Earthlings (documentary) - Page 8

Why would we want to...?

And I think there are issues there that no current human society can deal with. Best to leave it alone.

Fatuous questions regarding the composition of the current President of the US aside (sorry, couldn't resist) even the mere suggestion of creating such a chimera would be enough to stir science-fearing religious fundamentalists into a frenzy, and perhaps for once their indignation would be justified.

Assuming the technical difficulties of incompatible chromosome counts etc could be overcome (and given time I have little doubt that they could) what would the purpose of such an exercise be? Simply to see if it was possible? Creating new cells lines in the lab by mixing genes from different species already has enough ethical question marks hanging over it. The creation of a young "Humanzee" carries with it the rather more obvious question...what would life be like for such a creature?

Not very pleasant would be my guess.

As Steal City has said, it could probably be done but what would be the point? The humanzees would only end up taking over the world and using humans as slaves in a post-apocalyptic society.

It was done about 60 years ago the result was george bush

On February 24 2009 12:11 Steal City wrote: It was done about 60 years ago the result was george bush

So we make one Humanzee and he ends up president of the United States?! crap, we best not create any more, dumb and powerful is not a good combination!

On February 24 2009 12:06 genjix wrote: Short answer. Ethics aside, we cannot due to a differing chromosome count. Our chromosome 2 is actually a fusion between 2 chromosomes from our shared ancestor. Unless we can artificially split and restructure our number 2 or alternatively artificially fuse the corresponding chromosomes in a chimp.

Your short answer is wrong. Horses and donkeys don't have the same number of chromosomes either. Differing chromosome numbers is not a barrier to hybridisation. There are even species where chromosome numbers differ within a population.

I think the clinching argument is that it would not teach us anything. The creature (for once, this term seems appropriate) would not be like any one of our pre-human or early-human ancestors. So the attempt would not only be ethically atrocious (which, being a philosophical point of view, is always debatable) but also scientifically pointless, which is not debatable.

On February 24 2009 12:13 Steal City wrote: I think the clinching argument is that it would not teach us anything. The creature (for once, this term seems appropriate) would not be like any one of our pre-human or early-human ancestors. So the attempt would not only be ethically atrocious (which, being a philosophical point of view, is always debatable) but also scientifically pointless, which is not debatable.

There is no way of possibly knowing what it could teach us, as a technical exercise it would at least teach us how to create human/chimp hybrids. Overcoming the pitfalls in the process would no doubt give us a greater understanding of the human genome. While the technical knowledge gained just by merely attempting it does not justify attempting it, it does prove that whether or not it is scientifically pointless is in fact debatable.

Also although just creating a human/chimp hybrid would not create anything resembling a common ancestor who is to say the entire genome of a common ancestor isn't contained the amalgamation of all the living descendants (well obviously a mathematician could give you the statistical probability of that hypothesis) but I am going to put it out there as a topic of discussion. If that is possible then only common ancestors with a large variety of living descendants would be possible to recreate. ie it would be impossible to create Theropod dinosaurs because all the living ancestors have a more recent common ancestors (presumably the earliest possible would be the first bird with a beak as that is the last thing birds evolved which is common to all birds). But perhaps it could be possible to recreate the earliest amphibians by the amalgamation of nearly every living land animal in existence. (although I severely doubt that)

Also I believe that inevitabley some one will do this somewhere, and while this is not worth pouring research money into which could be better spent. Curiosity is as good a reason as any for it to be attempted. Besides I am sure most of you wouldn't have the same hangups about creating a other animal hybrids.

My few cents on this matter.

I think a healthy human chimp is possible since the hybrid animals we have already bred would appear to be healthy, but I have no information to back that up offhand. Humans and chimps diverged 3MYa ago. Apart from bulk genome structure differences, viability would probably also be a function of divergence time.

Most people seem to think that we inevitably have to proceed with fertilisation to the result of an a humanzee individual. But that is not so - we could learn considerable amounts just by studying the early embryo and perhaps creating a stem cell line from it. No talk about creating hybrid individuals is needed.

