Convergence| Day 64

Bodies are capable of a wonderful range of things that help them survive and thrive in the surrounding environment. We see with our eyes, we use legs to run away from predators, our skin protects us from toxic substances. We’re pretty well equipped to deal with a range of things!

Other animals have defensive measures of their own, such as giant spikes, bright colouring, or the ability to look like something else, mimicry.

We all evolved from a distant ancestor, branched, divided, dispersed in the world, while continuing to adapt to survive. To me one of the most fascinating concepts in evolutionary theory is convergent evolution.

It happens when unrelated organisms evolve to have a similar trait. After all, evolution doesn’t have a clear-cut path through the challenges of the natural world, it’s a complex interaction with the conditions surrounding the organism. Diversity comes from having a lot of different solutions for one problem, such as the range of mating dances birds can have.

Convergence, on the other hand, means that even geographically distant, unrelated animals stumble upon the same solution for something. The eye is a great example – vertebrates (think humans) and cephalopod mollusks (think octopi) have independently evolved camera-type eyes, a lens projecting an image onto a retina. However, while vertebrates focus by changing the shape of the lens, cephalopods do so through movement. The latter also don’t have corneas.

Image from here.
Image from here.

I love the idea that different organisms in distant parts of the planet could devise similar solutions to similar problems. Do you have a favourite evolutionary quirk?

Leave a Reply

Your email is perfectly safe with me.