One of the topics I’ve been trying to learn over the past 2 years is genetics, genomics, and the biology of our body in general, including genes, traits exhibited by these genes, and various hormones that affect gene expression. So far I’ve reached a stage where I feel I know at-least what I should have been taught by 9th standard. Recently, while reading the book ‘The Cancer Code’, I stumbled upon the interesting concept of convergent evolution.
If you live in North India, you’ve probably eaten the fruit shehtoot (or mulberry). If you’ve visited a European country, you’ve probably also tried blackberries. While these 2 fruits have evolved separately, they share similar characteristics in their looks. This is a result of 2 different species evolving separately but in a similar direction, and is called convergent evolution.
Many thorny bushes and cacti looking plants evolve in different deserts. While genetically these are different, they have similar characteristics, because the conditions where they evolved were similar.
This trait of evolution, where different species evolve in a similar manner because of environmental pressures, despite not sharing genetic characteristics, is called convergent evolution.
Another example of convergent evolution is flying squirrels vs sugar gliders, 2 flying species of squirrels that have evolved on different continents, but look similar to the naked eye. It is similar to dolphins vs sharks — both have similar characteristics, but dolphins are mammals, but sharks are not.
Convergent evolution can also be found in certain foods — potatoes and sweet potatoes have very different origins, but they’ve evolved to develop a similar texture and look.
The one thing to remember about convergent evolution is that it is forward looking — ie. species evolve in a forward direction, so even though they may end up with similar characteristics, their genetics are different from each other. This is in contrast with Atavism, where the species under certain unfavourable conditions, evolve back ie — discard their recent evolutionary enhancements to revert back to where they were in evolution some time back.