Well I'll Be A Monkey's Uncle

killproc writes "A new report suggests that interbreeding between humans and chimpanzees happened a lot more recently than was previously thought. The report, published in the most recent issue of the journal Nature, estimates that final break between the human and chimpanzee species did not come until 6.3 million years ago at the earliest, and probably less than 5.4 million years ago."

Chimps ARE NOT MONKEYS

[Hamster Lover]

I know the headline was probably meant as a joke, but before the Creationists go, um, ape on us it should be noted that Chimpanzees, Gorillas, Bonobos, Orangutangs and Man are all "great apes", evolved from earlier species. Apes evolved from Old World Monkeys about 25 million years ago.

Apes are differentiated from monkeys by their larger brain size, versatile shoulder joints, and lack a tail.

Re:Misleading

[homer_ca]

Yes, the headlines saying "humans" are just dumb. They're probably talking about species like Australopithecus [wikipedia.org] which are far from being humans. They evolved a pelvis that enabled them to walk upright, but their brains were 35% the size of a human brain.

Hold it a second!

[anzha]

John Hawks [johnhawks.net], a professor of anthropology, has a pretty sound and harsh refutation [johnhawks.net] of the article. It looks like, if John is to be followed, that this is some pretty wishful thinking and sloppy work.

He has a follow-up [johnhawks.net] post on his weblog as well.

Maybe it was the shepards?

[shotgunefx]

Hell, some people [thesmokinggun.com] are still screwing animals so I wouldn't be that suprised.

Re:Key line from TFA

[Daniel Dvorkin]

Three problems with that definition:

1. It doesn't always hold. Animal species are usually defined as breeding populations; two populations which wouldn't normally interbreed may still be interfertile.

2. Borderline cases exist. The offspring of a horse and a donkey is almost always sterile, but I believe there have in fact been (very rare) fertile mules; on the other extreme, ligers and tigons are usually fertile, but frequently not.

3. It's not relevant at all to organisms which reproduce asexually.

There is no magic moment when one species becomes two. We made the terminology up; nature (or God, if you prefer) didn't.

Re:Key line from TFA

[LockeOak]

The biological species concept (that species are empirically defined as whether or not they interbreed and produce fertile offspring) is convenient but does not always reflect actual gene flow. First of all, it completely falls apart when applied to asexually reproducing organisms, such as bacteria, some fungi and even a few reptiles and insects. Then there's the difference between "can" and "do"; there are many organisms that are considered different species that can, under artificial conditions such as captivity or through artificial insemination, be made to produce fertile hybrids. This doesn't happen in nature, however, because of behavioral or temporal/spatial barriers to their breeding. Perhaps one species only breeds in late May, while another that otherwise would produce fertile hybrids only enters estrus in early March. The two will never (or extremely rarely) interbreed and the two populations will remain distinct. There are many different control methods to keep species distinct and avoid outbreeding depression (where the hybrid between two groups is less fit than either of its parents). Changes in chromosome number generally results in speciation, and is especially common in plants, where polyploidy is thought to have been a major factor in plant evolution.

Chimps are NOT Monkeys!!! They are APES!

[enforcer999]

Gosh, that gets on my every last nerve! Apes are not monkeys and chimps are apes! Now I feel better. Thank you very much!

Re:Key line from TFA

[LunaticTippy]

Google "ring species" and you will see that this is well studied. There are salamanders, for example, that can interbreed with neighbors in a ring, but not with all other members of the ring.

Re: Why the need...

[Maxo-Texas]

quote: When I asked a professor point blank why the need for art and culture would develop through the course of evolution, he responded that he doesn't believe those traits would stem from evolution.

---
What was he thinking? Of course it stems from evolution.

Art may be the equivalent of stronger muscles for the mind. Artists may make it possible to do completely new and useful activities.

Or easier to understand bee dances- artists may figure out new ways to communicate ideas for the rest of the social group.

Or a peacock's tail- artists may have sex & reproduce more than non-artists.

