The Cambrian was the Age of Weird. True, this is a bias that stems from considering the modern world’s organisms as “normal”, or at least familiar, but it’s difficult to look at some of the world’s first animals without seeing evolutionary oddities that held the potential for an array of unrealized alternate histories for life on Earth.

For example, it took 14 years for paleontologists to realize that they had been interpreting the spiny, 508 million year old Hallucigenia the wrong way up, and it was just last week that researchers finally resolved which end of the invertebrate was the head. Now, hot on the heels of that announcement, Yunnan University paleontologist Jie Yang and colleagues have