Ancient Tapeworm Eggs Found in Fossilized Shark Poop
Charles Choi, LiveScience Contributor
Date: 30 January 2013 Time: 05:19 PM ET
Ancient tapeworm eggs found in 270-million-year-old shark poop suggests these parasites may have plagued animals for much longer than previously known, researchers say.
Tapeworms cling to the inner walls of the intestines of vertebrates — creatures with backbones such as fish, pigs, cows and humans. When these parasites reach adulthood, they unleash their eggs on the world via the feces of their hosts.
Investigating the early history of such parasites of vertebrates is tricky because fossils of these parasites dating back to the age of dinosaurs or before are rare. One way researchers might unearth such fossils is by analyzing coprolites, or fossilized dung.
Scientists now reveal they found a spiral-shaped coprolite from a shark that holds a cluster of 93 oval tapeworm eggs. One of them even contains a probable developing larva, which held a cluster of fiberlike objects that may have been the beginnings of hooklets used to attach to a host's intestines as adults ...