As for the ethical concerns...these would be, in part, addressed by assessing that early and later embryos are viable and healthy. Our knowledge based on other hybrids would seem to support the idea that even if you were to permit a hybrid to grow to an adult, we would not encounter any nasty surprises for it, such as some bizarre illness. A humanzee would almost certainly be sterile too, which eliminates the concern over chimp genes entering the human gene pool.

An important ethical question might be what rights would be extended to an artificially-created humanzee, and given its relationship to humans, would this be ethical. Everyone immediately balks at the idea of human-greater ape hybrids but few can put their finger on it. I fall back on sci-fi here, since science fiction seems to be the best predictor of what we allow to be done with science creates for us in the future. If we were to create human-chimp hybrids on a large scale and use them as research animals, servants or manual labour and treat them as second class citizens as in Planet of The Apes, that would be very wrong indeed.

you are really posting all these because Loco derailed your thread aren't you Steal City?

Well, the purpose of my suggestion was to make some people more aware that, while humans are special, we are not THAT special. We're just a species of talking primates, a funny branch on the tree of evolution.

While we could take proper care of the humanzee (after all, we do take proper care of the hapless who were born with insufficient mental capacity to live their own life, at least in some countries), I believe the point would already be made if the foetus reached 3 months. Or perhaps even a fertilized egg that developed beyond a certain stage could get the point through.

This is actually a subject I've thought about and researched for several years now. I have an unfinished screenplay on the back burner, waiting for some inspiration to finish it up, but as many people have already said, they think such an experiment would be unethical or pointless...

My avatar picture was taken from the following video, which is about a white chimp whose eyes are different than other chimps. One eye is blue and the other is brown. Both eyes have white around them, which is rare enough to make one question how such a mutation happened, and it gives a more human-like appearance to the chimps face.



Make of it what you will... :shock:

To get an idea of the feasibility of the humanzee, I've been trying to dig up some date on the common ancestors for donkey/horse and tiger/lion. If they are longer ago than the human/chimp common ancestor split (believed to be about 5 mio years ago), the idea might be feasible.

For horses/donkeys things look promising:
1) Since horses, asses, and zebras, whose evolutionary divergence is relatively recent, show remarkable morphological similarity and capacity to interbreed despite their chromosomes differing considerably ... we compared the centromere position and marker order arrangement among orthologous chromosomes of Burchelli's zebra (Equus burchelli), donkey (Equus asinus), and horse (Equus caballus). Surprisingly, at least eight CRs took place during the evolution of this genus. Even more surprisingly, five cases of CR (Centromere repositioning) have occurred in the donkey after its divergence from zebra

2) How donkey and horse karyotypes gathered these differences within a short period of 5-10 Myr since divergence from a common ancestor will be known only after an ancestral equid karyotype is deduced, and the direction of change leading to chromosome rearrangements is clearly understood.


For Tigers and Lions the divergence is apparently less than that of the human/chimp split, so no positive pointer that the humanzee might be possible. I came across a site where they made mention of 2 mio old fossils clearly recognizable as Tiger, so I guess that is about how old as it gets. Perhaps the fact that humans and chimps tend to live longer on average might be a comforting factor.
3) The tiger cymtDNA shared around 90% sequence identity with the homologous numt sequence, suggesting an origin for the Panthera numt at around 3.5 million years ago, prior to the radiation of the five extant Panthera species.

The links for the sources are below.

1) http://www.sciencedirect.com/science?_o ... bc4832b123

2) http://content.karger.com/ProdukteDB/pr ... tNr=224037

3) http://www.sciencedirect.com/science?_o ... f30b82a359

If I may be so bold, I suggest that the label "aquatic ape theory" for a thread title is not quite right for a discussion of the influences of moving through water may have had on ape-human divergence.

The fact is "the" theory is not one, but several.

Here are some...

Westernhofer's (1942) "Aquatile" hypothesis published in "Das Eigenweg des Menschen" is a different, and quite peculiar, one from the Hardy/Morgan one (below) most people understand to be the "aquatic ape theory". It is not even clear if his ideas are Darwinist, and he certainly doubts that humans evolved from apes. It lacks a cohesive timescale and really just proposes certain anatomical traits, such as our feet, have analogues with aquatic mammals.

