Eli5: Why are African and Asian elephants different genus despite looking so similar but species like Lions, Jaguars, and Tigers are the same genus despite being so much more physically and behaviorally different? Am I missing something? Just curious couldn’t find answers online
In: Biology
It all has to do with how closely related they are on a genetic level and how long ago they diverged into separate populations, not how similar they look. You can still breed tigers and lions today with moderate success due to their genetic similarity, while Asian and African elephants have never been recorded as creating a healthy offspring by mating.
For a counterexample, all of the different breeds of dog we have today diverged 30 to 40 thousand years ago. There is an incredibly wide range of appearances there, but they can pretty much all still mate with each other because their fundamental genomes are still pretty similar; we’ve just changed parts of it that code for outwardly obvious things like size and proportions. So they’re not even separate species yet, let alone different genuses, even though they look so different. Meanwhile the various cat species and elephants diverged 5 to 10 million years ago, or 5,000 to 10,000 thousand years ago to keep the same scale as the dogs. So depending on the situation, physical similarity and/or length of time since diverging from a common ancestor may not predict how genetically distinct different animal populations are.
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