As you might imagine, being infected with a tapeworm isn't very pleasant. For the creationist, then, we wonder when these tapeworms came to be? Were they always parasitic like this? Were they created during creation week? Or at the Fall? Were there tapeworms on the Ark? Were some of the animals or maybe even Noah himself infected?
I don't think we can answer most of those questions right now, but this new shark paper can help us put a minimum age on the origin of tapeworms. The shark coprolites described in the paper are from the Middle to Upper Permian, which by pretty much any creationist's estimate would be a Flood deposit. That means that the shark coprolite fossilized in this Flood deposit must have been produced before or during the Flood. So the presence of tapeworm eggs in this coprolite produced before or during the Flood must have come from a tapeworm occupying a shark intestine before or during the Flood.
Does this mean that the shark was infected with some kind of disease caused by the tapeworm? We don't know. All we know is that the shark had tapeworms living in its intestine. Since modern tapeworms produce unpleasant symptoms, we might assume that this pre-Flood tapeworm did too.
All in all, an interesting paper, and it's free to read.
Dentzien-Dias et al. 2013. Tapeworm eggs in a 270 million-year-old shark coprolite. PLoS One 8(1): e55007.
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