U.S. flag

An official website of the United States government

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Madame Curie Bioscience Database [Internet]. Austin (TX): Landes Bioscience; 2000-2013.

Cover of Madame Curie Bioscience Database

Madame Curie Bioscience Database [Internet].

Show details

On the Evolution of Humans


Ancient bones are somewhat like wind vanes that show from which direction a particular hypothesis breezes across the fossil field. If a paradigm is useful one should be able to predict what will be found at the end of the projected course. This means that one can put a general evolutionary hypothesis like a grid over the pattern of evidence and see how fossils and expectations match. In the standard model predictions are not possible because the phenotype lattice radiates from one spot (the common ancestor) with every beam studded with chance-initiated branch points that give rise to unpredictable patterns.1 By rules of the Genomic Potential Hypothesis the future position of a species in the hierarchy of taxa is, in principle, predictable. The discussion of our own past will reflect this fundamental change in philosophy.

The human brain is monstrous even if compared to our closest competitor, the great ape, but our truly unique property is the physiological (as opposed to habitual) upright walk which includes special anatomical features such as a narrow pelvis, the slightly inward-directed thigh bones, and plantigrade feet.2,3 Upright-walking species show a foramen occipitalae at the base of the skull rather than the posterior aspect. These are unmistakable markers that are readily recognized in the fossilized form. Anthropologists will always be looking for ancestors that do not show these features because the old school says that the upright walk developed slowly from a quadruped animal by gene duplication and mutations. That proposal is of beguiling simplicity if one forgets the biology and biochemistry required for that transition. Looking back in time one is faced with the fact that the brain had all but disappeared at Lucy's (A. afarensis) developmental stage, yet she was fully bipedal.4 To find the presumed quadruped ancestor would lead to insurmountable identification problems unless, as shown in a cartoon by an unknown artist, step-less melting of one form into the other can be observed.

Large brains relative to body-size are always associated with bipedality whereas bipedality is not invariably associated with large brains. Once a chimpanzee-brained creature has the features of upright walk it becomes a hominid, and when that hominid acquires cranial features that suggest a larger brain and when artifacts are found next to the fossils, it becomes a member of our genus Homo. Did the apes change, as in the old model, or was a new species introduced, as the Genomic Potential Hypothesis predicts? (see Fig. 1)

Figure 1. In this figure the requirements for establishing a smooth transition between species is depicted.

Figure 1

In this figure the requirements for establishing a smooth transition between species is depicted. While this example from an unknown artist is meant to amuse the viewer, it is precisely what Darwinian language projects when he speaks about the “inconceivably (more...)

The experts think of slow transitions but their own evidence says replacements. The analysis of a nearly complete skeleton found in the Afar Valley of Ethiopia told Johanson and his colleague that A. afarensis was a true upright walker with a brain about as large as that of a chimpanzee.4 More than 10 years after this sensational discovery that destroyed the “brain first” idea, Johanson and his colleagues returned to the fossil hunt, this time in the Olduvai Gorge. He found a specimen that is, in my opinion, equally sensational because the creature was as small as Lucy, but lived about 1.8 million years ago compared to Lucy's ∼3.3 million years.5 The skeleton had very similar features but the brain case was large enough to earn its owner membership in the homo family as H. habilis. There was a gap of 1.5 million years between A. afarensis and H. habilis which seemed to have resulted in a slight increase in brain volume but, remarkably, no other changes. A quote from the source of that information may help to illustrate this point for all its importance.

“If body height in the human line did indeed increase gradually from afarensis to erectus, then by heights Homo habilis should have averaged somewhere between four and a half and five feet tall. Instead, we had found a habilis skeleton that appeared to have stood no taller in life than Lucy herself. Judging from the fragments we had of the Dik-dik Hill hominid, from the neck down she was practically Lucy's twin.”.6

This result was baffling since an almost contemporary of H. habilis, the 1.6 million-year-old nearly complete skeleton of the 5'4"-tall “Turkana” boy had been found who was a member of a species called H. erectus.7 This species had modern body proportions and significant mental capacity as signified by the fine Acheulean tools found near the fossils.5 A new, more advanced species had appeared from nowhere!? Johanson made the following revealing statement:

