Brachiopods are small invertebrates that live on the seafloor and are prominent in the fossil record from 540 to 250 million years ago. An interesting feature of some species is that large spines develop on their exterior surfaces. These spines are thought to have evolved for defense against predators, but fossils are limited in how much information they contain about how organisms interact with each other. In this study, I examined wound markings on fossils of both a spiny (Atrypa rockfordensis) and spineless (Atrypa devoniana) species of brachiopod. Results show that spiny brachiopods were less frequently injured, suggesting that spines were an efficient defense against predators. Furthermore, spineless brachiopods experienced predation at all sizes whereas spiny brachiopods only experienced predation at smaller sizes. These findings are useful in understanding how organisms interacted with each other in prehistoric times and further research can help us more accurately reconstruct ancient marine ecosystems from around the world.
Kokesh, Broc S.
"The Influence of Spines and Size Refuge on Predation of Devonian Brachiopods from the Lime Creek Formation near Rockford, Iowa,"
Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal: Vol. 2
, Article 4.
Available at: http://digitalcommons.morris.umn.edu/horizons/vol2/iss1/4