Evolved from what?

Funny, yes, but not completely stupid. About 20 years ago there was a Scientific American article on the genome with a line something like: One of the first things to evolve was the ability to evolve.

The point was that the cellular (or pre-cellular) infrastructure that shepherds the reproduction of DNA has to keep the mutation rate low enough that most offspring are still viable, but still sloppy enough to let some mutations occur. If the mechanism is too robust, the species would never be able to adapt or diverge and would almost surely be gone by now.

It’s not just you (anymore).

I think I see runner pat’s point. axolotyl appears to be one more in a long line that have come here and asked this same rhetorical question thinking that they are striking a blow against evolution.

They’re not here sincerely looking for an answer. Rather, they think they’re cleverly blowing away the whole “lie” of evolution. The fact that the question has an answer (or rather that the question makes incorrect assumptions) is not likely to sway them.

If you know for sure that a 15-million year old species has descendants around today, then when it went “extinct” is just a matter of semantics. This is how I’d define it: If you went back in a time machine and brought an organism forward in time, at what point would it no longer be able to breed with its descendants? Even if the descendants looked remarkably similar to their ancestor, I would guess that they would be, by this definition, different species after a few million years.

By the way, I would hazard to guess that any 15-million year old fossil we’ve dug up is from a species that has left no descendants - and is thus extinct by any definition. The vast majority of species leave no descendants over timescales of tens-of-millions of year; the species around today diverged from the tiny minority of exceptions. Your chance of finding a fossil from one of those lucky species is very small.

Given your username, I thought more of Christ on a Hot Tin Roof.

The Anglican church and the Lutheran church arose from the Catholic church. And yet there are still Catholics! Ergo: God does not exist.

Well, not any MORE, it isn’t. :smiley:

I’ll save you a seat on the bus to Hell, if you want. But I get the window.

Three.

The points everyone has to realize about evolution:

  • genetics, and so the characteristics of any living thing, can change randomly in response to random mutations. These happen by chance, cosmic or background radiation, chemicals or other environmental issues, etc.

-Most of these changes have no effect or are bad for the organism. It may not survive. Some changes are not passed on, as the change does not affect the genetic material that is passed on to offspring.

-if the mutation is beneficial, if it improves the odds the organism will survive, thrive, and improves the odds of the descendant organisms also surviving, then likely it will stick around; if it is really helpful, it may become a dominant trait. For example, colour vision. We have 3 sets of cones in our eyes that see 3 different wavelengths, making up colours. A predator that has 1 set sees black and white. A simple mutation where the gene is duplicated, but the second one is more sensitive for a different wavelength, may help a predator pick out food that is the same shade as the background but different hue. That becomes a useful charateristic; that animal and its offspring eat bette, live longer, find the food first.

-Organisms tend to evolve when there is an opportunity to exploit. If there is a food source, or a better way to hide, etc. - the animal best suited to take advantage of that survives, outcompetes the others.

-Humans are decendants of the tree-dwellers like monkeys, come down to wander the savannah and chase down prey. We evolved a very efficient mechansim - two feet good, four feet badder - that let use outrun wildbeests and make them food. We can’t beat them on speed, but we can keep up with and harrass quadrupeds until they fall over from exhaustion. Very few animals can run a marathon, day after day, like a human. As a consequence, we learned to eat meat - protein and fat - very efficient sources of food energy.

Why are there still monkeys? Because we suck at getting fruit from high branches. Why are there apes? Because we prefer the open plains to the denser forest areas, we don’t climb easily. Animals with very strong arms that can also climb trees are more efficient and survive better in that environment.

What there are not any more, is australopithecus and similar human types from 3 to 5 million years ago. Maybe they also chased down food and figured out how to use sticks to chase hyenas away from carcasses; but a bigger better version of themselves probably replaced them over the millenia.

