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It\u2019s been too long since we discussed whales, so this week let\u2019s learn about how whales evolved and some especially strange or mysterious whales!\n\nPakicetus was probably kind of piggy-looking, but with a crocodile snout:\n\n\n\nProtocetids were more actually whale-like but still not all that whale-like:\n\n\n\nNow we\u2019re getting whaley! Here\u2019s basilosaurus, with a dinosaur name because the guy who found it thought it was a reptile:\n\n\n\nHere's the skull of a male strap-toothed whale (left). Those flat strips are the teeth:\n\n\n\nAnother view. See how the teeth grow up from the lower jaw and around the upper jaw?\n\n\n\nA dead pygmy right whale:\n\n\n\nThe walrus whale may have looked sort of like this:\n\n\n\nThe half-beak porpoise had a chin that just would not quit:\n\n\n\nShow transcript:\n\nWelcome to Strange Animals Podcast. I\u2019m your host, Kate Shaw.\n\nThis week\u2019s topic is weird whales and some of their relations. If you think about it, all whales are weird, but these are the weirdest whales we know of. Some are living, some are extinct, and some\u2026are mysteries.\n\nWhales, dolphins, and porpoises are most closely related to\u2014wait for it\u2014HIPPOPOTAMUSES. About 48 million years ago an ancestor of both modern hippos and whales lived in Asia. It\u2019s called Inodhyus and it was about the size of a cat, but looked more pig-like. It was at least partially aquatic, probably as a way to hide from predators, but it was an omnivore that probably did most of its hunting and foraging on land.\n\nThe earliest whale is generally accepted to be Pakicetus. It lived around the same time as Inodhyus and its fossils have been found in what is now Pakistan and India. It was about the size of a big dog, but with a long, thick tail. Its skull was elongated, something like a short-snouted crocodile with big sharp triangular teeth. It had upward-facing eyes like a crocodile or hippo, and it also had four long, fairly thin legs. It probably hunted on both land and in shallow water, and like the hippo it probably didn\u2019t have much hair.\n\nThat doesn\u2019t sound much like a whale, but it had features that only appear in whales. These features became more and more exaggerated in its descendants. At first, these ancestral whales looked more like mammalian crocodiles. It\u2019s not until Protocetids evolved around 45 million years ago that they started to look recognizably like whales. Some protocetids lived in shallow oceans throughout the world but probably still gave birth on land, while others were more amphibious and lived along the coasts, where they probably hunted both in and out of water. But they had nostrils that had migrated farther back up their snouts, although they weren\u2019t blowholes just yet, reduced limbs, and may have had flukes on their large tails. But they still weren\u2019t totally whale-like. One protocetid, Rodhocetus balochistanensis, still had nail-like hooves on its forefeet.\n\nBy around 41 million years ago, the basilosaurids and their close relations had evolved, and were fully aquatic. They lived in the oceans throughout the tropics and subtropics, and their nostrils had moved almost to the location of modern whales\u2019 blowholes. Their forelegs were basically flippers with little fingers, their hind legs had almost disappeared, and they had tail flukes. They were also much bigger than their ancestors. Basilosaurus could grow up to 60 feet long, or 18 meters, and probably looked more like a gigantic eel than a modern whale. It was long and relatively thin, and may have mostly lived at the ocean\u2019s surface, swimming more like an eel or fish than a whale. It ate fish and sharks. SHARKS.\n\nSo when did whales develop the ability to echolocate? Researchers think it happened roughly 34 million years ago, which also happens to be about the same time that baleen whales and toothed whales started to develop separately. Echolocation probably evolved to help whales track hard-shelled mollusks called nautiloids. By 10 million years ago, though,