Arachnophobes of the world, this is where it all started.
Roughly 410 million years ago, the trigonotarbids walked the Earth. One of the first land predators, the now-extinct order of arachnids are an ancient relative of modern spiders (though not a direct ancestor). Trigonotarbids died out around 300 million years ago, but in their heyday these were “top dog of the food chain,” according to palaeontologist Russell Garwood in a press statement from the University of Manchester. In a new study, Garwood and colleagues have tried to recreate the arachnid's gait. The creepy crawly creature in the video above is the result.
In the 1920s, scientists dug up pristine trigonotarbid fossils just a few millimeters long from a site outside the Scottish town of Rhynie. Using modern techniques, Garwood and his colleagues studied the incredibly well-preserved fossils, reproducing the structure of the arachnid's legs, says Jonathan Amos for the BBC. In an interview with Amos, Garwood explained how they turned the arachnid's anatomy into motion.
"We could see the articulation points in the legs," explained Dr Garwood.
"Between each part of the leg, there are darker pieces where they join, and that allowed us to work out the range of movement.
"We then compared that with the gaits of modern spiders, which are probably a good analogy because they have similar leg proportions. The software enabled us to see the centre of mass and find a gait that worked. If it's too far back compared to the legs, the posterior drags on the ground. The trigonotarbid is an alternating tetrapod, meaning there are four feet on the ground at any one time."
Figuring out how ancient species walked and moved is incredibly difficult—just ask the paleontologists who spent decades misrepresenting Tyrannosaurus rex as an upright, lumbering Godzilla-esque beast. That Garwood and colleagues could pull this from a fossil is awesome, which still does nothing to change the fact that how arachnids walk is super creepy.