Ticks had a taste for dinosaur blood

But it’s not clear which species the bloodsuckers preferred

DINE-O-SAUR In this 99-million-year-old piece of amber, a tick trapped on a dinosaur feather provides rare evidence of the hosts these bloodsuckers preferred during the Cretaceous Period.

E. Peñalver et al/Nature Communications 2017

By Laurel Hamers

December 12, 2017 at 12:00 pm

Ticks once tickled dinosaurs’ feathers.

The tiny arthropods have been surreptitiously sucking blood for more than 100 million years, but evidence of early ticks’ preferred hosts has been scant. Now, samples of amber from Myanmar have caught the critters with their spiny mouthparts inside the cookie jar. A hunk of 99-million-year-old amber holds a tick tangled in a dinosaur feather, researchers report December 12 in Nature Communications. Other pieces of amber suggest that a different tick species from the same period, dubbed Deinocroton draculi, hung out in feathered dinosaur nests (SN: 8/23/14, p. 15).

The tick enmeshed in the feather belongs to the same group of ticks as the deer ticks that bite humans and other animals today. But it’s hard to say what type of dinosaur the tick dined on.

While the researchers say the age of the feather places it on a dinosaur, they can’t tell how birdlike that creature may have been. The feather shares characteristics with the plumage that helps modern birds fly, such as longer barbs on one side of the feather’s shaft than the other. But that shape doesn’t necessarily mean that the feather’s former owner could fly, says study coauthor Ricardo Pérez-de la Fuente, a paleobiologist at the Oxford University Museum of Natural History.

“In the future, we may be able to further narrow down the range of potential hosts, but this is currently the best that can be done with an isolated feather,” adds Ryan McKellar, an invertebrate paleontologist at the Royal Saskatchewan Museum in Regina who wasn’t part of the study.

Another chunk of amber contained two ticks preserved so close together that they were likely entrapped at the same time. Both had what looked like tiny barbed hairs stuck to their bodies — these hairlike structures are frequently found on beetle larvae that hung out in dinosaur nests. “So we think that those beetle hairs were acquired by the ticks in a feathered dinosaur nest,” says Pérez-de la Fuente. That’s further evidence that early ticks fed on dinos, he says.

There’s a “strong case” for that interpretation, McKellar says. “It is impressive to see small clues and associations build up to form a larger picture of ancient ecosystems.”