Hi! Interesting thread
I was wondering if anybody could help me understand the following:
Evolution is generally considered to not involve any sort of intelligent purpose - beyond a drive to survive as a species, and as an individual (where it aids species survival). I mean this by contrast with those who say that life forms, and their existence, is driven by some sort of intelligent design and plan. Obviously there are some things that don't fit that general description, or at least it isn't immediately obvious that they do.
The thing I don't get involves Polar Bears.
Snow is white. Polar Bears are also white (or at least nearly white). This is supposed to be a physical trait that aids their survival - the near whiteness makes it difficult for other animals to see them, so they can sneak up on their prey and kill and eat it, thus they get energy and can stay alive, which means they can reproduce e.t.c.
Polar Bears haven't always existed, according to evolutionary theory. Neither has snow (on Earth at least), according to whoever studies that - geographers? - and tells us about the formation of the Earth from molten rock and all that.
However, snow existed before Polar Bears did.
So, according to evolutionary theory, we can tell a story about how Polar Bears evolved from another bear-like creature, that moved into snowy regions, and over a long period of time some creatures born with whiter coats were better able to survive because of their ability to ambush prey, and so bred more successfully. Eventually we have the Polar Bear, a creature that has a physical trait that aids it's survival in that particular environment.
The bit that I'm having trouble understanding is this:
How did the Polar Bear become white? Why did it become white? The way I understand evolutionary theory, it would be random mutations and the greater chance of survival for those with white(r) fur. So were there also mutations that resulted in Polar Bear ancestors with red, or purple, or green fur? And these ones died out because they weren't as successful at hunting?
That sounds rather impossible. If it is true that the Polar Bear evolutionary line includes some (extinct) creatures with red, purple, or green fur, then it would make sense to me. But I don't think that that is true.
Is evolution (and I know its wrong to speak of it as sentient, but its the only way to make my confusion clear) aware that snow is white? The Polar Bear ancestor gradually evolved into a white animal, and snow (it's environment) is white. The only way I can see evolution as random (not truly random since there is the goal of species survival) here is either:
1) There has also existed Polar Bear-like creatures with every colour of fur possible (because the random mutations of genetics cannot be aware of what colour snow is).
2) There is intelligence, or design, in evolution. The environment is white, therefore the bear becomes white. Evolution somehow makes a judgement about the environment (can discern between colours), and adapts accordingly. Snow is not orange, but presumably evolution doesn't know that.
Could someone please explain this to me? I'm guessing I'm maybe misunderstanding evolutionary theory, or not getting it properly, but this to me just doesn't make sense.
Thanks in advance!