lecture 1 - early man

7/31/2019 Lecture 1 - Early Man

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Sean Pitman, MDDecember 2008


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Earnest A. Hooten, Harvardprofessor of Anthropology,Reconstructions? Up from theApe, pp. 332


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William W. Howells, Harvardprofessor of Anthropology, Mankindso Far, pp. 138


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Eanthropus dawsoniorDawn Man

Discovered by CharlesDawson in 1912 (an ape-likemandible with human-like teeth

and a human-like piece of skull) In 1953 Oakley, Weiner and

Clark exposed Piltdown Man asa deliberate hoax

Interesting because this ratherobvious hoax was accepted bythe scientific community as realevidence of human-apeancestry for over 40 years


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Hesperopithecus haroldcookii

Mr. Harold Cook discovered onetooth in 1922 in the Pliocene

deposits of Nebraska An attempt was made to use

Nebraska Man as evidence inthe Scopes Monkey Trial

Drawing published in IllustratedLondon News, 1922


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American Museum of Natural History


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London DailyNews, 1922

Wolf J. and Mellett J.S., The role of "Nebraska man" in the creation-evolution debate. Creation/Evolution, Issue 16:31-43., 1985


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Little did Osborn know Just howinaccurate thisdrawing was

Turned out to be a tooth from an extinct type of pig(peccary)

I wonder how the history would remember theScopes trial if this little bit of information hadbecome available during the trial?


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Pithecanthropus erectus

Found by Eugene Dubois between1891 and 1892

Association of a human-like femurwith a very large gibbon-likeskullcap, found 12 meters apart

The false association was eventuallyrecognized and Java Man wasremoved from the AmericanMuseum of Natural History and theLeiden Museum (1980s)


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Sort of . . .


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Evolutionary Sequencefrom ape to human


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In 1932 Louis Leaky discovered afragmented maxilla and some teeth insouthwest Kenya

Assembled to form a parabolic shapesimilar to the human condition

Presented as the first branch of ape toevolve into humans 12 to 14 millionyears ago


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Problem:

A fulljaw (mandible) was discovered

In 1977 a full Ramapithecusjaw bone wasdiscovered but was U-shaped

Zilman and Lowenstein attempt to explainthe reason for the earlier thinking of most of

the worlds most prominentpaleoanthropologists: Ramapithecuswalking upright has been

reconstructed from only jaws and teeth. In 1961

an ancestral human was badly wanted. Theprince's ape latched onto position by his teethand has been hanging on ever since, hislegitimacy sanctified by millions of textbooks andTime-Lifevolumes on human evolution.


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Evolution of Ramapithecus


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Gorilla Skull


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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 featuresidentical to tree climbing apes

Was Lucy just a tree climbing ape or didshe walk upright?


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Stern and Susman detail many features consistent

with tree-climbing apes for A. afarensis Yet, they believe that A. afarensisspent much time

running around on two legs? Why?

The most significant features for bipedalism includeshortened iliac blades, lumbar curve, knees approachingmidline, distal articular surface of tibia nearlyperpendicular to the shaft, robust metatarsal I withexpanded head, convergent hallux (big toe), and

proximal foot phalanges with dorsally oriented proximalarticular surfaces. (McHenry 1994)


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The perpendicular tibia, lumbar curve, and angled kneejoints that are "approaching midline" are seen in moderntree-climbing monkeys

The "robust" first metatarsal with an expanded head isalso consistent with Stern and Susman's comment thatthe 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 patternshared by chimpanzees" and that this, "might beinterpreted as evidence of developed graspingcapabilities to be used in suspensory behavior."


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3.6 million year old

footprints with modernhuman features, adultand child

Happen to be about

as old as Lucy How can Lucy be a

missing link if

modern humanposture and gait werealready evolved?


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As I kneel beside thelarge print and lightly touch

its sole, I am filled with quietawe. It looks perfectlymodern. I thought that at

three and a half million

years ago their prints mightbe somehow different fromours, says Latimer. But

they arent. The bipedal

adaptation of thosehominids was full-blown. Gore, R. National Geographic, Feb.

1997


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Johanson insisted strongly that the Laetolifootprints 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 contentionthat the brain was too small to master tools.


