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Deus ex Machina



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  • Darwins +23/-3

Yes! Yes! Now we are getting somewhere! Nice post!

In that link about the timeline of evolution it says that 1 billion years ago, there was multicellular life. Then 600 million years ago, there was simple animals.

So in 400 million years we went from clumps of cells on the ground to simple animals. How did that happen? That is mind-boggling.

As it happens, the phenomenon you describe (though a great deal of life was aquatic, so "clumps of cells on the ground" is probably not a good description) is thought to have occurred in the space of around 80 million years, from 580-500mya (the "Cambrian Explosion"). A significant development in the intervening period is the formation of the ozone layer. Another that is thought to have occurred is a global glaciation event. Either, or both, may have contributed to this. I'm not personally that familiar with the Cambrian Explosion to say much on it, though the Wikipedia entry looks like it's worth perusing.

They are still dogs though. That's the point. We accept this already. We know small changes can even form a new species of dog that can't mate with the other dogs.

But the main point is that they are still dogs. This is not empirical evidence of macroevolution.

It sounds like we need to address a misconception here.

We need to be clear about what evolution says, and - importantly - what it does not say. Evolution is descent with modification by means of natural selection.

Note the key word there: descent. This is really important, because what this means, and what evolution actually says, is that one can never escape one's ancestry. And biological classification of animals is all about ancestry.

There was once a BBC Television comedy series called "Red Dwarf", in which one of the members of the crew is a member of Felis sapiens, a humaniform species descended from domestic cats. After the other crew members, Rimmer and Lister, discover The Cat, Lister asks Holly for an explanation of what they have just seen:

Lister: Holly, what was that?
Holly: During the radioactive crisis, Dave, your cat and her kittens were safely sealed in the hold; and they've been breeding there for three million years, and have evolved into the life-form you just saw in the corridor.
Lister: I don't get it.
Holly: Well, you know how mankind evolved from apes...
Lister: Yeah, I know that.
Holly: He evolved from cats. His ancestors were cats; he's descended from cats; he is a cat.

What this means is that of course any descendant of a dog will still be a dog - just as it will still be a member of the order "flesh-eaters" (carnivora), and it will still be a mammal, a therapsid, a chordate, an animal and a eukaryotic life-form.

That's definitional. It's a matter of cladistics, and of ancestry - which, in biology, happen to be pretty much the exact same thing. For any descendant of a dog not to be a dog would be a contradiction in terms.

If you think "macroevolution" entails the descendants of dogs one day being something other than dogs, then your notion of "macroevolution" isn't anything to do with evolution at all. They can no more not be dogs, than can any descendants you may have not have you as an ancestor. You would not say "prove to me that 2 = 9, or I will not accept mathematics", would you?
Changed Change Reason Date
Jag excellent job clarifying a head-banging misconception November 04, 2013, 09:28:01 PM
jaimehlers That's a really good point. November 04, 2013, 09:22:55 PM