“We already knew that Homo erectus' brains were significantly bigger than those of H. habilis -----and now it seemed evident that their bodies were qualitatively different too”.6

He left the ends hanging, but the message rings clear: whenever it was possible to follow a species for any length of time, very limited changes would be observed until elsewhere, in about the same layers, a more advanced species showed up! In all cases has it been impossible to establish unique connections to the purported ancestor in the hypothetical line-up of hominids. That is precisely what the genomist predicts, i.e., species do not branch, they develop, each from a specific pro-form within a million years or so, rapidly enough that only the nearly final stage enters our fossil archives. Everyone in evolution knows this scenario and accepts it as a conditional Darwinian event, confident that the intermediate forms required for credibility will show up in due time.

By the same reasoning one cannot be sure that any particular bipedal creature, say A. anamensis, A. afarensis, H. habilis, or even H. erectus would be in H. sapiens' ancestral line. There is no set of intermediates to make that point and without these intermediates the Genomic Potential Hypothesis explanation should be considered. Accordingly, hominids came in waves from independent clones, rapidly proceeding through the hypothetical initial spurt stages until they were large enough to leave identifiable fossils, likely smaller than the ultimate form. Finally, starting less then a million years ago, the brainy clones went through their juvenile forms to appear as H. neanderthalensis and H. sapiens. And again we read about these remarkable overlaps such as the coexistence of H. erectus and modern humans on the island of Java,8 the well-documented overlap of H. sapiens neanderthalensis and H. sapiens sapiens in the Middle East.9 Overlaps per se do not exclude branching, but when the fossils in question are as recent as A. afarensis, H. erectus, and H. habilis or even more recent, H. sapiens sapiens and H. sapiens neaderthalesis, the actual branching event lies so close that one should easily find the fossils. The rewards of finding branching points would have been very great indeed and an intense search to reach that goal is in progress. The fact that anthropologists have been unsuccessful weighs heavily against the branching scenario.

This view brings us onto a collision course, although it provides a more plausible place for Johanson's Lucy and her daughter than the old model. It is considered more significant to find a human ancestor than merely another biped that hit the stage prematurely so that usually every effort is made to make that human connection. To the uninvolved observer the evidence suggests that A. afarensis (Lucy) lived from about 4 million years ago until 1.8 million years ago and might have developed into H. habilis before extinction. At that time H. erectus had grown to the size of modern humans and persisted as H. erectus until he too met both, a newcomer H. sapiens and extinction. This I believe to be the essence of the story as concerns evolution. Anthropologists are quite rough with each other about the details and we have no reason to get involved. The information that seems to be fairly secure is that intermediates between the various hominids have not been observed. The evidence that has accumulated until now suggests that the biped physique appeared abruptly about 5 million years ago in Africa and that upright walkers that came later also came with the potential for larger skulls.

The “out of Africa” idea of human evolution is dominant among anthropologists perhaps because most fossils were found there, because of the commitment to a single origin scenario, and finally because of cultural demands that all humans be of equal descent. In the final analysis these are not very forceful reasons. The African desert may be just more accessible and provide for better preservation of bones. The old paradigm, however, is so strong as to merely allow discussions concerning migratory routes when fossils are found elsewhere; multiple origins are almost never considered. For the genomist there are good reasons why humans should have become visible in many places within the same time frame. Nevertheless, the “African origin” arguments will be resolved when human remains of such age are found in, say China or Australia10,11that only air transport could have brought them from Africa in time to show up in the same horizons. As one looks into earlier layers the origin of these hominids should be discovered. The fossil record of other species reaches up to hundred times further into the past so one might reasonably expect to see the predecessors of bipeds at least into the Eocene (∼50 million years) together with the bones of horses? But we do not! Bipedal creatures disappear from our view not by melting into the contours of a different animal but rather by fading out, i.e., by getting smaller rapidly and then disappearing. The genomic potential model suggests that the forms melt into a specific pool of primary stem cells and that these stages will be recognized once a mental image has been formed as to what to expect. Note that germinal forms of Cambrian animals, which the new hypothesis predicts to exist, may well have been seen already.12,13

