There have been demonstrations of ecomorphs in different taxa, where each morpho

Question

There have been demonstrations of ecomorphs in different taxa, where each morphology type is associated to a single environment. I know that it happens because special morphological characters increase the fitness and therefore will be positive selected.

My question is; if we find similar places (talking about natural pressures and climatic conditions) on earth and given enough time, can we expect to see more or less the same ecomorphs living in different places? Also, assuming that, could evolution be a regarded a non-stochastic process?

Explanation / Answer

The phenomenon you describe, where the same result comes about in more than one time/location via evolution, is called "convergent evolution." It is when the same character, or trait, evolve independently of one another. One example is the wing, it has evolved (at least) several times independently, in bats, birds, and insects. Parallels can also be drawn with other traits like dispersion methods of seeds, or the evolution of fins in fish, dolphins, and whales. Here is a classic paper by Ernest Williams from 1972 which describes one of the earliest examples given of ecomorphs, the anolis lizard, also talked about on this site.

This is from a good article on the new scientist website that would be worth reading:

"Evolutionary convergence occurs at every level, from proteins to societies. An unusual antibody once thought to be unique to camels has a close equivalent in sharks, for instance, while naked mole rats form social colonies like those of ants and bees.

"What this means is that if we could wind the clock back and let life evolve all over again, life might take very different paths but still produce organisms that, in some ways, resemble the organisms alive today.

"There would almost certainly be streamlined swimmers in the oceans and winged creatures in the skies. In fact, some argue that the evolution of intelligence is also virtually inevitable, though intelligent organisms could be very different from us."

The answer to your question is yes, with enough time and the same selection effects we would not be surprised if there was a similar pair of independently evolved characters. However, selection acts on random mutations which is not a directed process, therefore for the same characters to evolve you would need mutations to occur that had similar effects. This is why given enough time we can see the same responses. Despite the non-random effect of selection, we could consider evolution to be a stochastic process, it only arrives at the same converged point by chance. This is because selection (the main driver of evolution) acts on randomly generated genetic variation thus the direction of the evolutionary trajectory is random.

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