I used this picture in an earlier article — forgive me. It is just so appropriate to this topic. Anyway, that particular Homo sapiens hugging the dolphin carries my genes into the future.
Speaking of genes, researchers have caught a dolphin with residual back legs. I chose this particular article over the others because it is, well, asinine. I am not particularly empathetic with the excesses of the animals rights movement, but this article makes abso-fricken-lutely no sense. The author lost me immediately when she suggested that these fins will somehow “prove mammals know more than animal rights activists about the Animal Kingdom.” Correct me if I am wrong, but animal rights activists also give birth to live young and then nourish them with breast milk. If you send her an email, please, be nice. Don’t reinforce her warped image with aggressive and rude diatribes (like this one). God help her, she obviously just isn’t that bright.
This makes the news because people seem to be drawn to oddities like two-headed turtles. I mention it because it makes such a beautiful example of how evolution works. I have debated religionists a few times on the topic of intelligent design. It is every bit as fruitless as you would expect any debate on religion or politics would be. But one thing always eventually becomes apparent. My opponent does not have a good understanding of the theory. They don’t seem to grasp the immensity of time or the mechanisms involved.
If those back fins gave this dolphin a competitive advantage, and if the gene expression that created them is dominant, we would start to see more and more of them — this one particular dolphin and its descendants would have slightly more offspring than dolphins without four fins. Given a small reproductive advantage and a lot of time, this species of dolphin would replace the one that spawned it.
Because most organisms are finely tuned to survive in the environment in which they evolved, a random genetic expression like this almost always imparts a fatal or a slight reproductive disadvantage. However, when the environment changes, it puts stress on the organisms to survive and creates an opening for mutations like this one to take hold and send the species into a period of change.
Let’s just assume for the sake of demonstration that these extra fins cause Japanese dolphin harvesters to let these dolphins go, for whatever reason. Let’s also assume they somehow assist some dolphins to wriggle out of a net before drowning. The thing in the environment that is forcing change is a super predator let loose on the oceans — human beings. Mega-changes in the environment like this may explain Gould’s punctuated equilibrium theory. However, if the change in the environment is too big, and if it happens too fast for organisms to adapt via evolution, you don’t get speciation — you get a mass extinction. Humanity is changing the planet in a wink of the geologic eye.