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Problem:

The foot bones and lower leg of A. africanus(Lucy)have been recently found (in Hadar)

These foot and leg bones are apelike


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KNMER1470 found in 1972 with amodern 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 andover again until the best date was

placed at 2.61 Ma Lucy originallydated at 2.9 Ma

KNMER 1470 re-dated using BasilCooks pig teeth sequences to less than

2 Ma and Lucy to more than 3 Ma


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Richard Leakey, June of 1973, in an interviewwith National Geographic:

"Either we toss out the 1470 skull or we toss

out all our theories of early man. It simply fitsno previous models of human beginnings.1470 leaves in ruin the notion that all earlyfossils can be arranged in an orderly sequenceof evolutionary changes."


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Discovered in 1959 by Mary Leakey

Found with stone tools and evidenceof butchered animals

Given name of Handy Man or

Homo habilis supposedly evolvedafter/from Lucy (Australopithecines)

Does Zinj look at all like KNMER1470? (Both are Homo habilis) Fossil and living Coelacanths that were

given different genus and species namesyet look far more similar than Zinj andKNM-ER 1470 discussed in lecture on the Fossil Record


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Dr. Spoors research on semicircular canals ofH. erectus,

Australopithecus, and many other hominids indicates thatH. habilis, "relied less on bipedal behavior than theaustralopithecines." And yet, H. Habilisis supposed to bemore advanced than australopithecines?


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Leakey, 1990 PBS documentary:

If pressed about man's ancestry, I would have

to unequivocally say that all we have is a hugequestion mark. To date, there has been nothingfound to truthfully purport as a transitional specie to

man, including Lucy, since 1470 was as old andprobably older. If further pressed, I would have tostate that there is more evidence to suggest anabrupt arrival of man rather than a gradual process

of evolving.


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Matt Cartmill, Duke; David Pilbeam, Harvard; Glynn Isaac,Harvard, American Scientist, July-August 1986, p.419


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Neandertal (Neanderthal) Man (Homo neanderthalensis)

Thought to have died out over 20,000 years ago.

First found in 1856 in Neander Valley, Germany Johann Fahlrott (a school teacher)

Dozens of skeletons have since been found

In 1908, Professor Boule of The Institute of Human Paleontology inParis declared Neanderthal an ape-man because of his low eyebrowridges and the stooped over posture of some of the specimens


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Neanderthals had bigger brains (>200cc) Lived a long time (stooped by osteoarthritis)

Dr. Rudolph Virchow argued in 1872 thatNeanderthals were modern humans with ricketsand arthritis

The Chicago Field Museum has since put in anewer exhibition of Neanderthal man looking

more fully human Whats the latest scientific explanation?

Neanderthal man was an evolutionary dead-end


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What about DNA?

July 11, 1997, Neanderthal mitochondrial DNA(mtDNA) successfully recovered andsequenced by Svante Pbo et. al. (Cell) mtDNA recovered three times

Pbos Conclusion: Evolutionary divergence

from modern humans some 550,000 to 690,000years ago


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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 youand only 20 differences from a Neandertal

A human-chimp relationship might be closer than achimp-chimp relationship

Human-chimp difference might be only 46 while a chimpmight be 81 differences from another chimp


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Further confusion from Pbos article:

Neanderthal mtDNA was actuallyfarther away from chimp mtDNA thanthat of modern humans

We modern humans are therefore

more chimp-like than Neanderthals?!Or, within the range of ethnic variation?


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mtDNA as a Molecular Clock:

Recently called into question by articles inseveral 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 berevised to as young as 6,000 years old

(Parsons et al)


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A more recent 2007 study:

Comparisons suggest large differences: the

mutation rate estimated from pedigrees of humansis a hundredfold higher than the substitution ratefor the primate mitochondrial DNA control region. .. We await the more rigorous type of assessmentwith some nervousness, given that we suspect

they might reveal that many past studies placedtoo much confidence in simple molecular clockanalyses, and that their conclusions should thusbe revisited. Mario J.F. Pulquerio and Richard A. Nichols, Dates from the molecular

clock: how wrong can we be? Science Direct, Trends in Ecology andEvolution, Vol. 22, No. 4, 2007


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A mathematical model:

These analyses suggest that the genealogiesof all living humans overlap in remarkable waysin the recent past. In particular, the MRCA of allpresent-day humans lived just a few thousand

years ago [~3-4000 B.C.] in these models.Moreover, among all individuals living more thanjust a few thousand years earlier than theMRCA, 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, Nature431,Accepted 14, July 2004


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In 1937, Germaine Henri-

Martin, a very well respectedarcheologist, beganexcavations in a cave insouthwestern France

called Fontchevade andcontinued her work here until1954, removing over 900cubic meters of sediment

Discovered first Frenchmenolder than Neanderthals


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Many layers found

The topmost layers:"Aurignacian" (modern)

Underneath the Aurignacian:"Mousterian" layers, laiddown during the time of theNeandertals

Below the Mousterian:"Tayacian" layers withinwhich she found severalhuman skull fragments andevidence for the livingconditions of these firstFrenchmen


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Germaine found lots of evidence of how the first

Frenchmen lived The site is full of flint, which was interpreted as being

worked into tools

Various "hearths" were also found throughout the sitewhere the first families cooked, prepared their food,and ate

Evidence of meals, in the form of animal bones, wereeverywhere

Bones of the hominids themselves

The evidence for a rather complete an intricatelife for the earliest French people seemed ratherobvious and fairly easily interpreted


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In the 1970s Shannon McPherronand Harold Dibble decided to dosome reinvestigation

Laser mapped of thousands of stoneobjects and bones

Everything in the cave was orientedhorizontally or vertically with respectto the cave walls and there wasevidence of water sorting

The stone tools turned out to be nodifferent than naturally carved stones

Source of water found an openingat the back of the cave that drainedwater and sediments from above


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The narrator of the 2002 PBS documentary,"Neanderthals on Trial" concluded:

What made it look real to the archaeologists was anoverwhelming desire to see the past in a certain way.The urge to distance ourselves from Neanderthals or topull them closer to us is a surprisingly powerful force.Archaeologists Jean Philippe Rigaud and Jan Simekare well aware of the problem."

[Jan Simek added], "I think that we're as guilty of ittoday, of that kind of preconceived approach to our

data, as anybody has been in the history ofarchaeology or anthropology. It's almost inevitable thatour own views of the world will be brought to bear. . .


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. . . So it appears that Fontchevade was

an elaborate illusion and not a humanhabitation site at all. What made it look realto the archeologists was an overwhelming

desireto see the past in a certain way


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It is also interesting to considercomments made by the journalist,Mark Davis, who investigated this storyon Neanderthals for NOVA.

"I spoke with many Neanderthal experts in the course of makingthis film, and I found them all to be intelligent, friendly, well-educated people, dedicated to the highest principles of scientificinquiry. I also got the impression that each one thought the last oneI talked to was an idiot, if not an actual Neanderthal. . . The more

people I spoke with, the more confusing it got. . . Listening to thearcheologists and anthropologists talk about their work (and theircolleagues' work), I heard the same frustrations voiced again andagain: People are driven by their preconceptions. They see whatthey want to see. They find what they're looking for. . .


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. . . I learned that what people see in Neanderthalsoften has as much to do with philosophy as it doeswith science. What does it mean to be human? Somedefinitions are broad and inclusive, others are narrow

and exclusive. Scholars have been known to attackone another's views on Neanderthals as "racist" or"politically correct." . . .

What I found most interesting in all this is thatevery scientist I talked to encouraged me to explorethe issue of self-delusion, and no one claimed to be

immune. They are all aware that the history of thefield is littered with brilliant scholars who completelymissed the boat because of the power of theirpreconceptions."


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"A five million-year-old piece ofbone that was thought to be acollarbone of a humanlike creature is

actually part of a dolphin rib...The problem with a lot of

anthropologists is that they want somuch to find a hominid that any

scrap of bone becomes a hominidbone."

- Dr. Tim White(anthropologist, University ofCalifornia, Berkeley). Asquoted by Ian Anderson"Hominoid collarbone exposedas dolphin's rib", in NewScientist, 28 April 1983, p. 199


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3 feet tall with brain the size of agrapefruit - Bones discovered in a caveon Flores (Indonesian island) in 2003

Claimed to be a new species ofhuman due to unique features of theskull and a chimp-like wrist bonecompared to modern humans

The excavation work was partiallyfunded by the National GeographicSociety, which premiered a film aboutthe work March 10, 2008

Homo floresiensis


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Days later Lee Berger (U. of Witwatersrand inJohannesburg) published a find of least 26 other

individuals of similar size in caves on Microneasianislands.