Hardy/Morgan (1960... 2007) "Aquatic Ape Hypothesis" (AAH) is probably the one most people think about when they hear about the idea. Hardy was the first to publish his thoughts in an English-language journal and Morgan has been the most vociferous and long-running proponent of the idea, writing six books on the subject. Basically it proposes a distinct "more aquatic" phase at around the time of the ape-human split which was largely coastal (but Morgan has since accepted that it may have also comrpised fresh water elements too.) Hardy was quite happy that this 'phase' ended and man returned to a fully terrestrial life afterwards.

Verhaegen et al (2002) "Aquarboreal Apes-Amphibious Ancestors Model." Quite different again, and more complex, is the idea that the ancestors of all great apes were already somewhat waterside dwelling. Unlike Hardy/Morgan, who think of the LCA as more chimp/gorilla like, proponents of this view see the LCA as wading-climbing (hence aquarboreal) apes that were already somewhat bipedal, living in swamps and coastal mangrove forests. They make the distinction between this kind of 'default' bipedalism and our own and suggest that human ancestors, after the split with the apes, went through a "more aquatic" or amphibious stage which explains the genus Homo. They see Homo erectus as the most aquatic phase in human evolution and suggest that traits such as their heavy bones are best explained as diving adaptations. They regard diving as key in the evolution of human bipedalism as it would select for traits making the hominid more streamlined. This "linear build", they say, is a necessary prerequisite for modern human bipedalism.

Ellis' "Wetland Ape" hypothesis. Ellis (e g. 1993) simply proposed, in a series of papers in the late 80s/and 90s, that wetland habitats would have been ideally suited, ecologically, for early hominids. There is a lot of overlap here with the early phase of the previous model (the 'aquarboreal phase') but Ellis does not delve into any later speculation about modern human evolution. Had recent support from Richard Wrangham in 2005.

Crawford, Cunnane, Broadhurst et al "Marine Food Chain based Encephalisation" hypothesis. In a set of detailed papers and books, these brain chemists/nutritionists proposed that the process of human encephalisation could not have occurred without a significant shift in diet. Specifically, an increase in essential fatty acids and micronutrients which are best found in the marine food chain. We are all aware today of the known health benefits of omega 3 fatty acids and of Iodine in salt, both rich in fish and shelffish. These authors do not lay out a detailed timescale for this switch in diet and some (e.g. Crawford) claim that it must have been very early, even contradicting the molecular clock estimates for ape-human divergence.

Carsten Niemitz' (2002) "Amphibisce Generalistheorie" is another, quite different waterside hypothesis of human origins. He goes out of his way to distance himself from what he calls "the aquatic ape theory" and is quite damning in his criticism of it, but then goes on to promote the view that bipedal wading is the perfect pre-requisite for human bipedality. Controversially, a part of Niemitz's model is that "we didn't come doewn from the trees". Like many of these ideas, I think he has some very good point as well as some bad ones.

My own "River Apes... Coastal People" Model. Struck by the impression that all of the models above seem to have some aspects absolutely correct but others frustratingly wrong, I decided to form a kind of 'hybrid' model, choosing the most plausible, evidence-based parts of each and adding a few bits of my own. Basically the model agrees with the Verhaegen et al/Ellis 'aquarboreal ape' phase for the LCA and before but proposes that the actual ape-human divergence was caused by some of these wading-climbing apes finding themselves east of the rift where a shift to aridity caused their forest habitats to shrink ever closer to seasonally flooded gallery forests (the "river apes" part.) The idea is that simply adding a component to their lives where their habitat is flooded for several months a year was enough to to consolidate their bipedality, wheras the apes west of the rift, living in tropical rain forests were not compelled to do so and increasingly adopted knuckle-walking. The model suggests that as rivers lead to the sea, human ancestors (already fully bipedal) would have eventually arrived at the coasts where other changes (such as encephalasation/dental reduction, body hair loss and increased infant/female adipocity etc) would have been selected for (the "coastal people" part). It assumes that H erectus was more aquatic than their ancestors (hence its diaspora as far as Indonesia) but that early modern Homo sapiens was the most aquatic of them all. The key point, I suppose, about this model is that it stresses a simple fact from population genetics that even very slight selection can and does make a profound difference in populations in a very short amount of time. Seen in this light, when I said early modern Homo sapiens was the most aquatic of them all, I do not mean that they were 'aquatic' at all in the traditional sense, just that they lived at coasts more and were therefore exposed to the risk of drowning more than at any time in their past. Their success as a species soon forced them to move to, and eventually exploit, every other niche on the planet but, according to this model, our ancestral niche was the coast.

