Our only direct information on the origin of vertebrates comes from preserved soft-bodied Cambrian chordates; however, reading this fossil record is fraught with difficulties owing to a lack of data on when and how important characters change as they decompose. Here, from experimental decay of amphioxus and ammocoetes, it is shown that loss of chordate characters during decay is non-random, with the features that are most phylogenetically informative tending to decay first.
- Robert S. Sansom
- Sarah E. Gabbott
- Mark A. Purnell