bombus

I've seen a film of that - african's hunting a elan I think. However, what struck me was that it was only possible because the humans could carry their water with them. Does this suggest that we started carrying water with us before we lost our hair? Else, surely we'd have suffered from dehydration. Sweating in hot dery places aint a good idea unless water is readily available. This is why I tend towards the AAH prior to us living on the savannah. i.e., we'd already lost our hair.

Lets face it, humans are pretty lousy at everything until trained and experienced, but the ability of human babies is NOT that easily explained. Nor would the ability to survive from drowning for a short period be something a terrestrial mammal would evolve. IMHO it points to humans giving birth in water - probably as a protection from predators. It gives the mother enough time to gather it in its arms. Drop a new born puppy, or even chimp into water and see what happens! . They can't hold their breath as well though! Oddly much of the ability to hold breath underwater is actually psychological. Free divers can overcome the natural desire to breath and stay submerged for much longer than most of us could. The point is that humans have a physiological ability to do this far in excess of what we should be expected to have.

Human babies can swim as soon as they are born. They automatically hold their breath, rise to the surface and do not breath until their face is out of the water. They retain this ability until around 3 months old. Humans are actually far better swimmers than they deserve to be, and our ability to hold our breath underwater far surpasses any terrestrial mammal. In fact it is almost on par with seals. We would not have been fully aquatic at any time, it's a bit of a misnomer, but semi-aquatic. maybe living on and foraging in coastal areas. I doubt fossils would be found in the way you suggest. they would probably be found in what were coastal areas (and possibly are?). As the answer above, I doubt we'd have been sea hunters, but maybe we lived off seafood (shellfish etc). In fact, a seafood diet is the healthiest for humans as its full of omega 3 and oils that keep our arteries clear. CD Dawin, I have seen that anti AH website before. It is full of strawman arguments, and inaccuracies. Your point about most aquatic mammals being 'haired' is interesting, but not actually that important. Most aquatic mammals have short or no legs but frogs have long legs - it all depends on what the starting point is and what evolutionary processes then come into play. Maybe we were living in muddy waters or boggy areas where hair was a disadvantage. Also cetaceans have no hair, as do hippos, elephants, rhino's, all of which are either semi aquatic or have had semi aquatic ancestors.

This entire argument is built on conjecture. Gorillas put huge weight onto their front limbs when walking, and so do chimps. Well, it could be that it was an evolutionary advantage for swimming and so became an attractive feature that went into 'overdrive' in the males - like the peacocks tail. However, it's not a particularly important factor in the argument. Ever seen a sealion hold a ball on it's nose? Meercats couldn't do that. I'd bet otters have much better balance than meerkats too. Well I'd say they are pretty flipper shaped compared to other primates. Your note about the feet of australopithecines is interesting. It's possible that it was about this time that they homonids became semi-aquatic. It's simply not true that there is piteous support. There is loads. Even Sir David Attenborough is a recent convert to the theory.

Absolutely right! Not only that, but the 'defense' industries have made £billions out of Iraq. That's why they are happy to have a war with Iran - or anybody else for that matter. The poor soldiers pay with their lives to keep the bosses rich - as ever...

Outdated, falsified hypotheses? That well describes the savannah theory. A Victorian theory, way out of date and contrary to the evidence. I am right I tell ya. Just you wait and see!!!

There is hardly any difference between them.. I feel you are clutching at straws! The females still have longer noses than most monkeys. The human nose flap I refer to is, well, the human nose. C/f other primates noses! I may be clutching at straws here... Penguins don't walk quadrupally on land. The others have no choice, but the balance and ability to stand kinda upright shown by sealions, and otters for that matter, are abilities that an aquatic or semi-aquatic lifestyle can bring. Homonids had long legs to start with though, so these would have been used in a fashion similar to frogs, which are also swimmers with long legs. So, our body form would become elongated and 'straight' effectively pre-adapting us for walking upright. Also look at our feet - they are flipper shaped. Fossil evidence is already there - it just depends on the interpretation. It's amazing how hostile people are to the aquatic theory despite it answering ALL the questions about human evolution (hair loss, sub cutaneous fat, babies swimming as soon as they are born, tears, dive reflex etc etc etc) - unlike the savannah theory. It is the truth, and I will one day be proven right, and everyone will pretend they agreed with me all the while...

I know humans didn't evolve from baboons, but they did evolve from the common ancestor of humans and chimps. I'd bet they were very chimp-like and walked on four limbs most of the time. Why would they walk on two legs when they moved out to the savannah if four legs is better and evolution could have taken them either way? Proboscis monkeys are thye best swimmers, and regularly walk upright. They have also developed a nose flap that prevents water going straight up the nostrils - like humans maybe? I know that only penguins actually walk upright, but the others all have a body aligned in a similar way, it's just that they don't walk upright as they can't! Maybe you miss the point? Penguins btw are the only truly upright animal apart from humans. Other birds are not truly upright. Meerkats stand upright to look out for predators, but still run on all fours. It's swimming that did it. One day I'll be proven right...