There are other ideas too, some more extreme such as Hagstrom's "Passionate Ape" which I believe actually proposes that human ancestors at one time lived in the sea pretty much full time, and others much more mild, such as Philip Tobias' "Water and Human Evolution" idea which simply urges his peers to think more about the role living by water played in our evolution. I won't go into them here. Suffice to say that calling "the" idea the "aquatic ape theory" is at best insufficient and at worst very misleading.

I hope members will be interested enough in these ideas to debate them openly and objectively.

All the best

I am posting this before I have read the OP. Hope that doesn't screw things up.

Algis, This is my reply to one of your former posts in the other thread:

In my defence I have had years of debating this on other newsgroups (such as sci.anthro.paleo) where there is a great deal of hostility to the idea and its proponents. I also have been trying to get a paper published on the wading hypothesis now for three years and the responses from the editors and reviewers (on the one ocassion it did get to peer review) were very disappointing to say the least. I'm sorry you don't find the wading model for bipedal origins satisfying. To me it answers this question, which has confused the field for 150 years, perfectly.

I wasn't aware there was any hostility on the hypothesis, only some of its points and the extent of influence. Or perhaps I only perceive that because I am not hostile to it, I'm just questioning of it. :Dunno:

Show nested quote + Any significant diet change will effect the structure of teeth and the jaw. I do not immediately equate this with aquatic food sources. Well put it this way, to explain encephalisation we need a change to an energy-rich diet. What energy rich-diet is there on the savannh? Meat. So humans would have to be the first species that ever underwent increased carnivoroy at exactly the same time that they underwent dental reduction. It soundds like special pleading to me. Much simpler to postulate the marine food chain. One tap of a pebble and you have a soft, nutritious meal. High energy, no need for big teeth.

Not only does that sentence require a qualifier (I have not researched thoroughly, but I am very highly skeptical of that claim), change in dental structure is exactly what would be expected with a significant change in diet. Why would there be a delay in the development? Or do you not mean to imply this?

I am certainly not a dental expert (perhaps someone can correct me if I am wrong), but the human jaw does not clearly indicate much more than an omnivorous diet. Aside from increased tooth decay coinciding with the invention of highly processed grain, I do not know of any strong dental indicators of a specific food source being exploited in our history.

Show nested quote + I do not support the loss of hair with gain of fat, purely for thermoregulation, and I have not heard anyone propose this. Every suggested pathway I have heard uses other selective pressures, everything from vitamin D to parasites. No one suggests such a ludicrous notion of replacing one method for another without reason. Langdon (1997) uses that precise argument, and it is fairly common. But this is my point. The "orthodox" arguments are all over the place. They're often contradictory. Waterside hypotheses, by contrast, are consistant and complimentary. [Langdon, J. Umbrella hypotheses and parsimony in human evolution: a critique of the Aquatic Ape Hypothesis. Journal of Human Evolution 33:479-494, (1997).]

To be fair, the additional pressure that Langdon postulates is long periods of extreme endurance, like hunting, requiring a better system for removing large amounts of excess heat.

The lifestyle Langdon postulates as the motivator for the development of of our current system makes sense to me if you switch around some of the causes and effects. I think it is more likely that the development of sweat glands came before the loss of most body hair for thermoregulation during periods of extreme activity. As this developed, body hair would become more and more a liability. Not only does it inhibit the evaporation of sweat when needed, wet hair becomes a problem when temperatures cool. But I don't regard this as a solve-all either.

