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Early Man. Sean Pitman, MD December 2008. www.DetectingDesign.com. How to interpret the bones?.
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Early Man Sean Pitman, MD December 2008 www.DetectingDesign.com
How to interpret the bones? • “You can with equal facility model on a Neanderthaloid skull the features of a chimpanzee or the lineaments of a philosopher. These alleged restorations of ancient types of man have very little if any scientific value and are likely only to mislead the public.... So put not your trust in reconstructions.” • Earnest A. Hooten, Harvard professor of Anthropology, “Reconstructions?” Up from the Ape, pp. 332
“A great legend has grown up to plague both paleontologists and anthropologists: That a man can take a tooth or a small and broken piece of bone, gaze at it, and pass his hand over his forehead once or twice, and then take a sheet of paper and draw a picture of what the whole animal looked like as it tramped the Terriary terrain. If this were quite true, the anthropologists would make the F.B.I. look like a troop of Boy Scouts.” • William W. Howells, Harvard professor of Anthropology, Mankind so Far, pp. 138
So, what’s the problem? • Why is anthropology so problematic when it comes to interpreting the meaning of bones? Are many mainstream beliefs based on real science? – or blind faith in fairytale stories that have grown into legends? • A bit of history . . .
Piltdown Man • Eanthropus dawsoni or “Dawn Man” • “Discovered” by Charles Dawson in 1912 (an ape-like mandible with human-like teeth and a human-like piece of skull) • In 1953 Oakley, Weiner and Clark exposed Piltdown Man as a deliberate hoax • Interesting because this rather obvious hoax was accepted by the scientific community as real evidence of human-ape ancestry for over 40 years
Nebraska Man • Hesperopithecus haroldcookii • Mr. Harold Cook discovered one tooth in 1922 in the Pliocene deposits of Nebraska • An attempt was made to use Nebraska Man as evidence in the Scopes “Monkey Trial” • Drawing published in Illustrated London News, 1922
Around the time of the Scopes Monkey trial (1925), Osborn chided Nebraska native William Jennings Bryan in the press: “The earth spoke to Bryan from his own state of Nebraska. The Hesperopithecus tooth is like the still, small voice. Its sound is by no means easy to hear---. This little tooth speaks volumes of truth, in that it affords evidence of man's descent from the ape.” American Museum of Natural History
“Such a drawing or 'reconstruction' would doubtless be only a figment of the imagination, of no scientific value, and undoubtedly inaccurate.” - Henry Osborn Wolf J. and Mellett J.S., The role of "Nebraska man" in the creation-evolution debate. Creation/Evolution, Issue 16:31-43., 1985 London Daily News, 1922
Little did Osborn know Just how inaccurate this drawing was • Turned out to be a tooth from an extinct type of pig (peccary) • I wonder how the history would remember the Scopes trial if this little bit of information had become available during the trial?
Java ManMix-n-Match • Pithecanthropus erectus • Found by Eugene Dubois between 1891 and 1892 • Association of a human-like femur with a very large gibbon-like skullcap, found 12 meters apart • The false association was eventually recognized and Java Man was removed from the American Museum of Natural History and the Leiden Museum (1980s)
Getting it in the Right Ballpark Sort of . . .
Evolutionary Sequence from ape to human
Ramapithecus lufengensis • In 1932 Louis Leaky discovered a fragmented maxilla and some teeth in southwest Kenya • Assembled to form a parabolic shape similar to the human condition • Presented as the first branch of ape to evolve into humans 12 to 14 million years ago
Problem: • A full jaw (mandible) was discovered • In 1977 a full Ramapithecus jaw bone was discovered but was U-shaped • Zilman and Lowenstein attempt to explain the reason for the earlier thinking of most of the worlds most prominent paleoanthropologists: • “Ramapithecus walking upright has been reconstructed from only jaws and teeth. In 1961 an ancestral human was badly wanted. The prince's ape latched onto position by his teeth and has been hanging on ever since, his legitimacy sanctified by millions of textbooks and Time-Life volumes on human evolution.”