Or just another way of gathering food. "Rich" members of society give food & resources to artists allowing artists to survive and reproduce. So artists are a successful symbiote or parasite on powerful or rich members of society.

---

Some things like "perfect" pitch or a "four octive range" are rare but basic talents run strong in some families just as talent for football runs strong in others.

---

As soon as a creature has the ability to be happy or unhappy (and even dogs can do this) then you can train them to behave differently without having to give them real food or resources. How is a painting of a rich patron that different from a pat on the head and praise to your dog that fetched the dead pigeon for you (or rolled over and played dead).

Art could start randomly-- a joke or story or picture that stimulates the brain of barely intelligent apes could definately have value (and cost to produce). Once it has value and cost, then it will be selected for or against by natural selection.

A worst case example- if you spend your people's grain to build a big statue of yourself, they may all starve and then you will be killed by them or enemy soldiers.

So art can vary from the little ruffle of yellow on the back of a bird's neck to the gaudy and expensive peacock's tail (and it does-- people somewhere probably died because of the money and resources spent on the orange gateway art project in central park).

Re:There won't be any controversy here!

[Whiney Mac Fanboy]

And I don't think the point of evolution is to create humans. I simply ask the question. Given the two types of evolution we teach, how do they explain the differences in how humans forked from this common ancestor?

1) Only one type of evolution is taught. It's split into two for the convenience of explaining things on small or large timescales (just like macro and micro economics are both just aspects of economics)

2) There isn't a specific explanation of why human evolution took a different path. It's just random. Sorry.

And having said debate numerous times over the years, no one has ever come close to answering that question once.

Hmmmn, sounds like you're making an argument from incredulity [cotch.net]

MISLEADING!

[posterlogo]

The blurb is very misleading. There was no "intercourse between humans and chimps" because THERE WERE NO humans or chimps back then. We did not evolve from chimps, humans and chimps simply had COMMON ancestry, a very long time ago. What this means is that the ancient ancestor of humans was able to, for a period of time, interbreed with the ancient ancestor of chimps. They were NOT that different back then. They may not have even looked very different. However, the genetic code was beginning to diverge because they had formed into two isolated populations, and then came back together briefly, before diverging forever into the lineages we can observe today. This "messy" split theory is still not entirely proven, but is an interesting analysis based on genetic sequence divergance data obtained from hundreds of specimens.

Re:There won't be any controversy here!

[Mr. Slippery]

Humans have some really unique aspects about us as a species. We have advanced language. We have art. We have complex emotions and psychology.

Other animals have language (not as advanced, obviously) [livescience.com], have been known to engage in artistic activity [abslogic.com], and appear to experience emotion [whozoo.org]. (Of course we can't say for sure - but then I can't say for sure whether you experience emotion either.) They also show culture, in the form of complex learned behaviors that differ from group to group.

When I asked a professor point blank why the need for art and culture would develop through the course of evolution

Evolution produces all sorts of things that are not "needed" for survival, like peacock tails.

Re:There won't be any controversy here!

[Anonymous Coward]

The long and short is this. Evolution occurs through one of two means. It is either a means of survival where the parent species is forced to adapt or die. Or evolution occurs through random mutations being passed on.

This shows that you do not have even a basic understanding of how evolution works.

So, they have had exponentially more generations than us, and survival wasn't an issue. When I asked a professor point blank why the need for art and culture would develop through the course of evolution, he responded that he doesn't believe those traits would stem from evolution.

He had no answer where they came from and he doesn't buy into creationism, but now we have this unanswered question. Something is very unique about humans and the evolution model does not seem to explain us very well.

What unanswered question? Why does art and/or culture exist? Evolution doesn't explain why anything, just how. If you want to know why anything, just continue believing in your holy ghosts and stuff.

Bah, evolution! Iluvatar created us all!

[Lispy]

As everyone knows the secondborn were created by Iluvatar and the Valar.
The interbreeding occurded in Angband where Morgoth created the orks and in Isengart where Saruman created the Urugh.
Are all songs forgotten since the Eldar left?

