Fossils: Dinosaurs were ticked off by parasites

Ticks were pests for feathered dinosaurs nearly 100 million years ago according to evidence presented in Nature Communications this week. Ticks are currently among the most prevalent blood-feeding parasites, but little had been known about their ancient hosts.

Previous research has shown that ticks were present 99 million years ago, during the Cretaceous period, but fossils of these creatures from this time are rare, and details of their feeding habits and hosts during this period have been unclear. New evidence from 99 million-year-old Cretaceous amber from Myanmar indicates that ticks fed on the blood of feathered dinosaurs, Ricardo Perez-de la Fuente and colleagues report. Within multiple specimens of amber, the authors find ticks, including one that is entangled with a dinosaur feather. Another tick was found to be blood engorged and two others were found in association with material related to a theropod dinosaur nest.

These findings shed light on early tick evolution and ecology, and provide insights into the parasitic relationship between ticks and ancient relatives of birds, which persists today for modern birds.