Australopithecus afarensis "LUCY" • Discovered in 1974 by Donald Johanson • Angle of knee joint matched that of humans • The joint angle also matched that of tree climbing apes • Also had curved toes bones, high arm to leg length ratio, and many other features identical to tree climbing apes • Was Lucy just a tree climbing ape or did she walk upright?
Stern and Susman detail many features consistent with tree-climbing apes for A. afarensis • Yet, they believe that A. afarensis spent much time running around on two legs? Why? “The most significant features for bipedalism include shortened iliac blades, lumbar curve, knees approaching midline, distal articular surface of tibia nearly perpendicular to the shaft, robust metatarsal I with expanded head, convergent hallux (big toe), and proximal foot phalanges with dorsally oriented proximal articular surfaces.” (McHenry 1994)
Interpreting the Same Things in Different Ways • The perpendicular tibia, lumbar curve, and angled knee joints that are "approaching midline" are seen in modern tree-climbing monkeys • The "robust" first metatarsal with an expanded head is also consistent with Stern and Susman's comment that the hand bones (and reasonably the foot bones as well), "have large heads and bases relative to their parallel sided and somewhat curved shafts, an overall pattern shared by chimpanzees" and that this, "might be interpreted as evidence of developed grasping capabilities to be used in suspensory behavior."
3.6 million year old footprints with modern human features, adult and child • Happen to be about as old as Lucy • How can Lucy be a “missing link” if modern human posture and gait were already evolved?
“As I kneel beside the large print and lightly touch its sole, I am filled with quiet awe. It looks perfectly modern. ‘I thought that at three and a half million years ago their prints might be somehow different from ours,’” says Latimer. “But they aren’t. The bipedal adaptation of those hominids was full-blown.” • Gore, R. National Geographic, Feb. 1997
Johanson insisted strongly that the Laetoli footprints simply would have to have been made by his A. afarensis (i.e. Lucy): “The foot prints would have to be from A. afarensis. They substantiate our idea that bipedalism occurred very early, and our contention that the brain was too small to master tools.”
Problem: • The foot bones and lower leg of A. africanus (Lucy) have been recently found (in Hadar) • These foot and leg bones are apelike
More Problems for Johanson • KNMER1470 found in 1972 with a modern human femur • More human-like skull than Lucy • Ash atop 1470 originally dated (1969) by K-Ar at ~220 Ma by multiple labs • This dating done before 1470 found • After 1470 found ash redated over and over again until the “best” date was placed at 2.61 Ma • Lucy originally dated at 2.9 Ma • KNMER 1470 re-dated using Basil Cook’s pig teeth sequences to less than 2 Ma and Lucy to more than 3 Ma
Richard Leakey, June of 1973, in an interview with National Geographic: "Either we toss out the 1470 skull or we toss out all our theories of early man. It simply fits no previous models of human beginnings. 1470 leaves in ruin the notion that all early fossils can be arranged in an orderly sequence of evolutionary changes."
Zinj • Discovered in 1959 by Mary Leakey • Found with stone tools and evidence of “butchered” animals • Given name of “Handy Man” or Homo habilis – supposedly evolved after/from Lucy (Australopithecines) • Does Zinj look at all like KNMER 1470? (Both are Homo habilis) • Fossil and living Coelacanths that were given different genus and species names yet look far more similar than Zinj and KNM-ER 1470 • discussed in lecture on the Fossil Record
Dr. Spoor’s research on semicircular canals of H. erectus, Australopithecus, and many other hominids indicates that H. habilis, "relied less on bipedal behavior than the australopithecines." And yet, H. Habilis is supposed to be more advanced than australopithecines?
Leakey, 1990PBS documentary: “If pressed about man's ancestry, I would have to unequivocally say that all we have is a huge question mark. To date, there has been nothing found to truthfully purport as a transitional specie to man, including Lucy, since 1470 was as old and probably older. If further pressed, I would have to state that there is more evidence to suggest an abrupt arrival of man rather than a gradual process of evolving.”