Nobody has intentionally looked for germinal forms of large animals or humans whereas everybody has looked for intermediates. A straightforward reading of the evidence produced by over 100 years worth of anthropologists' efforts to find them has failed. The selection of acceptable interpretations is very limited when a species, clearly marked in the fossil record, suddenly disappears as one proceeds into lower horizons while other animal fossils persist undiminished in the same layers. Either the species emerged at once from parents of a very different kind (the “motley egg” hypothesis), or it did what species had to do when there was no macroscopic ancestor around, i.e., emerge from a species-specific primary “stem cell” that had developed during the Precambrian. This is the metamorphic event postulated by the Genomic Potential Hypothesis which stresses credulity because it is counter-intuitive. A ‘caterpillar’ in the ancestry of all animals, including humans, is a tall order even for the most propitious of readers, so let me take time out to bring the problem into perspective because it is as crucial for human evolution as it is for all other species.

All eggs and seeds are sensu stricto metamorphic stages. Birds, amphibians, reptiles, and even some mammals have external eggs from which, after a period of incubation (development) the juvenile form of the species emanates with just the cracking of a shell. Insects go through this stage as well but, in this case, the first stage is another “egg”, a caterpillar, a moving, feeding egg that increases the energy reserves and then wraps itself into a cocoon from which in due time the amazing color stencils of butterfly wings emerge. Two completely different body plans, different locomotion, and different feeding patterns produced not slowly by mutations and adaptations, but read from the genome in abrupt stages from one start. Had this mode of propagation gone extinct about ten thousand years ago, and even if we would be able to see butterflies preserved in a fine-grained shale, the connection to caterpillars and pupae would never have come to light without a hypothesis to that effect. Experts, driven by the old model, would keep looking for the oldest possible butterfly and beyond that, for a fly or a flightless bug, as they actually do,14 that could have been converted by sunlight and an avalanche of gene duplications and mutations into a butterfly.

Secondary ova, those that were produced by a finished prehistoric animal, have been found frequently, and when dinosaur eggs revealed the fully formed embryo there was no doubt about the saurian way of reproduction.15 Precambrian eggs have been found16 but never one of the primary eggs, which must have been there en mass for each species a few thousand years before the entry of a species into the fossil record. Until now, there was no good reason to look for them and, of course, there is no handbook for identification purposes. Certainly the avalanche of exquisite fossils from China, which is pushing the age of vertebrates deeper into the Cambrian, will provide an excellent chance to find some of the pro-forms postulated by the Genomic Potential Hypothesis.17

When did these primary ova give rise to the first metazoan with human potential? The fossil record suggests that it might have been between 5 and 3 million years ago. It is true that several clones of primate quadrupeds (early ape-like creatures) began to appear about 15 million years ago. They have colorful names like Ramapithicus africanus, Sivapithicus africanus, Kenyapithicus africanus, Kenyapithicus werteri and Proconsul africanus, to name a few. Within the logical framework of the Genomic Potential Hypothesis it seems that this group represents an isolated eruption of ape-like creatures, which do not connect to modern apes or humans other than to foreshadow the arrival of higher primates. This view appears to be shared by at least some anthropologists.18 The early record of non-human primates seems to be interrupted for a period beginning about 8 - and ending 5 million years ago when modern ape fossils left their marks slightly ahead of the first hominids (upright walkers, 4.5 to 3.5 million years ago). This was the time at which A. afarensis (Lucy) lived who literally rose from the dust in 1974 with significant help from Johanson and White.4 While hominid skulls and bones had been found by other anthropologists, the Leakey family comes to mind, which were named australopithicines (southern apes), no leg bones or pelves of such age had been seen from one individual before Lucy.19 Lucy came as a shock to anthropologists because her knee bones, her feet, and pelvis showed clearly a fully finished upright walker, but her skull was as small as that of a chimpanzee. Lucy was not terribly popular among students of evolution, the “brain-first” paradigm lain in shambles at her feet (she would have known that it is better to be infamous than ignored). It was Lucy's “hypothe-cidal” quality that drove the fiercely competitive and secretive stars among fossil hunters back to the fossiliferous grounds in Africa to see what came before her. As a consequence Lucy got an ancestor called A. anamensis,20 who was bipedal and lived between 3.9 and 4.2 million years ago. More appear to be rising from the parched landscape of Ethiopia that could extend bipedality to 4.4 million years when the official entry for A. ramidus is made.21 That is where we are, skin deep into the history of life. The large skull has long been lost on our travels into the past but the upright gait is persisting. This reality points to another conceptual difficulty inherent in the search for transitional forms that lead from animal X to hominids. Once the brain is lost as well as the upright gait there remains no identifier that would tell us that the suspected ancestor is not a member of one of an extinct species of prosimians, for example. A speciation fork is unprovable unless two paleontologists, each following a different fossil into the past, will meet at the same fossils in a lower formation to claim it as the ancestor for his species. The new hypothesis demands that fossils never meet so that the two observers, starting with different fossils, will never see each other again. Figure 2 shows the world lines of early and recent primates dangling into the past, disconnected from the pools of Darwinian ancestors and reattached to the primary ova of the Genomic Potential Hypothesis.

