A lot of otherwise intelligent and discriminating people have expressed that they don't believe in evolution. This
puzzles me a bit, because--as I hope you will find--the precepts of evolution are pretty much the most self-evident of
all well-known scientific theories. I can pretty much guarantee that, by the time you've finished reading this page,
and provided you're not some crazy kid who claims repeatedly that nothing is true.
The three core precepts of evolution are these:
- Offspring inherit the traits of their parents. So, two poodles will have a poodley puppy.
- The offspring of an organism is in some way different to the parents. Either because the two parents' traits have
'mixed' or because of a mutation.
- The more 'successful' organism (the one that is able to reproduce most efficiently) will triumph over the less
'successful' organism in terms of numbers or ubiquity.
And that's it. Are you convinced? No? I can't think why not, but let's go into some case studies that you'll be
familiar with:
- Purpose-bred Livestock: In England, as all of us rural folk will know, there are a number of different types
of cow. There are Jersey cows, Guernsey cows, and Friersian cows (and more!). These cows all have different
characteristics. For example, the Friersian cows are black and white, whereas the other two are brown. More importantly
to the farmer, they have different milk production. Jersey cows produce milk with high fat and protein content, but the
Friersian cows produce a lot more milk. This is due, at least in part, to selective breeding. The farmers of old would
take the cow with the kind of milk they wanted, leave it with a bull they rather liked the sight of (ideally the son of
a cow with the milk characteristics they wanted), and let them get down to business. They'd keep doing this over the
years, and eventually you'd end up with a cow essentially custom-made for our purposes.
- Purpose-bred Pets: Now, imagine the scene. Before humans were around, the cats were free. Black and white
cats bounding around the Australian bush, fellows with the Persian cats and the slightly-blue cats. Sound realistic?
Not really. Cats are predators, and to be a predator you need to be discrete. Having little white paws is a bit of a
giveaway. And what about those tiny cats you see? How would they get their food? Fact is, again, it's selective
breeding. This time, however, we've bred cats to be beautiful! Same with rats, dogs, and most any other kind of pet you
care to name. Can you imagine a pack of these
hunting and mauling to death a deer? I think not.
- The Flu: (I actually feel quite bad for that Indian woman... saying goodbye to all her ducks before they get
culled
) Anyway, the flu. There's a different one each year, that's how come you have to be immunised against it every
year, 'cause it's a slightly different virus. To all the creationists in the hall: do you think that's what god does
with his spare time? Make up a different flu virus every year? Somehow I doubt it :P The flu virus evolves every year,
goes through a slight mutation, so our immune systems can't recognise it. This is the same reason they ask you to
always finish a course of medicine rather than just stopping when you feel better (because it allows the germs to
mutate in your body, and thus create a strain of the disease the medicine can't help you with).
And that's it!
More complex evolutions, say the evolution of the eye, I can understand people being more skeptical about. But
hopefully now you can see that evolution does happen, if only on a very basic scale.
Feel free to post questions or suggestions in the comments.
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