Show nested quote + This is not different, no better, than other explanations. If moving through water was regular enough to have a survival rate differential (based on being bipedal), what is wrong with regularly carrying tools, food, etc. enough to have a survival rate differential? Obviously, an individual that can walk longer distances with "gear" has a survival advantage, this explanation is just as efficient as the one you have offered. And, again, I do not equate wading with walking on land. I do not see this as enough of a pressure to evolve bipedalism. Perhaps in tandem with other pressures, but not on its own. And do not forget that apes DO walk in a bipedal fashion occasionally (if still very rarely), no water needed. With a pressure to make this advantageous bipedalism can evolve without regular wading. [...] The problem is it must have been less energy efficieent to move bipedally for an early (and hence not anatomically adapted) biped. This inefficiency must have been exacerbated by carrying, not aided by it. Wading solves that problem at a stroke because even apes without anatomical adaptations for bipedalism move bipedally in shallow water. [...]

But I see this as part of the problem, just because they are required to move bipedally in water does not mean they are pressured to do so on land. Like others, I question how much of a pressure wading actually provided, because, as I see it, for it to be the main contributing factor for bipedalism, enough time would have to be spent in water (compared to land) and account for enough structural changes that it became structurally difficult to have a quadrupedal mode on land. I think that requires QUITE an aquatic lifestyle. And I am not sure there is enough evidence for an aquatic lifestyle to that degree.

Show nested quote + Not if drag in unimportant to the activities of the creature and the structural cause of the drag IS important to it. Well getting food is quite important, I'd say. If you're in a group swimming back from an off shore island against the tide, having less drag is likely to make all the difference between life and death.

True. This would have to have been a regular occurrence to off-set the benefit of the insulation. Was the area of fossil finds this aquatic?

On a side note: Are there many anatomical parallels with proboscis monkeys? As I understand it, they live in a fairly watery environment requiring the regular crossing of shallow channels.

Show nested quote + This, of course, applies to all explanations equally Yes, it does. But the point about moving through water, as opposed to moving on land, is that even if you only spend 1% of your time in water, you might still drown there. So it will have a disproportionately important effect on selection.

The number game still applies to all explanations equally. The point of a survival differential is taken. I don't dispute the plausibility of an effect, just saying that other explanations that can show a survival differential (or variable fitness) are on equal footing in that regard.

There is no doubt that the response to the so-called "aquatic ape theory" by the field of paleoanthropology for 50 years has been, shall we say, disappointing. I'm not claiming there's a conspiracy, just ignorance. It was misunderstood, by Le Gros Clark, on day one and since then two generations of students have either been taught a distorted version of the idea or nothing about it at all. My statement "The bias and dogma against this idea is apparently so strong it even trumps Darwinism - how bizarre is that?" is the result of years of debating this with people who hold the 'orthodox' view. For example, I made that point (the fact we swim better than apes suggests natural selection has made us that way) at UCL to Dr Mark Collard and he would not have it. Instead he came out with arguments like "we ride bikes", "play musical instruments" ... anything but admit that it was actually quite likely and parsimonious to just assume that, like all the other permutations, it was due to natural selection.

If others argue it simply from bias and ignorance, I sympathize. That is unfortunate. I think perhaps it is merely stubbornness. This is not necessarily a bad thing as it forces proponents of a new idea to form more solid arguments and evidence. It also requires some amount of a successful falsification of the previous theory. We want to get our hypotheses more accurate and more supported, not more numerous and speculative. Again, good luck in your efforts.