Islands overrun by diminutive humans as recently

as 1,400 years ago - but despite their size these

people clearly belonged to our species. - i.e.,modern pygmies

As far as the chimp-like wrist bones, modern humanscan have a mutated gene (PCNT) that produces 3-4

ft stature, proportionate body size with normal ornear normal intelligence and bony wrist anomalies.

http://www.newscientist.com/article/dn13441-new-bones-suggest-hobbits-were-modern-pygmies.html?feedId=online-news_rss20http://www.telegraph.co.uk/scienceandtechnology/science/sciencenews/3320502/%27Hobbits%27-not-a-different-species,-say-scientists.html


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"The question that I and my colleagues haveasked ourselves is how anyone could possiblybelieve this, [that the hobbits are a new species ofhominids and not simply a modern ethnic humanvariation]. There was such a willto believe in thestory that critical faculties were suspended on thepart of many people.

Robert Eckardt at Pennsylvania State University, who co-authored the critique of the hobbit theory in theProceedings of the National Academy of Sciences.

http://www.guardian.co.uk/science/2006/aug/22/uknews


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F. Spoor, M. G. Leakey, P. N. Gathogo, F. H. Brown, S. C. Antn, I. McDougall, C. Kiarie, F. K. Manthi & L. N. Leake, Implicationsof new early Homofossils from Ileret, east of Lake Turkana, Kenya, Nature, Vol. 448 (7154), pp. 688 (August 9, 2007)


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Notice that it is ok to put this or that aspect of the theory of evolution tothe test as long as the overall theory itself is not questioned or

subject to potential falsification.

F. Spoor, M. G. Leakey, P. N. Gathogo, F. H. Brown, S. C. Antn, I. McDougall, C. Kiarie, F. K. Manthi & L. N.Leake, Implications of new early Homofossils from Ileret, east of Lake Turkana, Kenya, Nature, Vol. 448 (7154),pp. 688 (August 9, 2007)


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Humans, rats, and rice plants: Same number of genes

The key: Non-coding DNA formerly known as Junk DNA

Examples: microRNAs, Pyknons and pseudogenes

Indeed, what was damned as junk because it was not

understood may, in fact, turn out to be the very basis of humancomplexity, Mattick suggests. Pseudogenes, riboswitches and

all the rest aside, there is a good reason to suspect that is true.Active RNA, it is now coming out, helps to control the large-scalestructure of the chromosomes and some crucial chemicalmodifications to theman entirely different, epigenetic layer ofinformation in the genome.

Wyatt Gibbs, The Unseen Genome: Gems among the Junk,

Scientific American, November 2003, pp 45-53


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The different miRNA repertoire, as well as differences

in expression levels of conserved miRNAs, may contributeto gene expression differences observed in human andchimpanzee brain. . . For example, miRNAs recently havebeen implicated in synaptic development and in memoryformation. As the species specific miRNAs described here

are expressed in the brain, which is the most complextissue in the human body, with an estimated 10,000different cell types, these miRNAs could have a role inestablishing or maintaining cellular diversity and could

thereby contribute to the differences in human andchimpanzee brainfunction.

Berezikov et. al., Nature Genetics2006


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OliverOriginally capturedin the 1960s from

the African Congo.

Thought, even byscientists, to be apossible human-chimp hybrid.


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M ti t h


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My reservations concern not so muchthis book but the whole subject andmethodology of paleoanthropology. But

introductory books - or book reviews - arehardly the place to argue that perhapsgenerations of students of humanevolution, including myself, have beenflailing about in the dark: that our data

base is too sparse, too slippery, for it to beable to mold our theories. Rather thetheories are more statements about usand ideology than about the past.

Paleoanthropology reveals more abouthow humans view themselves than it doesabout how humans came about. But thatis heresy.

Dr. David Pilbeam, ananthropologist fromHarvard, making some veryinteresting comments in a1978 review of RichardLeakey's book, Origins


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lecture 1 - early man

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