A prehistoric worm with claws, says Live Science, has rewritten the origin story of crabs, spiders and mosquitos:
According to a new study of the creatures’ odd claws, Hallucigenia sparsa is the ancestor of modern-day velvet worms, which are strange, sluglike creatures with centipede-style legs.
The finding is surprising because it rewrites the evolutionary history of spiders, insects and crustaceans, said study researcher Javier Ortega-Hernandez, a paleobiologist at the University of Cambridge.
The ancient creature gets its name from the word “hallucination,” a moniker the worm earned due to its weird body. The animal’s head looks almost like its tail, and the creature has seven or eight pairs of legs as well as strange back-spikes.
The finding, detailed online yesterday (Aug. 17) in the journal Nature, puts Hallucigenia in the lineage of velvet worms, but disrupts the link between those worms and modern spiders, insects and crustaceans, a group known as arthropods. In fact, Ortega-Hernandez said, the new results suggest that arthropods are more closely related to another weird organism: the water bear, or tardigrade.
Might be worth remembering – arthropods are just bugs, but there’s a whole lot more of them than there are of us.