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beezlebub33 t1_j5jf1c4 wrote

While it's theoretically possible, it's unlikely.

First, organisms evolve based on mutations and differential reproduction, so you would need the same sorts of mutations and the same sort of selection pressures. Both of these are unlikely, the conditions just are not the same. Also, why did D go extinct? Because they died out because of over competition in their niche, some parasite, etc. ; well, it would affect a new D too. And of course mutations are random, so it's pretty much impossible to exactly replay.

That said, we do have lots of examples of convergent evolution, where different organisms have evolved to fill in niches in different areas. See: https://en.wikipedia.org/wiki/List_of_examples_of_convergent_evolution . Let's say there is a land that doesn't have a large diversity of birds (say, the Galapagos). The first birds that arrive will radiate (diversify through evolution) to fill lots of different niches, such as eating nuts, eating fruits, eating insects, even though they had the same progenitor species. Interestingly, the evolved organisms filling the niche don't do it quite the same way, because evolution adapts what is at hand.

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espressocycle t1_j5jg4ad wrote

Replying to beezlebub33 (#1,449,974)

Not to mention if a species became extinct due to natural forces those would preclude evolving into that form in the first place. That wouldn't necessarily apply to human-caused but they are too recent to know.

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Any-Broccoli-3911 t1_j5jhmr0 wrote

First, all animals evolve at a similar pace. If you got A->B->C->D, then D got extinct, A, B, C won't exist anymore, so there's no C to evolve back into D.

Second, mutations are random and the number of possibilities is extremely large, enough that we can consider it almost infinite. So the probability to have mutations that bring back the same species that got extinct before is almost 0.

What does happen is convergent evolution in which a species evolve to be morphologically similar to another species (extinct or not) because they occupy a similar ecological niche (what they eat and the environment they live in). Though they are morphologically similar, they'll still be as genetically different as expected for species that diverged when they did. They'll still have a lot of differences due to those genetic differences.

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thebedla t1_j5jjlho wrote

This has been observed, it's called iterative evolution or Lazarus taxon or Elvis taxon.

Note the rationale behind renaming Lazarus to Elvis is to allude to impersonators and clarify that it is not actually being reborn. Given how much genetic information there is, superficially "the same" species (such as the "re-evolved Aldabra rail) will still be different genetically.

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amarillion97 t1_j5k27pd wrote

The amount of random chance involved means that it is practically impossible.

Besides that, the course of evolution of one species is influenced by species in the surrounding ecosystem. Symbionts, competitors, parasites, diseases etc. that were present when C evolved to D all have an influence. But those species have also evolved in the mean time. The exact same conditions will never arise again.

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remimorin t1_j5k9j0s wrote

People have already answered. I would like to add, see convergent evolution. Same évolutive pressure results in similar response (results). But similar is important not the same. As there never have been 2 deck of cards shuffled identically (given they were well shuffled), you will never get exactly the same thing.

How similar things can be? See barracuda and muskellunge, carcinization to begin with! Thyalcine and canids.

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Flendarp t1_j5ll5ax wrote

It has happened many times. The crab has been evolved into several times throughout history. Rats and mice are not even closely related. Of course, it's not the same exact species each time but similar enough to be considered almost the same to most people.

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Person012345 t1_j5lti2r wrote

  1. even if you start with the same animal, the random processes that make up evolution are vanishingly unlikely to produce the exact same end result twice when it's working with such an immense thing as the genetic code.
  2. Other animals may well move in to occupy the niche that D occupied, if indeed the niche itself even exists any more (which it may well do again at some point).
  3. C rarely continues to exist unchanged. There are some animals we think of as ancient but even those are rarely the exact same as they were 50 million years ago and even aside from that in the vast majority of cases C simply no longer exists in any form. I mean say humans went extinct next week. We look back to our last common ancestors with chimps: Gone. With gorillas? Gone. With other primates? Gone. I doubt there is a single extant animal (or any other kind of life) we can directly trace our lineage back to to give humans "another try" 5 billion years down the line. The same is probably true of most animals.
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junegoesaround5689 t1_j5rypyu wrote

Evolution doesn’t (and can’t) "retrace its steps". So, almost certainly this would be impossible. It would be like two different rainstorms producing exactly the same raindrops falling in exactly the same places with identical lightening and thunderclaps. Waaaay too many variables for the exact thing to happen twice. Similar (ref convergent evolution), yeah, but not identical.

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science_lake_ocean t1_j5utopu wrote

If selective pressure and genetic diversity support it then evolution proceeds (realizing that actual speciation may also require isolation of a sub-group). However, the underlying premise of a linear process is not how evolution works.

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