For me there has always been a huge flaw in the arguments condemning natural selection — the fact that it works. You can talk all you want about creationism, or intelligent design, but natural selection is based on plain and simple observation of nature at work. So many times the argument you hear from people is that, "I'm not descended from some monkey, God made me," which has little or nothing to do with natural selection. Even if it turns out that a Creator was involved with the design of the human species millions of years ago, it has nothing to do with whether natural selection as a process works or not.
For those of you who missed grade ten biology, I'll give you a little summary of how evolution works, okay? The first thing you have to realize is that it's all about genetics and errors in genetic code called mutations. Now don't go confusing mutation with the Marval comics title The X-Men version of mutants, because in nature a mutation can be something as subtle as a colour change in feathers or fur.
Mutations occur all the time in all species, but usually they have little or no impact on that species and the strain dies out because the carrier of that new genetic code doesn't survive, doesn't mate, or its progeny don't make it. But once in a while a genetic variation comes along that is able to do better in the environment it finds itself in than other members of its species.
Whether collecting food or hiding from predators, its deviation or mutation gives it a better shot at surviving and when it breeds, that gene is passed along to some of its offspring who in turn… well you get the picture. As this happens the members of the species who lack the mutation that either keeps them safer or allows them to eat different foods, start to die out because they can't compete and gradually that gene pool is effectively eliminated as the dominate one; hence the saying "survival of the fittest."
That was more or less the theory Darwin put forward after his infamous voyage on the HMS Beagle took him to the Galapagos Islands. Darwin's wasn't the only theory of evolution to come out of the 19th century. Jean-Baptiste Pierre Antoine de Monet, Chevalier de Lamarck proposed that animals would evolve because of their surroundings and that genetic changes would occur as they attempted to adapt to what was around them.
Article comments
1 - duane
Good stuff there, Richard. I didn't miss 10th grade biology, but I've had many, many years to forget it. Thanks for the review. I'm reminded also of how unlikely it is (or was) that birdwatching could have turned into a revolutionary scientific theory.
2 - Serket
I like reading about evolution and have a interest in genetic genealogy. I am probably kind of an anomaly as I am also a non-religious conservative Republican.
3 - duane
Amazingly enough, evolution is not affected by your political leanings or your religious beliefs. Just ask the finches. From the raving, judgmental, fundamentalist finches all the way across the spectrum to the immoral, heartless, godless finches, evolution just keeps on working.
4 - Odin
It's not a huge flaw just a teeny question about adaptations. Obviously they occur, but why? Who or what is responding? Is the response inherent in the genes in the cells of the finch? How do they know how to respond, buried as they are microscopically in the flesh? What overview can they have?
5 - duane
Mutations, as explained in Richard's article. The organisms are imperfect.
6 - Victor Plenty
All organisms are imperfect. Some are more imperfect than others.
7 - duane
Present company excluded, of course.
8 - Odin
Imperfect or not, why the drive to survive? Why don't all organisms just give up under adverse pressures?
9 - duane
The drive to survive? You mean why does it seem like some kinds of trees found in tropical rainforests are compelled to grow tall enough to reach sunlight? Do you think that trees have an inherent survival instinct?
I feel like I'm being maneuvered.
Why don't all organisms just give up under adverse pressures?
By "give up," you make it sound like a matter of choice. You might look up the Arcaca tree to see some adaptive changes under environmental stress, where the stress is provided by giraffes' tongues. I think you will agree that the trees didn't figure this out for themselves.
10 - Victor Plenty
Some individual organisms do give up under adverse pressure. If they give up and die before they have time to reproduce, that particular trait does not get passed on to a new generation.
Whatever genetic combination might produce a "drive to survive," it will be highly likely to spread throughout the population of any species that develops it.
Occasionally a few individuals may lack any form of survival instinct. That makes their branch of the species far more likely to die out. If they die before producing offspring, they don't make any difference to the overall evolution of the species.