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b"This week's (short) episode is about two animals that should have been in the strangest small fish and weird pigs episodes, respectively. I left them out by accident but they're so interesting that they deserve an episode all to themselves anyway. Thanks to Adam for suggesting the mangrove killifish!\\n\\nFurther reading:\\n\\n25 Years in the Mud: How a Quirky Little Fish Changed My Life\\n\\nThe mangrove killifish just looks normal:\\n\\n\\n\\nNot a unicorn pig (okay yes technically a unicorn pig):\\n\\n\\n\\nUnicorn pig skull:\\n\\n\\n\\nShow transcript:\\n\\nWelcome to Strange Animals Podcast. I\\u2019m your host, Kate Shaw.\\n\\nA few weeks ago we had an episode about strange small fish. Shortly after that episode released, I was going through my disorganized ideas and suggestions file and realized I\\u2019d left out one of the best weird small fish ever, a suggestion by Adam. I also discovered I\\u2019d missed an extinct pig I\\u2019d planned to include in the recent weird pigs episode. So let\\u2019s play catch up in a short episode and learn about both this week.\\n\\nThe fish Adam suggests is called the mangrove killifish, also called the mangrove rivulus, which lives in parts of Florida and Mexico, down to Central and South America. It\\u2019s technically a marine fish, meaning it lives in salt-water, but it also likes brackish water, that\\u2019s less salty than the ocean, and occasionally it even lives in freshwater. It especially likes mangrove swamps. It grows up to 3 inches long, or 7.5 cm and is a mottled brown in color with an eye spot on its tail. It doesn\\u2019t look like anything special.\\n\\nBut the mangrove killifish has a lot in common with amphibians, especially the lungless salamanders. Many types of salamander absorb air through the skin instead of through lungs or gills. The mangrove killifish does this too. It often lives in abandoned crab holes, which may not have very high quality water. But that\\u2019s okay, because it can absorb air through its skin and can live out of the water for well over a month as long as its skin stays damp. It\\u2019s sometimes found in places where you wouldn\\u2019t expect to find a fish, like the inside of rotting logs or buried in damp dead leaves.\\n\\nSo how does the killifish get into the rotting logs or the leaf litter or the crab burrows that aren\\u2019t connected to waterways? It actually uses its tail to flip itself out of the water and onto land, and then it continues to flip here and there until it finds a place where it wants to live for a while. It can direct this jumping, not just flop around like most fish out of water, and can jump several times its own length.\\n\\nA lot of times when the tide goes out, fish get trapped in crab holes, dimples in the sand or mud, and other shallow water. That\\u2019s okay if the tide comes back in far enough to re-submerge the holes, but if the water doesn\\u2019t quite reach, it\\u2019s not long before fish start to suffocate as all the oxygen in the water is used up. But the killifish doesn\\u2019t have that problem. It just flips itself out of the water. It can also leave the water if it gets too hot.\\n\\nThe killifish is also territorial in water, which requires a lot of energy. When it\\u2019s out of the water, or in a little temporary pool or a crab burrow where it doesn\\u2019t have to worry about other killifish, it can relax. On the other hand, it loses a lot of weight while it\\u2019s out of the water since it doesn\\u2019t eat as much. So there are trade-offs.\\n\\nEven the killifish\\u2019s eggs can survive out of water. The fish usually lays its eggs in shallow water, sometimes even on land that\\u2019s just near water. The eggs continue to develop just fine, in or out of water, but they delay hatching until they\\u2019re submerged.\\n\\nAnd that leads us to the most astonishing thing about the mangrove killifish. In most populations, almost all killifish are females, and most of the time they don\\u2019t need a male fish to fertilize their eggs. Females produce eggs but they also produce sperm that fertilize the eggs before they\\u2019re even laid."