Figure 2. This is a take-off on a figure by paleontologists concerning the evolution of nonhuman primates and hominids.

Figure 2

This is a take-off on a figure by paleontologists concerning the evolution of nonhuman primates and hominids. The world lines of species from the Genomic Potential Hypothesis were added to the figure. Beginning in a circular region at the bottom which (more...)

There is no sign of a transition from quadruped to biped or from ape brain to the larger brains of hominids. Fossils of small and large brain cases show up side by side until one group disappears while the other continues the relay.

One might ask, for instance, what happened to the apes during the past 5 million years? Nothing changed in any remarkable way other than an increase in size. They could have developed brain, but it was not in their genes. The conditions for Darwinian selective pressure were definitely there. A quadruped with a larger brain would have done substantially better than one with an ape brain. It would have helped them to avoid a future life in zoos and the cages of their experimenting “cousins”. Victims of an unmodifiable genome, modern apes merely watched how A. afarensis raised their young in that awkward upright position (equally without a choice). The robust australopithicines in turn watched a larger-brained upright walker called H. habilis for a while, and possibly had him for dinner off and on, because H. habilis was somewhat smaller, before both headed for extinction (not adaptation). It must have been a strange experience for H. erectus to meet the first of H. sapiens as they apparently did on the island of Java and possibly elsewhere.22

The fact of the matter remains that nearly all of those elevated retroactively to the status of human ancestor lived together for part of the time of their existence. They materialized in our records from splinters a little larger than dust specks, one outline after another, brought into full view by the skills of anthropologists, as more lined up as outlines in the distance. But there is insufficient evidence to line them up in a bona fide chain of ancestors, they were most likely covivants on earth.

The main story leads us to two brain centers, both appeared between 500,000 and 200,000 years ago, one known as Homo sapiens neanderthalensis and the other as Homo sapiens sapiens. The brain was large in relation to body size with Neanderthales enjoying an edge of a few cm3 over sapiens. From there on the development of more potent brains was a matter of selection and breeding, the size of brains remained fairly constant once H. sapiens was recognized in its earliest forms. Even today the brain power of individual humans varies by orders of magnitude, but the extremes of humans and apes do not nearly overlap in spite of what we at times contend about each other.

For the time being A. afarensis or possibly A. anamensis are the first upright walkers, our preludes sensu lato. Questions seeded by the Genomic Potential Hypothesis pertain to the path between any of the first bipeds and their corresponding primary stem cells. How would this transformation look in a real world that had predators lurking behind every spade of green? Could one expect a millimeter size upright walker to exist and to fend for itself at a time when every legitimate grub or insect would be elephantine by comparison?

It is likely that they went through survival stages, moving, feeding larvae, protozoan, fungi23 or different durable creatures of that size and would not transform into much larger organisms until, at the end, a genetic upright walker would crawl away on hands and short legs from the last metamorphic event while the genomic potential would drive its size up to the point where it could assume the physiological upright position and remain alive in a competitive world. The same had happened at different times for A. afarensis, for the other australopithicines, for H. habilis, H. erectus and so on, for many groups that we have yet to discover. If this thought is uncomfortable it is so only because we did not grow up with it and because our self-esteem has provided for a more grandiose scenario.

One must view the new proposal against what has been accepted so far. Many, if not most, Darwinians are often unaware of the details of their model. Here is a short version of it.