“The australopithecines are rapidly shrinking back to the status of peculiarly specialized apes…” • Matt Cartmill, Duke; David Pilbeam, Harvard; Glynn Isaac, Harvard, American Scientist, July-August 1986, p.419
Neandertal (Neanderthal) Man (Homo neanderthalensis) • Thought to have died out over 20,000 years ago. • First found in 1856 in Neander Valley, Germany • JohannFahlrott (a school teacher) • Dozens of skeletons have since been found • In 1908, Professor Boule of The Institute of Human Paleontology in Paris declared Neanderthal an ape-man because of his low eyebrow ridges and the stooped over posture of some of the specimens
Compared to Modern Humans: • Neanderthals had bigger brains (>200cc) • Lived a long time (stooped by osteoarthritis) • Dr. Rudolph Virchow argued in 1872 that Neanderthals were modern humans with rickets and arthritis • The Chicago Field Museum has since put in a newer exhibition of Neanderthal man looking more fully human • What’s the latest “scientific” explanation? • Neanderthal man was an “evolutionary dead-end”
What about DNA? • July 11, 1997, Neanderthal mitochondrial DNA (mtDNA) successfully recovered and sequenced by Svante Pääbo et. al. (Cell) • mtDNA recovered three times • Pääbo’s Conclusion: Evolutionary divergence from modern humans some 550,000 to 690,000 years ago
Max difference between human and human: • Ave. Human Difference: 8 ± 3.0 • Intra-Human Range: 1 – 35 differences (1999) • Ave. Human-Neandertal Difference: 25.6 ± 2.2 • Human-Neandertal Range: 20 – 34 • Ave. Human-Chimp Difference: 55.0 ± 3.0 • Human-Chimp Range: 46-67 • Intra-Chimp Range: (1-81) • Overlaps between humans and Neandertals • Might be 35 differences from the guy sitting next to you and only 20 differences from a Neandertal • A human-chimp “relationship” might be closer than a chimp-chimp “relationship” • Human-chimp difference might be only 46 while a chimp might be 81 differences from another chimp
Using Pääbo’s logic, one might rightly call one’s next-door neighbor a “Neandertal”
Further confusion from Pääbo’s article: • Neanderthal mtDNA was actually farther away from chimp mtDNA than that of modern humans • We “modern” humans are therefore more chimp-like than Neanderthals?! • Or, within the range of ethnic variation?
mtDNA as a Molecular Clock: • Recently called into question by articles in several well-known journals like Science • Clock off by as much as “20-fold” • Mitochondrial Eve, once thought to be 100,000 to 200,000 years old, might now have to be revised to as young as “6,000 years old” (Parsons et al)
A more recent 2007 study: • “Comparisons suggest large differences: the mutation rate estimated from pedigrees of humans is a hundredfold higher than the substitution rate for the primate mitochondrial DNA control region. . . We await the more rigorous type of assessment with some nervousness, given that we suspect they might reveal that many past studies placed too much confidence in simple molecular clock analyses, and that their conclusions should thus be revisited.” • Mario J.F. Pulquerio and Richard A. Nichols, Dates from the molecular clock: how wrong can we be? Science Direct, Trends in Ecology and Evolution, Vol. 22, No. 4, 2007
A mathematical model: • “These analyses suggest that the genealogies of all living humans overlap in remarkable ways in the recent past. In particular, the MRCA of all present-day humans lived just a few thousand years ago [~3-4000 B.C.] in these models. Moreover, among all individuals living more than just a few thousand years earlier than the MRCA, each present-day human has exactly the same set of genealogical ancestors.” • Douglas L. T. Rohde, Steve Olson & Joseph T. Chang, Modeling the recent common ancestry of all living humans, Nature 431, Accepted 14, July 2004
In 1937, Germaine Henri-Martin, a very well respected archeologist, began excavations in a cave in southwestern France called Fontéchevade and continued her work here until 1954, removing over 900 cubic meters of sediment • Discovered “first Frenchmen” older than Neanderthals
Many layers found • The topmost layers: "Aurignacian" (modern) • Underneath the Aurignacian: "Mousterian" layers, laid down during the time of the Neandertals • Below the Mousterian: "Tayacian" layers within which she found several human skull fragments and evidence for the living conditions of these “first Frenchmen”