*sigh*

Re:Misleading

[Anonymous Coward]

When things branch they move off in different directions and the original species before the branch is lost.

There are circumstances where the original species is not lost either, such as when the new species evolved simply to adapt to a new region they migrated to and were trapped in. The species they evolved from can remain just fine in the original environment in such a case.

Re:Not to be too disgusting, but...

[Xibby]

No confirmed human/chimp hybrid has ever been found. Chuman/Humanzee/Manpanzee [wikipedia.org] and Oliver [wikipedia.org] would be good places to start if you want to find out more.

Re:There won't be any controversy here!

[spun]

You aren't understanding what I said at all, and I'm beginning to suspect that others have pointed out the same ideas to you before, and you didn't understand them then, either. Not understanding an answer is not the same thing as not getting an answer.

Let me try again. Fitness criteria do not apply across the board to all species equally. What makes a human fit for a human's niche is not what makes an ant fit for an ant's niche. Different niches, different criteria.

I'll ask you a question again, why don't humans have wings?

Re:You all have it wrong

[Anonymous Coward]

2005 called...

Re:There won't be any controversy here!

[spun]

It's no cop out, it's a fact. That's why they call it "Random Mutation." Selection is directed by fitness criteria, yes, but these criteria are random, because the particular environment a species finds itself in is random and changing. For instance, a crustacean is not likely to evolve wings (in one simple step, anyway) because it lives underwater and the selection criteria for it are different than those of say, a tree dwelling mammal. If the environment were to change sufficiently, that crustacean might face selection criteria that favored wings. Whether it developed them or not still depends on random mutation, but at least it would be possible.

So humans developed the traits you think of as unique to us because we happened to be in a random environment that favored those traits and because random mutation produced those traits.

Evolution is NOT random

[cutedinochick]

Well, the chaos thing doesn't work for a lot of people studying it. Evolution is not random. Mutations are random. The processes of evolution require that some mutations are more beneficial than others, and adaptation occurs when a population alters to the point of becoming better adapted to its environment. This may be morphologically or behaviorally. Evolution has a lot of genetic components (it wouldn't happen at all without genetic variation), but the environment is what the population has to adapt to. Remember, evolution acts on the level of species or populations, not at the level of genome, and it is anything but random.

Re:There won't be any controversy here!

[Whiney Mac Fanboy]

Don't believe everything you're told :-)

Mutations can be negative and positive - consider sickle cell anemia. its 'negative' unless there's lots of malaria in your area, in which case it's positive!

Read more at the Most mutations are harmful [cotch.net] Evowiki page.

Oh - and evowiki catalogues (and rebuts) most creationist arguments if you want to read up on them!

Re:There won't be any controversy here!

[whitehatlurker]

Chimps can paint too [bbc.co.uk], and better than I can, I have to admit. The dexterity of the forelimbs is the key adaptation, and was likely from the need to fling poo. (Not a comment on current painters.) The colour aspects are considered to be adaptations of vision needed to pick the best food sources.

I think your definition of culture might need some expanding - check out last month's SciAm [sciam.com] about orang culture. Their definition - roughly the ability to pass knowledge to the next generation - fits better, and if you were so inclined you may be able to fit that to your original ants.

Re:There won't be any controversy here!

[Winlin]

'A particular mutation can have a negative effect in one context, and a positive effect in another one. '

Such as Sickle Cell...it makes the individual less likely to die from malaria, but causes various other nasty problems.

Re:Hold it a second!

[sdfad1]

I don't know too much about chimp sexual habits, but we humans sure are a kinky bunch to boot.

No we're not, not even close. There are several (2? 3?) species of chimps, and they have distinct sexual behaviours. The most promiscuous chimp species is the Bonobo. In the bonobo, copulation is extremely common, and form the backbone of their social bonding fabric. See wikipedia [wikipedia.org], or read the Third Chimpanzee by Jared Diamond for example. Suffice to say, we humans are uptight conservative puritans by comparison.