Ancient Fish Boasted Great Abs

For the first time, researchers have conducted an analysis of the musculature of a 380 million-year-old armored fish, which has led to a surprising discovery: the fish boasted strong abs.

While the word “fossil” may conjure up a vision of rocks and skeletons, soft tissues are occasionally uncovered, serving as a rare and valuable window to the biology of extinct organisms.

Such was the case when, a few years ago, an Australian team of researchers made the remarkable discovery that a group of fossils discovered in the Gogo Formation, a sedimentary rock formation in the northwestern region of the country, included soft tissue containing nerve and muscle cells.

Collaborating with a research group from Uppsala University, and with the European Synchrotron (ESRF) in Grenoble, France, the scientists successfully documented and reconstructed the musculature of the placoderms, an extinct group featuring some of the earliest jawed fish.

“High contrast X-ray images were produced thanks to a powerful beam and a protocol developed for fossil imaging at the ESRF,” Sophie Sanchez, one of the authors, said in a press release. “This is unique in the world and has enabled us to ‘reconstruct’ some fossilized muscles and document the muscles of neck and abdomen in these early jawed fish without damaging or affecting the fossilized remains.”

Doing so, the scientists said, will aid in developing a better understanding regarding the evolution of such muscles during the important transition from jawless to jawed vertebrates.

“This shows that vertebrates developed sophisticated musculature much earlier than we had thought,” explained Per Ahlberg, co-author of the project. “It also cautions against thinking that we can interpret fossil organisms simply by metaphorically draping their skeleton in the soft tissues of living relatives.”

Other researchers came from Curtin University in Perth, Australia, as well as the Western Australian Museum, Flinders University, the Research School of Earth Sciences at Australian National University, the Research School of Physics and Engineering at the Australian National University and the Australian Regenerative Medicine Institute.