Swimming. Without a doubt IMHO. Savanahh living primates are more likely to run on all fours compared to forest dwellers (c/f baboons v orangutans) C/f penguins, seals, sea lions, otters, cetaceans, all have a fully 'upright' stance (seals, cetaceans etc lie flat, but the body design is similar)

thanks for your answers everyone

If cosmic rays are so powerful (and I'm sure they are), why do we need to build the LHC at all? Can we not just study particles that get hit by cosmic rays? They are so numerous afterall. Is the fact that the LHC slams particles together head-on at near light speed the difference? If so, does that not make the cosmic ray comparison a little shaky? Please someone explain in very simple terms.

The criteria for species and sub-species are not particularly strict and are open to interpretation. It tends to boil down to convenience if the truth be told. Some class Felis domesticus/catus as a sub-species of F. sylvestris, others don't. Also, it would seem some divide F. catus into subspecies: * F. catus anura - the Manx * F. catus siamensis - the Siamese * F. catus cartusenensis - the Chartreux * F. catus angorensis - the Turkish Angora

could this not have waited until we could do it in space though, just to be on the safe side?

Well, that's not quite true. Species that can interbreed but don't (e.g via geographical isolation, or behaviour) tend to diverge intospecies tat cannot interbreed. The latter is usually a forerunner to the former.

This depends on your definition of an insect. Silverfish for example are classed as Class Insecta in many texts. I think the term Hexapod/Hexapoda is now used instead of Insect/Insecta to include all six legged arthropods including both Apteregotes (all wingless insects) and Pteregotes (winged and secondarily wingless insects). Interesting stuff. I like cladistics!

Some bacteria have stayed bacteria, others have become extinct, and some of those have evolved into more complex forms of life. Currently exisiting species of bacteria do very well as they are, have little need to 'evolve' and will undoubtedly outlive humans and possibly everything else too. Being complex does not make one any better. Evolution only cares about which genes get passed on, so if the best way to get ones genes passed on is to stay as one is then there is no selective pressure to change - and quite the opposite in many cases.

Some may be interested in the excerpt below from a paper by Nick Bostrom: There have been speculations that future high-energy particle accelerator experiments may cause a breakdown of a metastable vacuum state that our part of the cosmos might be in, converting it into a “true” vacuum of lower energy density [45]. This would result in an expanding bubble of total destruction that would sweep through the galaxy and beyond at the speed of light, tearing all matter apart as it proceeds. Another conceivability is that accelerator experiments might produce negatively charged stable “strangelets” (a hypothetical form of nuclear matter) or create a mini black hole that would sink to the center of the Earth and start accreting the rest of the planet [46]. These outcomes seem to be impossible given our best current physical theories. But the reason we do the experiments is precisely that we don’t really know what will happen. A more reassuring argument is that the energy densities attained in present day accelerators are far lower than those that occur naturally in collisions between cosmic rays [46,47]. It’s possible, however, that factors other than energy density are relevant for these hypothetical processes, and that those factors will be brought together in novel ways in future experiments. The main reason for concern in the “physics disasters” category is the meta-level observation that discoveries of all sorts of weird physical phenomena are made all the time, so even if right now all the particular physics disasters we have conceived of were absurdly improbable or impossible, there could be other more realistic failure-modes waiting to be uncovered.

It's not semantics, it's just that sexual selection IS one facet of natural selection. Others are competion (intra and inter species), environmental factors, behaviour, the list goes on. There is no need to separate out sexual selection, and it's often not easy to that anyway. Natural selection doesn't care about the reason - only if the individuals genes are successfully passed on.

I would tend to disagree with that most strongly. Sexual selection is definitiely natural selection. It's not man-made selection so it is natural selection! Natural selection does not just include competiton for scarce resources. Sexual selection produced the peacocks tail, and the plumage of many birds, and badgers stripes, and probably human's big brains.

Top down control can survive if those at the top own the means of production in a manner seen as being fair (even if it is not) and more importantly, if they control information!

There is no single definition of a species. It's a pretty fuzzy concept really. Could the hybrid frog reproduce or was it sterile?

What is the exact date and time (in GMT or BST) that the LHC is to be run for the first time?

Sexual selection is a form of natural selection.

Measures to prevent global warming could lead to increased prosperity due to employment in new sustainable technologies. Think (for example) how many people could be employed in the windfarm/solar/tidal/geothermal/biomass/nuclear industries, and how much shares in those technologies would be worth, and how much business that leads to, etc etc etc.

If the LHC at CERN does create mini black hole(s) and in the race between hawking radiation and matter munching the latter wins... How long would it take for the Earth to be destroyed?