I have expectations for what snails look like, and those include curled, smooth shells like I find on the critters in my garden. A study on a new species of snail discovered in 99-million-year-old Burmese amber has expanded my world view of land snails to include hairy shells.
The snail specimen in question is named Archaeocyclotus brevivillosus and it's just over 1 inch (26.5 millimeters) long with short bristle-like hairs on its shell. The fossilized tree resin preserved the snail, giving scientists a window into the animal's ancient world.
An international team of researchers published a paper on the snail for the December issue of the journal Cretaceous Research.
This might be the first time I've heard of a hairy snail, but scientists have been in the know. "This is already the sixth species of hairy-shelled Cyclophoridae, a group of tropical land nails, found so far embedded in Mesozoic amber," said Adrienne Jochum in a Senckenberg Research Institute statement on Tuesday.
The fossil snail's discovery feeds into some lingering questions about hair on snail shells. Some modern snails also sport hairs, and hairs have popped up in diverse, distantly related species. What is the purpose? It seems likely hair gave the fossil snail some sort of evolutionary advantage.
Jochum offered several ideas for the usefulness of the hairs. They might have helped the snails hang onto plants better or may have allowed them to regulate their temperature by gathering water droplets. Other possible uses could have been as camouflage or protection from predators. "And finally, it cannot be ruled out that the hairs provided an advantage in sexual selection," Jochum said.
Sticky resin oozes from trees and solidifies around unlucky fauna or flora, freezing them in time and helping to build a picture of what life was like so long ago. The snail is just the latest in a line of fascinating amber discoveries, includingand a .
The purpose of shell hairs may still be under investigation, but this sure makes the lives of ancient snails sound exciting.