I think I understand the point Dr. Collard was making, it requires more to argue natural selection for what can be learned behaviors. For us, our brain and capacity to learn trumps many pressures for an instinctive or anatomical solution to a problem. Our ability to ride a bike does not develop from a selective pressure to be able to ride bikes. It is learned. A better approach may be to focus on what is provably instinctive with regards to swimming. :Dunno:

Show nested quote + You missed the point and use a poor example. The comparison does not equate, either. Give that ape the option of leaving the water and it will in short order. Give that ape an object that requires transporting for the reward of food, and it will go further. Apply this pressure constantly, and you get an increase in bipedal capability. Neither proposal excludes or reduces the probability of the other. Sorry but I think you missed the point. A quadrupedal ape in waist deep water would die. A quadrupedal (or tripodal) ape could still carry its food without getting upright. I agree they're not mutually exclusive. Wading only encourages bipedalism, and that is true whetheer it's carryingg bipedalism, postural feedign bipedalism, threat display bipedalism or any other kind. I was implying bipedal transporting, like a large stone (often used by chimps as anvils for the obvious benefit of getting to food). In an instance where the food can not be transported, but such a tool must be in order to exploit the resource, an ability to transport the tool farther and more efficiently would be selected for. Because, otherwise, the resource remains untapped (or tapped by others). Hypothetical large kills would cause there to be benefit for this ability as well. So would multiple tools, should they be required to exploit a resource. I didn't miss the point. I was showing that the wading model is no more solid than others to provide a pressure for bipedalism.   [quote] Fat is just as associated with diet. Another ape's dietary needs may not require such storage for pregnancy and infancy. Diet change is just as likely to alter adipocity as aquatic development. But infants put on weight in the last trimester irrespective of the diet of their mother, to the detriment of the mother's health. Eric, you didn't answer my point: If human infants developed fat because of dietary requirements, why only us? Are other primates not also always on the verge of starvation? If a species evolves in a diet-harsh environment what possible sense is there in pumping high energy fat into a baby that might be lost any day to a predator? Why would only humans, out of all the savannah ecosystem, adopt this strategy? It's just special pleading. The most parsimonious explanation, as usual, is the coastal niche one.

Diet is not just food quantity and energy needs, it is also nutritional needs, food sources and their availability, seasonal factors, etc. There is a LOT to consider when talking about diet. Just a nutritional source easily available to another ape and unexploited by an early hominids diet could form a difference in behavior and/or physiology. If our diet OR dietary needs were sufficiently different than other apes, it is certainly possible for that to effect our adipocity. I would say that a more carnivorous diet would fit that description, easily.

Nutrition is another area out of my expertise. I don't know just what and how many vitamins and other nutrients are stored in fat, or which ones might be important to infant health and development, but a scenario where the source of such a nutrient is unreliable there would definitely be a pressure for behavioral, or physiological, storage of it for use during pregnancy. I know this sounds like speculation. Only take from it that diet is a strong influence on many aspects of anatomy and physiology.

Later. And thanks for the reading recommendations.

Hi Genjix and Steal,

The areas with a proximity to water - be it a lake or a river will have been favourite niches for pioneering savannah apes.

Knowing the geography of East Africa - I don't recall any areas of seasonally flooded galleries.

These animals will have no doubt feasted on the easy prey (the animals I listed) at these water edges. They will have also eaten termites - as termites mounds are extremely numerous in Africa (chimpanzees are quite partial to termites - according to Jane Goodall) and acacia seed pods, and honey etc. So they were probably omnivorous to the extreme. All of these things are easy to chew and so their teeth will have been, more than likely, similar to rainforest apes, fairly even.

I think it was a long time before their brain power increased and it was likely that this started to come about when they began throwing their digging sticks or stones at gazelle herds drinking at the waters edges. The ability to improve their 'spears' and clubs and their throwing techniques - would be selective forces for greater intelligence (as the more intelligent ones would have better techniques and hence better kill rates and hence better survivability). New techniques which were successful would be passed onto other members of the group and future generations. This would be the beginnings of a 'general knowledge'.Those apes with the greater ability to store greater bytes of knowledge would survive over others. Knowledge is power and can trump intelligence sometimes. The braincase would vault upwards incrementally over generations - to accomodate more megabytes of memory.

Once these hunting techniques were really refined and effective, these apes would be free to leave the water resources and follow the game - some of which were probably migrating long distances. They would switch to a diet almost exclusively of meat - and blood would replace drinking water. The meat would be raw and tough and so initially the offal would be most easily dealt with.

