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b"This week let's find out what lived before the Cambrian explosion!\\n\\nA very happy birthday to Isaac!\\n\\nFurther reading:\\n\\nSome of Earth's first animals--including a mysterious, alien-looking creature--are spilling out of Canadian rocks\\n\\nSay Hello to Dickinsonia, the Animal Kingdom's Newest (and Oldest) Member\\n\\nCharnia looks like a leaf or feather:\\n\\n\\n\\nKimberella looks like a lost earring:\\n\\n\\n\\nDickinsonia looks like one of those astronaut footprints on the moon:\\n\\n\\n\\nSpriggina looks like a centipede no a trilobite no a polychaete worm no a\\n\\n\\n\\nGlide reflection is hard to describe unless you look at pictures:\\n\\n \\n\\nTrilobozoans look like the Manx flag or a cloverleaf roll:\\n\\n \\n\\n\\n\\nCochleatina looked like a snail:\\n\\n\\n\\nShow transcript:\\n\\nWelcome to Strange Animals Podcast. I\\u2019m your host, Kate Shaw.\\n\\nIt\\u2019s the last week of August 2022, so let\\u2019s close out invertebrate August with a whole slew of mystery fossils, all invertebrates.\\n\\nBut first, we have a birthday shoutout! A humongous happy birthday to Isaac! Whatever your favorite thing is, I hope it happens on your birthday, unless your favorite thing is a kaiju attack.\\n\\nWe\\u2019ve talked about the Cambrian explosion before, especially in episode 69 about some of the Burgess shale animals. \\u201cCambrian explosion\\u201d is the term for a time starting around 540 million years ago, when diverse and often bizarre-looking animals suddenly appear in the fossil record. But we haven\\u2019t talked much about what lived before the Cambrian explosion, so let\\u2019s talk specifically about the Ediacaran (eedee-ACK-eron) biota!\\n\\nI was halfway through researching this episode when I remembered I\\u2019d done a Patreon episode about it in 2021. Patrons may recognize that I used part of the Patreon episode in this one. You\\u2019d think that would save me time but surprise, it did not.\\n\\nThe word Ediacara comes from a range of hills in South Australia, where in 1946 a geologist noticed what he thought were fossilized impressions of jellyfish in the rocks. At the time the rocks were dated to the early Cambrian period, and this was long before the Cambrian explosion was recognized as a thing at all, much less such an important thing. But since then, geologists and paleontologists have reevaluated the hills and determined that they\\u2019re much older than the Cambrian, dating to between 635 to 539 million years ago. That\\u2019s as much as 100 million years before the Cambrian. The Ediacaran period was formally designated in 2004 to mark this entire period of time, although fossils of Ediacaran animals generally start appearing about 580 million years ago.\\n\\nHere\\u2019s something interesting, by the way. During the Ediacaran period, every day was only 22 hours long instead of 24, and there were about 400 days in a year instead of 365. The moon was closer to the earth too. And life on earth was still sorting out the details.\\n\\nFossils from the Ediacaran period have been discovered in other places besides Australia, including Namibia in southern Africa, Newfoundland in eastern Canada, England, northwestern Russia, and southern China. Once the first well-preserved fossils started being found, in Newfoundland in 1967, paleontologists started to really take notice, because they turned out to be extremely weird. The fossils, not the paleontologists.\\n\\nMany organisms that lived during this time lived on, in, or under microbial mats on the sea floor or at the bottoms of rivers. Microbial mats are colonies of microorganisms like bacteria that grow on surfaces that are either submerged or just tend to stay damp. Microbial mats are still around today, usually growing in extreme environments like hot springs and hypersaline lakes. But 580 million years ago, they were everywhere.\\n\\nOne problem with the Ediacaran biota, and I should explain that biota just means all the animals and plants that live in a particular place, is that it\\u2019s not always clear if a fossil is actually an animal."