words — "and their extinct rela- 

 tives" — represent the most mysterious 

 branches of the evolutionary tree. Why did 

 some family lines continue and change, 

 while others died out? 



I don't keep up with the finer points of 

 the biological sciences beyond what I read 

 on the front cover of the National En- 

 quirer while I am waiting at the grocery 

 store checkout counter ("Stranded Ahen 

 Fathers Child of Zsa Zsa Gabor!"). But it's 

 my impression that trying to find logic or 

 pattern within the processes of natural se- 

 lection is right up there with following a 

 teen-age daughter's explanation of why 

 she missed her curfew. 



Turtles make sense to me. Years ago, a 

 Mend of mine who operated a gravel-pit 

 pump came roaring into my yard, excited 

 because he believed he had dredged from 

 his Pleistocene glacier rubble a petrified 

 human brain. At first glance I recognized 

 that what he held in his hand was not a 

 brain but a turtle, turned to limestone mil- 

 lenniums ago. I could even recognize what 

 kind of turtle it was — a Blandings or some 



mighty close relative. Turtles represent 

 evolution at its best, a creature built to last. 

 I've watched coyotes and cows paw at 

 closed turtles and tortoises without dam- 

 aging them. Flood, drought, fire, famine, 

 isolation. . .turtles take them all in slow but 

 steady stride. Little wonder that turtles 

 have survived. 



Now, explain to me how the opossum 

 has made it this far, right along with the 

 Blandings turtle. The moment the first 

 possum fainted away in terror upon en- 

 countering a coyote, the possum should by 

 all reason have become extinct. But not ten 

 days ago. Lovely Linda came in to tell me 

 some savage creature was asleep in the 

 chicken house, and when I went out to in- 

 vestigate, there he was — oF possum, terri- 

 fied into a coma by a rooster. Pink-nosed, 

 pink-toed, and utterly defenseless, he was 

 a generous lunch for anyone so inclined. 



The fossil skull of a coyote (left) was 

 found crushed beneath the bones of a 

 mammoth. The coyote may have been 

 standing too close to the dying mammoth 

 when it fell or when its carcass shifted. 

 A modem skull (right) is intact. 



Ken Bouc, NEBRASKAIand Magazine; Nebraska Game and Parks Commission 



26 Natural History 6/94 