Looking back from our branch in the traditional tree of life, right at our feet, we see several lines of hominids and, close by, the great apes. Further down lemurs and tree shrews may have carried our genomic torch, but as the deep Tertiary is left behind the choices become limited. A nondescript mammal in the form of a small saurian comes to mind, a hairy reptile has been mentioned in the Cretaceous and perhaps a reptile in the Jurassic. In the Devonian the Darwinian life becomes waterlogged, leaving us fishes, brachiopod-type clams, or worms like priapulids as potential banner bearers for the pro-human genome. This would get us through the Ordovician and the Cambrian and perhaps into a Precambrian where sponges were found in the 650 million year old phosphate deposits in eastern China and central Russia.24 Now, we are passing through 3 billion years of single cellularity, until we end up within the cubic micron confines of the single cell that started it all. This conjures up images of the one microscopic cell on this earth as seen from an airplane window, and that is the point where the old idea moves into the proper perspective. On this time-reversed trip to this cell we crossed kingdoms, phyla, classes, families, and species, with only one recurrent explanation, i. e., random mutations. It is not the nightmarishly difficult concept that makes this model impossible but rather the lack of contiguity that enters the paradigm with every “constructive” mutation (see Chapter 2).

The precedence argument may help to clarify, if not resolve the issue of evolutionary routes. The Cambrian has given the stamp of reality to the transition from single- to multi-cellularity. There were only calcareous microfossils in the antecedent Tomotian, but there were masses of arthropods in the mid-Cambrian! That would mean that different, to us invisible life forms, had undergone transformation into arthropods! Thousands of transformations, one for each member of each species, had occurred according to the Genomic Potential Hypothesis. In the Darwinian model it was one for all metazoan, followed by descent with variations, a mechanism for which the time was too short. We have visited this scene before (Chapter 7); it is a crucial one and it tells us that the current model of evolution is dogmatic in the face of contrary evidence. The new model predicts the simultaneous appearance of groups of animals in successive intervals such that one does not need to invent new mechanisms for every animal; it is the same type of transition occurring a little sooner and a little later (by geological standards).

While the new hypothesis depends upon the observations that intermediates between species are missing, the uncertainty about our germinal stages remains until one finds the metamorphic state frozen at the moment of conversion to a phenotype in the late Quaternary sediments. Science, at our present state of development, leaves us no alternative.

As surely as intermediates between species are nonexistent, the intermediates between the primary ovum and the first stable fossilized creature are there for us to discover. They will be in the same horizon, only a few thousand years or less apart.Fig. 3 gives the impression that all species had been washed into the present by a powerful wave so that the times of arrival are only minutely different. The time axis gives one a realistic impression of the awesome speed of appearance of species when compared to the total time of life on earth. The whole colorful world of anthropology that reverberates from fierce battles over what is a common ancestor, what limb should be attached where on which evolutionary tree, all of that fits into a little more than the width of the line frame that separates past and present in Fig. 3. To an uninvolved observer the intensity of the dispute about the common ancestor means that none has been found. The Darwinian hypothesis pours fuel into the flames by insisting that there is a common ancestor and if they look long enough they will find it. The new hypothesis is kind to its followers, it provides a unique first ancestor for each of the hominids.

Figure 3. This drawing transmits a realistic concept of the time of development of metazoa as a function of the total biogenic time on earth.

Figure 3

This drawing transmits a realistic concept of the time of development of metazoa as a function of the total biogenic time on earth. Notice how short the distance is between a jellyfish and a human and how little time there was in the old model to convert (more...)

In the next figure the scale has been expanded to show how the transition to phenotypes can be anchored to indisputable events which, together with the absence of intermediates between animals, forms the foundation for major predictions derived from the Genomic Potential Hypothesis. Reference is made to the precipitous appearance of arthropods during the mid-Cambrian period right on the edge of the microfossil-producing Tommotian age. There is no identifiable macro-organismic precursor so that here the Darwinian chain of descent with variation is forcefully interrupted. The process must be continuous, however, and the only explanation left is metamorphosis. The implications are presented in Fig. 4. The ‘violin keys’ designate the approximate time when the conversion of stem cell clones began to produce ‘metamorphs’ in large numbers within a period of time of which many persisted to fill the ranks of families, superfamilies, a process that may be a target for future research.

