Blood Found in Mosquito Fossil: “One of a Kind”

We officially have fossil evidence that the whining bane of many a summer night was busy sucking blood as far back as 46 million years ago, a new study says.

Scientists have discovered blood in a mosquito fossil in the oil shale of northwestern Montana.

Researchers found the insect’s last blood meal by detecting hemea pigment in red blood cells—via a special method of nondestructive x-ray spectrometry.

Photo of the fossil of a blood-engorged mosquito.
A closeup of the blood-sucking mosquito. Photograph courtesy Smithsonian Institution

It’s a major discovery because it demonstrates that “large complex organic molecules do indeed survive over deep time,” said Dale Greenwalt, a volunteer research collaborator at the Smithsonian Institution’s National Museum of Natural History and lead author of the new study.

The Earth was a very different place 46 million years ago, in what’s known as the Eocene epoch. A warm, balmy climate reigned, with palm trees growing as far north as modern-day Alaska. After the demise of the dinosaurs, lizards, megafauna, and early mammals roamed the land. And buzzing incessantly among them was that all-too-familiar pest … the mosquito.

One of a Kind

As for what creature the ancient mosquito may have feasted on before it was frozen in time, researchers can only speculate. (Also see “Here’s What Happens Inside You When a Mosquito Bites.”)

According to Greenwalt, the mosquito may belong to the genus Culiseta, which could provide a clue.

“Some of the species of mosquitoes in the genus Culiseta that live today feed on birds. The climate was subtropical and there existed in the forests that surrounded the lake small primates similar to the tarsiers that live today only in Indonesia,” said Greenwalt, whose study appeared this week in the Proceedings of the National Academy of Sciences.

Bloodsucking (or hematophagy, if you prefer) is a common practice among insects. In fact, from fleas to ticks to mosquitoes, a staggering 14,000 species do it. But in contrast to the Jurassic Park fantasies of perfect dinosaur-blood-filled mosquitoes frozen in amber, finding a specimen that’s survived millions of years intact is a tall order.

According to Greenwalt, “The chance that a blood-engorged mosquito, with a very fragile abdomen blown up like a balloon, could be preserved intact are infinitesimally small; this specimen is one of a kind.”

Pet Velociraptors Unlikely

And while heme was identified in the new specimen, finding DNA is a much trickier proposition. As for a scenario in which viable DNA could be recovered from a fossilized mosquito, a la Jurassic Park, and used to make a new dinosaur, so far it’s never been done. (See “Revisiting My Teenage Crush on Jurassic Park (and Getting the Scoop on the Movie’s Dinos).”)

“DNA is even more fragile, and recent studies have shown that, even after a few thousand years, the DNA is completely degraded,” said Greenwalt.

“Who knows what future technologies might allow? But at the present time, fossil DNA exists only in the movies.”

So those hoping for a pet velociraptor will have to wait.

Follow Stefan Sirucek on Twitter.

Stefan Sirucek is a writer and journalist who reports from both sides of the Atlantic. He's written for the Huffington Post and Wall Street Journal. Follow him on Twitter at @sirstefan.

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