Still full of its last meal (Image: Y. Yao et al., Current Biology)

Bloodsucking bugs may have been around for a lot longer than we thought. Newly discovered fossils show that bugs have been feeding on blood since the height of the dinosaur era. One of the fossilised bugs found seems to have died just after feasting on blood.

Dong Ren of Capital Normal University in Beijing and his colleagues studied three fossilised bugs from China’s fossil-rich Yixian Formation. They realised that the insects belonged to a hitherto-unknown family of true bugs that lived in the early Cretaceous period, around 130 million years ago.

Chemical analysis showed that the three bug fossils contained a lot of iron, suggesting they drank blood. It’s unclear if they fed on dinosaurs, or other large animals.


Previously, the oldest-known blood-feeding bug was from 100 million years ago. The new fossils push the record back 30 million years.

Blood feeding has evolved independently at least twice amongst true bugs. Such insects can carry diseases from host to host, harming animals that may be hundreds of times their size. Ren says it’s not clear what, if any, diseases the Cretaceous bugs might have carried.

Feeding on blood offered the insects a high-quality, protein-rich diet, says Gordon Hamilton of Keele University in the UK.

Other insects like midges probably evolved blood-feeding before bugs, says David Grimaldi of the American Museum of Natural History in New York. There are fossils of seemingly bloodsucking midges from as much as 230 million years ago.

Journal reference: Current Biology, DOI: 10.1016/j.cub.2014.06.045

Since this article was first published on 25 July 2014, the distinction between earliest bloodsucking bugs and insects has been clarified.