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I mention convergent evolution occasionally, but what is it really? This week we learn about what it is and some animals that demonstrate it. Thanks to Richard E. and Llewelly for their suggestions this week! Jaguars and leopards look so similar I\u2019m not 100% sure this picture actually shows one of each:\n\n\n\nThe adorable sucker-footed bat from Madagascar:\n\n\n\nThe equally adorable TOTALLY UNRELATED disk-winged bat from South America:\n\n\n\nMetriorhynchus looked a lot like a whale even though it was a crocodile ancestor:\n\n\n\nShow transcript:\n\nWelcome to Strange Animals Podcast. I\u2019m your host, Kate Shaw.\n\nThis week we\u2019re going to learn about some animals that represent convergent evolution. That\u2019s a term that I mention every so often, so it\u2019s time to really dig into it and see what it\u2019s all about. We\u2019ll start with animals that are fairly closely related, then work our way backwards to those that aren\u2019t related at all.\n\nBasically, when unrelated organisms develop similar form, structure, or functions as each other, that\u2019s called convergent evolution. One simple example is bats and birds. They\u2019re not related, but both can fly using forelimbs that have been modified into wings.\n\nThis topic idea was sparked by an idea from Richard E., who suggested an episode about evolution and how it doesn\u2019t \u201cimprove\u201d anything, just adapts. That\u2019s an important distinction. Evolution is a reactive force, not a proactive. Sometimes we use terms like advanced to describe certain animals, and primitive to describe others with traits that haven\u2019t changed in a long time. That implies that some animals are \u201cbetter\u201d than others, or better adapted. In actuality, one trait is not better or worse than another, as long as both traits help the animal survive and thrive. If an animal has traits that haven\u2019t changed in millions of years but it\u2019s still doing well, it\u2019s as adapted as it needs to be. An animal that\u2019s extremely specialized to an environment can sometimes be much more vulnerable to environmental change than a more generalized animal, too.\n\nFrom a scientific point of view, while it may look like species become more advanced as time goes on, all it means is that a lot of animals have evolved to occupy specific ecological niches. One example Richard gives is the panda, which we talked about in episode 42 about strange bears.\n\nThe panda is an extremely specialized animal. It\u2019s a bear that is no longer a carnivore, for one thing, and not only does it not eat meat, or hardly any meat since it will eat small animals and bird eggs when it finds them, it mostly just eats one type of plant. That plant, of course, is bamboo, which is low in nutrients. The panda has adapted in all sorts of ways to be able to digest bamboo, and one of the most obvious adaptations is what looks like a sixth toe on its forefeet. It\u2019s not a toe but a projecting sesamoid bone that acts as a toe and helps the panda grasp bamboo.\n\nBut the panda\u2019s sixth toe evolved because of selective pressures, because pandas born with the toe were able to eat more bamboo and were therefore healthier and more likely to have babies than pandas without the toe.\n\nRichard also mentioned the similarities between jaguars and leopards. They are related, but not closely. The jaguar is more closely related to the leopard than to the lion, but the leopard is more closely related to the lion than to the jaguar. That\u2019s not confusing at all. But both cats look very similar, tawny or golden in color with black spots called rosettes, and both frequently demonstrate an all-black coloring called melanism. But the jaguar lives in the Americas while the leopard lives in Asia and parts of Africa. Why do they look so similar?\n\nIn this case, a big part of the similarities between jaguars and leopards are that they share a common ancestor that lived around three and a half million years ago. The jaguar migrated from Africa into Europe and then into North America on the land bridge Beringia,