It’s all about opportnities and ecological niches. Every advantage is also a disadvantage -trade-offs. A big brain helps us in many situations, but requires more food to keep working. Big muscles mean someone is much stronger, but starves faster when food is scarce. A predator may find colour vision an advantage, but if the main method of hunting is by sense of smell (dogs, cats) then it’s not a great advantage. A horse cannot normally survive with a broken leg, while a cat or wolf might, because the latter might eat by limping from abandoned carcass to carcass until the bone knits; while a horse that can’t run away from the wolves is basically Mother Nature’s drive-in diner…

Of course, if someone persists in believing the world is flat or evolution is not happening or the sun revolves around the earth… all the logic in the world will not work.

Probably not. We can’t know for sure, but it is likely we were scavengers long before we were hunters. Upright posture precedes tone tool making by millions of years.

It’s unlikely that Australopithecinces were hunters.

But basically the reason we’re here and monkeys are here, is because monkeys are very good at doing things we can’t to feed and protect themselves. Try catching one, whether you’re a human or a big cat. The reason we’re here and australopithecas, errectus, etc. are not is because we did the same as them, only better faster etc. If at first we were only slightly better, that was enough. We win. There was no special environment (like, perhaps, dense jungle…) where they could maybe outcompete us and survive.

Which explains why he hasn’t been back to defend to defend his “argument.”

Not really. There were probably lots of species of Australopithicines (or non-Homo hominins) that we didn’t compete with. As for Erectus, it does appear that we absorbed them into our line, to some extent, the same way we did with Neanderthals. It is likely that we outcompeted the bulk of the Neanderthals.

At any rate, the reason there are still monkeys is that on a small population of monkeys evolved in apes, and only a small population of apes that evolved into us. But the monkey alive today aren’t the same as the ones that were around millions of year ago when all this splitting was happening.

Another point everyone should know about evolution is that organisms don’t evolve; populations of organisms do :wink:

Why? I mean, both us and chimps supplement our diet with meat, it stands to reason our common ancestor did as well. Or did hominids abandon that for a while only to pick it up again later? There have also been multiple reports dating back over a decade of primitive tools being found with/near Australopithecus, or in the same time frame. The genus homo is not the only toolmaker. What were those tools for (if they were tools), if not for hunting?

davidm writes:

> I think I see runner pat’s point. axolotyl appears to be one more in a long line
> that have come here and asked this same rhetorical question thinking that they
> are striking a blow against evolution.
>
> They’re not here sincerely looking for an answer. Rather, they think they’re
> cleverly blowing away the whole “lie” of evolution. The fact that the question
> has an answer (or rather that the question makes incorrect assumptions) is not
> likely to sway them.

Yes, and my point is that we should never be flustered by their questions. Calmly and clearly answer their questions regardless of whether they really want to know the answer at all. If we reply by telling them that they are jerks or idiots, they get the reaction from us that they expect. They want us to veer off from any intelligent discussion of their point into reacting emotionally to them. This confirms them in their belief that we don’t have any reasoned answer to their questions, but we just want them to disappear because we think they’re worthless. By answering their questions with reasoned, intelligent answers, we show them that we can always be non-emotional about the issue. Then they’re the ones acting like jerks, while we’re the ones that stick to honest argumentation.

It’s unlikely that Australopethecines did much more than supplement their diet with meet. I should have said that they probably weren’t hunters like we are. Scavengers, more likely, if at all. It’s thought that they lived both an arboreal and terrestrial lifestyle, btw. I’m not aware of stone tools associated with Australopithecus sites. Do you have a cite for that? Homo and Australopithecus overlapped in timeframe.

http://www.nature.com/nature/journal/v466/n7308/abs/nature09248.html
http://www.nature.com/nature/journal/v466/n7308/abs/466828a.html

We, as a species, until recently, didn’t eat a great amount of meat either. I’m not talking scavenger either, I’m talking hunting in groups to chase down, kill, and consume animals like small squirrels or monkeys or such. Modern chimps use spears, and teach their young how to make and use such. If Lucy had been doing so, how likely is it we’d ever find such a spear? Sure, the evidence is preliminary and non-conclusive, but the trend in hominid research ever since it came to be is to push the dates back farther and farther than previously thought, and while this leads to some outlandish claims, I don’t see this as being terribly unreasonable. As evidenced by modern chimps and Homo floresiensis/neanderthalensis, the structure of the brain matters more than size, and Lucy has had those hands a lot freer a lot longer than modern chimps.