Image: Wang Cheng, courtesy of Oregon State University
-
Why Is the Penis Shaped Like That?
Why do testicles hang the way they do? Is there an adaptive function to the female orgasm? What does it feel like to want to kill yourself? Does “free will”...
Read More »
Paleo-pests about 10 times bigger than today's fleas may have sneaked up on a huge dinosaur, crawled onto its soft underbelly and taken a bite, likely a painful one, say researchers who have discovered fossils of the flealike organisms.
"It would have felt about like a hypodermic needle going in, a flea shot, if not a flu shot," George Poinar Jr., a professor emeritus of zoology at Oregon State University, said in a statement. "We can be thankful our modern fleas are not nearly this big," said Poinar, who wrote a commentary alongside the research article published online April 24 in the journal Current Biology.
One possible lifesaver for dinosaurs: These bloodsuckers couldn't jump like today's pesky fleas. Even so, past research suggests dinosaurs may have also been the first beasts tormented by lice.
The fossils of the two newly identified "flea" species, now called Pseudopulex jurassicus and Pseudopulex magnus, were discovered in Inner Mongolia. These "compression fossils," rather than impressions, are the actual preserved insects that fossilized over millions of years. [See Photos of the Dinosaur Fleas]
"These fossils have excellent preservation of detailed insect body structures, as if nature took a high-resolution photo of these creatures 165 million years ago," said Chungkun Shih, a visiting professor working with co-author Dong Ren at the Capital Normal University in Beijing.
Details of paleo-pests
The insects would have had flat bodies like a bedbug or tick, and claws long enough to reach over the scales covering a dinosaur so they could hold on while sucking its blood.
Modern fleas are more laterally compressed and have shorter antennae, features that allow them to move quickly through the fur or feathers of their hosts.
The smaller of the new species, living some 165 million years ago, P. jurassicus would have been about 0.7 inches (17 millimeters) in length, not including its antennae, with mouthparts extending some 0.13 (3.4 mm), or more than twice the length of the head.
The monster of the duo, P. magnus, which lived about 125 million years ago, was even bigger, with a body length of 0.9 inches (22.8 mm) and mouthparts reaching nearly 0.20 inches (5.2 mm) in length.
This large body size as well as the long, serrated mouthparts "for piercing tough and thick skin or hides of hosts suggest that these primitive ectoparasites might have lived on and sucked the blood of relatively large hosts, such as contemporaneous feathered dinosaurs and/or pterosaurs or medium-sized mammals, found in the Early Cretaceous, but not the Middle Jurassic," Shih wrote in an email to LiveScience.
To find out which dinosaurs may have needed flea collars, the team surveyed information on coexisting animals that lived at the same time and place as these insects. During the middle Jurassic, potential feathered-dinosaur hosts may have been Pedopenna daohugouensis and Epidexipteryx hui. During the early Cretaceous, when P. magnus lived, Sinosauropteryx prima and Microraptor gui may have served as hosts, Shih noted.
More dino fleas?
The two fossil insects seem to resemble "dinosaur fleas" reported in the journal Nature last month by Diying Huang, at the Chinese Academy of Sciences, and colleagues.
See what we're tweeting about
3 Comments
Add CommentThere were many types of dinosaurs - some may have been thin skinned like birds and others (Sauropods) must have been very thick skinned just to keep from splitting open. Do rhinoceroses have fleas or lice? I imagine that at least most of Sauropods' skin might have required a diamond-tipped drill to achieve penetration...
Reply | Report Abuse | Link to thisDoes anyone else remember the sardonic SF short story about the time-travelling hunter seeking new trophies who fells a large dino only to be jumped by its departing parasites and "lovingly picked clean". Keep looking over those fossils, you may find him ...
Reply | Report Abuse | Link to thisTo answer my own question, I happened to have a TV program "Wild India" turned on tonight when they mentioned that rhinoceroses liked to roll around in the mud to 'soothe their sensitive skin' and protect against parasites.
Reply | Report Abuse | Link to thisSo, did Sauropods roll around in the mud, too?
That would have been a sight!