Figure 4. In this figure the time of metazoan development has been expanded in relation to the total biogenic period in order to provide space to show where the metamorphic processes might have occurred which, followed by a rapid spurt of development, led to groups of somewhat similar species that we group today as order, suborder, genus and species.

Figure 4

In this figure the time of metazoan development has been expanded in relation to the total biogenic period in order to provide space to show where the metamorphic processes might have occurred which, followed by a rapid spurt of development, led to groups (more...)

The Cambrian arthropods start the series and because, as mentioned above, there were no macroscopic ancestors that could have been converted slowly by mutation and adaptation to the first animals in the shale, they set the tone for the evolutionary calendar of events. There are no recognizable intermediates leading to fishes, would it not follow that they too should have evolved by the same route that brought about arthropods? The step from fishes to amphibians is informative. Coelacanth and its purported successor Ichthyostega are contemporaries. Would that not suggest quite forcefully that both came about by the same mechanism? And the mammal is a little further along and so on. The answer must be the same for all these cases until humans came along, and there is no evidence that would compel us to use a different explanation for our evolution. This model again leads to predictions as discussed in the context of the next figure where the scale has been extended to make our history visible.

The arrows in Fig. 5 show the time of the purported metamorphic event and the triangles show the point during development when the species should be anatomically distinct, albeit smaller than the final form. The scale for hominid evolution has been expanded such as to include only the last 5 million years, i.e., 0.15% of the total biological eon on earth! Most readers will find the implications of this figure deeply disturbing because our place in the evolutionary tree had become part of our culture. The view from the tree top was great and besides that, we have lost all our “inferiors”. But how could one exempt humans, by what contiguous scheme could we make ourselves different? All autonomic human functions are not better (sometimes less efficient) than in an animal. Of course, we are outstanding as concerns the central nervous system but it is not unique, it is merely more of one thing and perhaps differently folded. Within the framework of the Genomic Potential Hypothesis we are fitting perfectly well into the scheme of things.

Figure 5. Gives an even more expanded view of the last 5,000,000 years, the time of homonids.

Figure 5

Gives an even more expanded view of the last 5,000,000 years, the time of homonids. At this scale one sees distinct differences, for example, between the origin of A. afarensis and the time when it became visible (arrow points) until extinction. Notice (more...)

This is the point where the hypothesizer clears the field for the experimenter. If the series ‘caterpillar-pupa-moth’ would have to be extracted from the fossil record perhaps we could get the evidence today because we know that it happened as surely as we know that the caterpillar did not go through descent with variations to become a butterfly. Perhaps with a new attitude we may be able to find our developmental pro-form in the lower Quaternary layers. Metamorphosis teaches that the gene is important for what an animal looks like, and when one can accept this lesson then one can make peace with a fossil record that does not want to produce the intermediates that everybody is looking for.

There is our edifice of concepts, beautiful and a little aloof. Looking from the balcony into the street we can see anthropologists still arguing that Lucy was not quite the upright striding creature that the discoverers made her out to be, but that her gait still had a twist of “intermediate ” quality to it. Then we see Mary Leaky with the Laetolil footprints of A. afarensis' contemporaries, which marked the ground, measure for measure the way we would, and even then the old hypothesis would not give up. What is the point? Lucy killed a bad idea, which is commendable; she never changed into anything else. She was likely not our ancestor but rather one of the group of upright-walkers that ran parallel and a little ahead of H. sapiens. She shared with us the gait but not the brain. One that shared both, the Neanderthal, came a little ahead of us. The last 150, 000 years we lived together, trading and alternately occupying caves in the Middle East22 and recently even sharing the front cover of the Scientific American under the title “Once we were not alone”.9 What makes me chuckle at the sight of such politically correct display is the fact that between existing branches of H. sapiens (to which Neanderthal belonged) the artist could have found significantly larger differences than those he chose (dared) to display. So why are we alone? Because we say so, that's all. In our enlightened age we cannot separate science and politics. The reader may remember my introductory remarks about the amalgamation of science and culture and correctness.

