Ann Arbor Times

A fossil initially misidentified during the Civil War has been correctly identified by a University of Michigan researcher, revealing significant evolutionary insights. Richard J. Knecht, a postdoctoral fellow at the university, discovered that the specimen is not a seaworm as previously thought but an invertebrate known as a lobopod. These creatures are considered ancestors to all arthropods.

Knecht's study suggests that this particular lobopod, named Palaeocampa anthrax, likely lived in freshwater and had chemical defenses indicating it may have spent time on land. This discovery marks the first evidence of this group leaving marine environments.

“This is the first evidence that we have that this group actually did leave the ocean,” Knecht stated. He emphasized the importance of revisiting fossil collections with updated techniques to uncover new insights.

The specimen was originally found among millipedes at Harvard University's Museum of Comparative Zoology and had been misidentified multiple times over its history. “When the specimen was first discovered, lobopods didn’t even exist as a group,” Knecht noted.

Knecht collaborated with Nanfang Yu from Columbia University to analyze chemical residues on the fossil using FTIR spectroscopy. The findings suggest Palaeocampa anthrax might have been amphibious due to its unique spine structure.

The rarity of lobopodians in the fossil record makes this find significant, especially since they are typically preserved under rare geological conditions known as Lagerstätten sites like Mazon Creek in Illinois and Montceau-les-Mines in France.

This discovery provides valuable insight into evolutionary transitions and highlights how older specimens can lead to groundbreaking discoveries when examined with fresh perspectives and advanced technology.

###