Headphones on 12/3/2006 at 03:58
Quote Posted by jay pettitt
Go catch a fruit fly.
an evolutionary kissoff! classic :)
Convict on 12/3/2006 at 04:03
Quote Posted by d0om
However, when carbon fixing bacteria first evolved, there was no O2 in the atmosphere. From looking at ice cores in the south pole they can see what the atmosphere was like in the past. This meant rubisco was a very efficient enzyme when it evolved. However after photosynthetic life became rather dominant the O2 concentration increased and the atmosphere became oxygen rich.
It is this evolutionary history which we are stuck with!
I'm sorry, you seem to have made an assumption that carbon fixing bacteria did evolve (and from what do you mean - another bacteria or something else?). Could you please elaborate for me on the evidence showing that the bacteria did evolve - or are you just assuming it must have to exist?
Quote:
I think the hypothosis I just put forward for the evolution of mitochondria and rubisco makes a lot more sense than any intelligent design hypothesis ever could. It isn't neccesarily fact, but it is the best idea we have given our current evidence and understanding.
And its teh sexy :)
But there's no specific data one could look for that would show it to be false?
Quote Posted by Nicker
Very simply put - a species is a group of individuals that can produce viable offspring. Members of a subspecies (equivalent to breeds in domestic animals) may produce viable offspring but will not normally do so in the wild. This may be because the populations are physically isolated or because their morphology and / or behaviours disuade them from attempting to mate. Domestic breeds are 'isolated populations' owing to our control of their breeding choices. And while it is unlikely that a chihuahua and a great dane could get it on effectively, they are still genetically similar enough that their puppies would be viable.
My point about the dogs is that artificial selection produces much more variation than natural selection (since humans care for dogs that might well die in the wild) and so much more "evolutionary" pressure should have been exerted via artificial selection than via natural selection in producing something genetically different enough to make a new species. An example (sort of mentioned before) is a mutated fruit fly that would die very rapidly in the wild but is able to live under artificial selection environments.
Quote Posted by GBM
[Evolution is a testable theory], and yes you can. Why do you think bio labs have a hard-on for fruit flies, dinkus?
Fruit flies are a very interesting experiment IMO. You can merge tens of thousands of years of breeding for most other creatures into relatively short time frames for fruit flies. Apparently scientists make this even more exaggerated (I can only guess how many millenia of breeding it compares to in most animals) by using x-rays and stuff. I do wonder that while they have managed to do a lot of mutating they haven't produced the large changes that I would expect to see if it was an animal changing into a new animal - what is the (suggested) time frame for animals changing into new animals in the wild?
jay pettitt on 12/3/2006 at 04:14
Quote:
But there's no specific data one could look for that would show it to be false?
You could look for evidence of intelligent design...
SD on 12/3/2006 at 04:19
Quote Posted by nickolae
the reptile to mammal deal. Where is that? no where.
Australasia, actually.
Inline Image:
http://upload.wikimedia.org/wikipedia/commons/5/55/Ornithorhynchidae-00.jpgYou're evidently not very well-educated, so let me explain. What you are looking at is a Duck-billed Platypus (
Ornithorhynchus anatinus). It's a mammal, but it doesn't give birth to live young, like humans or cats do. It lays eggs. It's one of five closely related species of mammal that lay leathery eggs, much like reptiles do. It also possesses an opening known as a cloaca, which isn't found in me or Tiddles, but which
is found on reptiles, birds and amphibians.
What's the significance of this bizarre creature? Well, either it's one of those reptile to mammal jobbies that you're insisting doesn't exist, or it's some hilarious practical joke being played by the big guy upstairs.
Nicker on 12/3/2006 at 04:34
Quote Posted by Convict
My point about the dogs is that artificial selection produces much more variation than natural selection (since humans care for dogs that might well die in the wild) and so much more "evolutionary" pressure should have been exerted via artificial selection than via natural selection in producing something genetically different enough to make a new species.
Ye gods man! I addressed that very point in the paragraph prior to the one you quoted!
"Nicker: Given a few hundred thousand years it is possible that certain breeds of dogs could become distinct species but given that domestiation is only a few thousand years old the fact that we have produced to (sic. should read NO) new species in no way disproves evolutionary theory."
A few HUNDRED THOUSAND years. Maybe even millions of years.
But I refer you again to this link provided by Fafhrd - scroll down to 5.0 Observed Instances of Speciation. It may not have happened in dogs but it has happened in other things.
Aerothorn on 12/3/2006 at 04:36
Ok, I know I'm not supposed to poke my nose in and make annoying little 'play nice' posts, but I do want to point out: if you could ever convince anyone of anything over the internet (and I think it is possible, it's just obviously a lot harder to do so in online forums) you're probably not going to do it by attackin people - that just makes folks get all defensive and feel morally superior.
Convict on 12/3/2006 at 04:38
So what species precedes and what species follows the platypus?
RyushiBlade on 12/3/2006 at 04:42
It has been hypothesized that mammals evolved from reptiles who, in turn, evolved from Amphibians, yes. But remember that at the time, they weren't mammals as seen today. Rather, they could best be described as slightly hairy reptiles. It took a bit longer for mammals to diversify.
Hey, bit of a tidbit of brainfood for you guys, since I'm mildly interested in this stuff.
Dinosaurs aren't actually reptiles. You'll note that all reptiles have their legs splayed out to the sides, such as the alligator. This is true for every reptile. Dinosaurs, though, had a more highly evolved pelvis so their legs could support their huge weight. They were beneath their bodies, not to the sides.
So really, it's more likely we evolved from early dinosaurs who evolved from early reptiles themselves.
(I also find it strange ALL dinosaurs became extinct. We have all these different groups of animals today - mammals, birds, fish, reptiles, etc. - and dinosaurs belong to their own unique group. It could be the only other group to ever exist, and yet every single representative from that group has gone extinct while all others survived. Even taking into account the evolution of dinosaurs into birds, it's still very strange.)
Oh, and there are no transitional forms because of Darwin's Survival of the Fittest law. In some cases, a lesser evolved form of a creature can survive in isolation, but most of the time this is not the case. Humans, for example, killed off the Neanderthal. We also killed off other sub-species of ourselves as we progressed and became smarter.
Erm. :erm:
Don't quote me on anything.
SD on 12/3/2006 at 04:45
Quote Posted by Convict
So what species precedes and what species follows the platypus?
Nothing follows it, it's an extant species.
What precedes it are ancient and extinct varieties of platypus. The platypuses branched off the mammalian tree early in the development of mammals, and for whatever reason, they retained a number of reptilian features. Go back far enough, and platypus's ancestors are our ancestors - except we stopped laying eggs a loooong time ago. They didn't.
Convict on 12/3/2006 at 04:48
Quote Posted by Strontium Dog
What precedes it are ancient and extinct varieties of platypus. The platypuses branched off the mammalian tree early in the development of mammals, and for whatever reason, they retained a number of reptilian features. Go back far enough, and platypus's ancestors are our ancestors - except we stopped laying eggs a loooong time ago. They didn't.
Are you making stuff up or do you have evidence of this?