To do science properly one has to be willing to be politically incorrect. This building of mine is politically incorrect (apolitical in fact), but it is esthetic and elevating to the free spirit, and some day evolutionists will look into it and suffer an attack of deja vu and then our theoretical excursions will acquire a different glow and likely a new owner to boot. Chemistry is Machiavellian.

Darwin is often accused of having never dealt with the origin of species other than in the title of his book. The Genomic Potential Hypothesis tells why he could not have come any closer then he did and history will recognize that he picked the only non-divine choice left under the circumstances, the breeding of one species from another by infinitely extended animal husbandry. Science was not ready to provide the limits for that approach; science was not ready for Darwin.


Gould SJ. The persistence of natural philosophy. Evolution and the triumph of homology, or why history matters. American Scientist. 1986;74:59.
Lovejoy CO. Evolution of human walking. Scientific American. 1988:118. [PubMed: 3212438]
Crelin ES. The development of the human foot as a resume of its evolution. Foot Ankle. 1983;3:305. [PubMed: 6873776]
Johanson D, Edey M. Lucy 1981. Simon and Schuster, New York;
Johanson DC, Masao FT, Eck GG. et al. New partial skeleton of Homo habilis from Olduvai Gorge, Tanzania. Nature. 1987;327:205. [PubMed: 3106831]
Johanson D, Shreeve J. Lucy's Child William Morrow & Co. Inc. New York. 1989.
Brown F, Harris J, Leakey R. et al. Early Homo erectus skeleton from west Lake Turkana, Kenya. Nature. 1985;316:788. [PubMed: 3929141]
Swisher III CC, Curtis GH, Getty J A G. et al. Age of the earliest known hominids in Java, Indonesia. Science. 1994;263:1118. [PubMed: 8108729]
Tattersall I. Once we were not alone. Scientific American. 2000 Jan:56–62.
Thorne AG, Wolpoff MH. The multiregional evolution of humans. Scientific American. 1992:76. [PubMed: 1566033]
Wolpoff MH, Hawks J, Frayer DW. et al. Modern human ancestry at the peripheries: a test of the replacement theory. Science. 2001;291:293. [PubMed: 11209077]
Pratt BR, Zhang X -G. Unscrambling fossilized Cambrian embryos. J of NIH Research. 1995;7:46.
Bengtson S, Zhao Y. Fossilized metazoan embryos from the earliest Cambrian. Science. 1997;277:1645.
Gould SJ. Bully for Brontosaurus W. W. Norton & Co., New York. 1991.
Morell V. Follilized hatchling heats up the bird-dinosaur debate. Science. 1997;276:1501.
Chen J -Y, Oliveri P, Li C -W. et al. Precambrian animal diversity: Putative phosphatized embryos from Doushantuo Formation of China. Proc Natl Acad Sci USA. 2000;97:4457. [PMC free article: PMC18256] [PubMed: 10781044]
Stokstad E. Exquisite Chinese fossils add new pages to book of life. Science. 2001;291:232. [PubMed: 11253830]
Pilbeam D. The descent of hominoids and hominids. Scientific American. 1984:84. [PubMed: 6422549]
Leakey L S B, Tobias PV, Napier JR. A new species of the genus homo from Olduvai Gorge. Nature. 1964;202:7. [PubMed: 14166722]
Leakey MG, Feibel CS, Mcdougall I. et al. New specimens and conformation of an early age for Australopithecus anamensis. Nature. 1998;393:62. [PubMed: 9590689]
White TD, Suva G, Asfaw B. Australopithecus ramidus, a new species of early hominid from Aramis, Ethiopia. Nature. 1994;371:306–312. [PubMed: 8090200]
Swisher III C. et al. Latest Homo erectus of Java: Potential contemporaneity with Homo sapiens in southeast asia. Science. 1996;274:1870. [PubMed: 8943192]
Redecker D, Kodner R, Graham LE. Glomalean fungi from the Ordovician. Science. 2000;289:1920. [PubMed: 10988069]
Li C -W, Chen Y -J, Hua T -E. Precambrian sponges with cellular structures. Science. 272;279:879. [PubMed: 9452391]
Copyright © 2000-2013, Landes Bioscience.
Bookshelf ID: NBK6367


Related information

  • PMC
    PubMed Central citations
  • PubMed
    Links to PubMed

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...