The fossilized digestive system of the trilobite Palaeolenus lantenoisi, complete with the stomach structure called a crop (oval region at the top), digestive glands (left and right), and central canal (center), dating back to the early Cambrian period 500 million years ago.© F. CHEN See M.J. Hopkins et al., “The oldest known digestive system consisting of both paired digestive glands and a crop from exceptionally preserved trilobites of the Guanshan Biota (Early Cambrian, China),” PLOS ONE, doi:10.1371/journal.pone.0184982, 2017.

Interested in reading more?

The Scientist ARCHIVES

Become a Member of

Receive full access to more than 35 years of archives, as well as TS Digest, digital editions of The Scientist, feature stories, and much more!
Already a member?