Tuesday, July 01, 2008

Monkey's Uncle

One hundred fifty years ago today, Charles Darwin and Alfred Wallace announced their theory of evolution by natural selection. It would be another year before Darwin published the definitive book on the subject, which is when everyone would notice said theory.

What's interesting is that the idea that species evolved over time was pretty well accepted by the biological community back then - but when it concerned the "how," people were mostly subscribing to a "great chain of being" theory or an "acquired characteristics" theory (most famously articulated by Jean-Baptiste Lamarck). Darwin provided a better answer, and it has stood up to scrutiny for 150 years now - aided greatly by the work of a contemporary, Gregor Mendel, whose work in genetics would go unnoticed for decades after its completion in 1865. Scientific notoriety is a fickle beast sometimes...

Also, in unrelated culture-war stuff, this is awesome. My favorite line: "After the race, Homosexual and Dix looked at each other and slapped palms, then hugged." Autoreplace: Not all it's cracked up to be.

5 comments:

Matthew B. Novak said...

I'd have gone for a title of "Monkey's Nephew"...

I thought evolution had been around longer than 150 years. I wonder how species have changed in that 150 years, if at all. I suppose for some that's a lot of generations and for others it isn't. I guess that's the relevant measure, right?

Jeff said...

Yeah, generations are the important measure - which is why biologists love to use fruit flies to do experiments on genetics and evolution. They mate and die in, like, four days.

It's tough to see macroevolution because it happens so slowly. The best thing I can think of for seeing evolutionary pressures at work is in bacterial resistance to antibiotics - by using antibiotics, we're essentially "selecting" for those bacteria who have a mutation which gives them resistance to said antibiotics. And it really annoys me that people talk about antibiotic resistance in Lamarckian terms, i.e. "the bacteria developed a resistance to..." No, they didn't "develop" a resistance, all the bacteria that had a resistance just survived and reproduced.

Matthew B. Novak said...

I just happened to discuss evolution yesterday with a guy who doesn't believe it. He's not convinced because there's no explaination for how and/or why mutations happen.

I don't know if that's true, so I didn't have much to say on it. Anyone?

Jeff said...

Generally, mutations are the result of transcription errors when DNA is being replicated. Generally, nucleotide deletion or insertion results in nonsense proteins and it never gets off the ground, causing the gene to be rendered useless. Nucleotide replacement can be benign (i.e. the DNA ends up coding for the same protein anyway) or can result in a different amino acid, creating a protein with different characteristics.

We don't know specifically what causes mutations, as far as I know. But that seems like a lame reason to discredit evolution. Kinda like saying a car doesn't work because you're not sure how the radiator is made.

Michael said...

I saw that Tyson Gay article... Very, very funny. My favorite line:
"It means a lot to me," the 25-year-old Homosexual said. "I’m glad my body could do it, because now I know I have it in me."