Farish Jenkins, a paleontologist who discovered fossils of animals evolving into something new — most notably a 375-million-year-old fossilized fish with skull, neck, ribs and part of the fins that resembled the earliest mammals — died on Nov. 11 in Boston. He was 72.
The cause was complications of pneumonia, said his daughter-in-law, Susan Jenkins. She said he had multiple myeloma, a cancer of plasma cells.
Darwin said proof of his evolutionary theories would be found in fossils, and Dr. Jenkins used them to show life-forms changing into other forms, so-called missing links. His fish, for example, had body parts that were clearly morphing into those of land animals. Similarly, he built on existing knowledge that a group of reptiles were ancestors of mammals with fossil evidence to show how this happened: the reptilian jaw morphed into part of a mammalian inner ear.
He worked in the laboratory as well as on field digs from Arizona to Africa to the Arctic. As part of his vast exploration of how animals walk, trot, gallop and otherwise get about, he studied X-ray movies of starlings in flight. He learned that a bird's wishbone functions as a spring.
"This is well known to everybody in the world," he said after his finding appeared in the journal Science. "It's only scientists who discover the obvious."
Dry wit was only part of his personality. He delighted his Harvard students with his "Moby-Dick" lecture, in which he impersonated Captain Ahab stomping around on a peg leg to demonstrate human locomotion. He used sharpened colored chalk to draw intricate anatomical illustrations. When digging for fossils near the North Pole, he wore his trademark Czechoslovak rabbit-fur hat, and carried a flask of vodka for warmth and a rifle for warding off polar bears. Back home, he favored suits with vests, tiepins and a pocket watch.
"He cut a seriously dashing figure," said Neil Shubin, a University of Chicago paleontologist who worked closely with Dr. Jenkins.
Dr. Jenkins's most heralded find was the fossil fish that he and two other paleontologists, Dr. Shubin and Edward B. Daeschler of the Academy of Natural Sciences in Philadelphia, announced in 2006 in the journal Nature. It was the product of extreme paleontology: the team made four trips over six years to a site on Ellesmere Island, 887 miles from the North Pole, subsisting mainly on chocolate bars. Fiendish weather limited excavation to only one month a year, July. Even though the nature and age of the exposed rocks seemed propitious for finding fossils, they had almost given up when they made their big find.
The trove of fossils they unearthed enabled them to recreate a crocodile-like animal. What it showed was an organism, guided by genes, rearranging itself.
With fish characteristics like scales and fins still evident, new features like a neck appeared: it would have allowed a ground-rooted creature to swivel its head to snare prey. The skull's shape had features that resembled fish, and others that resembled later land animals. Most intriguing, the fins had an elbow joint and the beginnings of wrists that would have allowed the animal to lift itself out of shallow water. It had both gills and lungs.
"This really is what our ancestors looked like when they began to leave the water," the zoologist Jennifer A. Clack of the University of Cambridge and the biologist Per Erik Ahlberg of the University of Uppsala in Sweden wrote in an accompanying editorial in Nature.
H. Richard Lane of the National Science Foundation said, "Human comprehension of the history of life on Earth is taking a major leap forward."
Dr. Jenkins located remains of many of Earth's oldest creatures. Among them was a tiny shrewlike animal he found in Arizona's Painted Desert in 1981. It represented a newly discovered family of warm-blooded creatures. Around the same time, he found a turtle and frog that were then among the oldest ever identified.
He gladly left human evolution for others. "It's not a field for gentlemen," he said. "Those anthropologists are savage."
The eldest of three sons of a marketing executive, Farish Alston Jenkins Jr. was born in Manhattan on May 19, 1940. He graduated from Princeton with a major in geology and earned a master's degree and a Ph.D. from Yale, where he was the first graduate student allowed to take anatomy courses in the medical school. He taught at Columbia before moving to Harvard in 1971.
Dr. Jenkins is survived by his wife, the former Eleanor Bristol Tracy; his son, Henry Edgar Jenkins III; his daughter, Katherine Temperance Jenkins Leeds; his brother, Henry Edgar Jenkins II; and two granddaughters.
In 2010, scientists found fossil footprints in a quarry in Poland 25 million years older than Dr. Jenkins's find. Creationists said these proved that the ancient fish Dr. Jenkins had found could not have been a missing link, since creatures into which they supposedly evolved were already long extant. Dr. Shubin responded that the prints had no fingers or toes, and in any case were inconclusive without a skeleton. He and Dr. Jenkins planned another Arctic trip to find even older bones.
Dr. Jenkins, who Dr. Shubin said loved expeditions more than anything but was debilitated by cancer, did not make the trip. He had told friends that he, as a paleontologist, felt at peace with his mortality, The Economist magazine reported. "I'm familiar with extinction," he said.
Anda sedang membaca artikel tentang
Farish Jenkins, Fossils Expert, Dies at 72
Dengan url
https://scienceteko.blogspot.com/2012/12/farish-jenkins-fossils-expert-dies-at-72.html
Anda boleh menyebar luaskannya atau mengcopy paste-nya
Farish Jenkins, Fossils Expert, Dies at 72
namun jangan lupa untuk meletakkan link
Farish Jenkins, Fossils Expert, Dies at 72
sebagai sumbernya
0 komentar:
Posting Komentar