Giant ‘sea scorpion’ fossil discovered
The fossil of a previously unknown species of ‘sea scorpion’, measuring over 1.5 meters long, has been discovered in Iowa, USA, and described in the open access journal BMC Evolutionary Biology.
Dating back 460 million years, it is the oldest known species of eurypterid (sea scorpion) – extinct monster-like predators that swam the seas in ancient times and are related to modern arachnids.
Lead author, James Lamsdell from Yale University, USA, said: “The new species is incredibly bizarre. The shape of the paddle – the leg which it would use to swim – is unique, as is the shape of the head. It’s also big – over a meter and a half long!”
He adds: “Perhaps most surprising is the fantastic way it is preserved – the exoskeleton is compressed on the rock but can be peeled off and studied under a microscope. This shows an amazing amount of detail, such as the patterns of small hairs on the legs. At times it seems like you are studying the shed skin of a modern animal – an incredibly exciting opportunity for any paleontologist.” More.
Exciting opportunity indeed. The most interesting part is yet to come: What will the internal anatomy be like? Variations in external anatomy, while striking, don’t necessarily point to big changes or a very different life history: A recently discovered 425 million-year-old crustacean showed no significant changes in internal body parts compared to present day specimens. One researcher called it “a demonstration of unbelievable stability.” It’s only unbelievable if one takes Darwin’s dangerous idea seriously.
Note: I (O’Leary for News) will be writing about this type of “stasis” in a couple of weeks.
Meanwhile, see also: Talk to the fossils: Let’s see what they say back
Follow UD News at Twitter!