What I am trying to say - is that these apes will have had a pioneering stage near water - but that would not have meant that they were aquatic apes - merchimps - losing their hair for the streamlining effect etc.
Also adipose tissue is more associated with thermoregulation than streamlining- mountain gorillas have it, apparently. We have it because we live in cold climates. Savannah apes may not have needed so much of it. The level of adipose tissue varies considerably amongst humans.

Good point. One of the biggest criticism many in the field have with proponents of these ideas is that they don't do "proper science". They just speculate. The problem is Hardy retired before announcing his idea, thus surrendering any chance of co-opting a band of loyal PhD students who might work under his guidance. Morgan isn't even a scientist, she'd a popular writer, so she didn't have the chance to do any of the experiments anyway. So, basically, at least one generation has been lost where a lot of good science might have been done. It's not quite true anyway, of course, because some of the ideas, such as the encehalisation from marine food chain, is properly installed withing the literature as a resectable theory.

I think it is also fair, however, to ask another question. Instead of "why are some aquatic ape proponents such bad scientists?" why not ask "why have no good scientists even looked at this thing?"

I think it is changing now in any case. There are a few of us engaged in "proper" research in a few universities around the world. But, you know, it's dificult to change a paradigm. To do that you have to get published in a good peer reviewed journal. That's very difficult at the best of times but much harder when you're challanging the very paradigm the editors and reviewers have probably built their reputations on.

I know I am guilty of speculating - but it is only through speculating that robust theory emerges. Then you can test different parts of the theory or research information that backs up your theory. This is where the internet comes in; it can provide answers to your questions in seconds. No more going down to the library! Every theory starts with speculation. Darwin speculated.

That is the beauty of web-sites like these - you are free to have your say. You don't have to be an eminent scientist or guilded writer - you can make your own comments in an informal way (and without peer-review status) - ideas which may be the culmination of many years of enquiry. You can lay out a skeleton of a theory and then add flesh to it bit by bit - using information gained by other scientist's research. You ask yourself the question. "It is likely this happened - and if this happened something else linked to this might have happened". Its a bit like doing a large jigsaw puzzle without the picture on the lid. Each piece has to mesh properly with three or four other pieces. Speculation also features a lot in solving jig saw puzzles.

Many teachers of evolution, including some of those in universities don't get much further than passing on their own knowledge. I call them 'parrots' because they are just repeating stuff. But because they are at the top of their profession, and widely respected they do not want their interpretations displaced by newcomers and new ideas. It makes them look a bit dumb because they should have thought of it.

Take for example, it has only been recently accepted that all human races are derived from humans which came out of Africa.

It used to be the Out of Africa Theory versus the Multi Origin Theory. Mitochondrial RNA has confirmed the Out of Africa Theory - but surely it was obvious that we would not be able to easily interbreed as we do - if some races had different origins to others?

I did an applied Zoology Hons degree at Newcastle upon Tyne University and intended to do a PhD but got involved in a family business. I have always maintained a deep interest in evolution and drew inspiration from Richard Leakey's TV programmes in the 1980's about the Evolution of Mankind. I have been researching evolution on the internet for the past twelve years or so. This does not make me an eminent biologist, but I intend to get this evolution message across to as many people as I can. Any scientist is perfectly free to scrutinize my work and correct me if I am going wrong.
I draw inspiration from Richard Dawkins - and wish him well in this battle against superstition. There are not enough people like him - willing to 'rock the boat'. Carl Sagan was another genius.

holy fucking shit

I dont think you necessarily find lots of sharp tools just lying around the savannah. The point is that humans somehow learned to make these sharp tools for themselves by cracking stones and then chipping away at them. Where better to begin to learn how to do that, than on pebbly beaches where there are millions of them? They may be rounded by erosion to start with, but once they've been cracked against a shellfish, or another pebble they may break open and create sharp edges.

I'm not pretending that humans didn't use stone tools later to butcher meat and to skin mammals, and that they did so miles from the sea. I'm just agreeing with Alister Hardy, Elaine Morgan and Carl Sauer who have argued that this was the perfect place for the culture to have begun.