Namacalathus (individuals numbered). Centimeter scale. Image credit: Shore et al., doi: 10.1126/sciadv.abf2933.
SciNews has a story about a fossil that links the animals of the Ediacaran and the Cambrian periods. The fossils, which date to about 547 million years ago, were found by University of Edinburgh’s Professor Rachel Wood as she did field work in Namibia, in Africa. The fossil preserves soft tissue from an animal called Namacalathus hermanastes. The research was published in the journal Science Advances.
Until recently, little was known about the origins of animals that evolved during the Cambrian explosion event because of a lack of well-preserved fossil evidence.
The mysterious origins of animals that evolved at this time baffled 19th century naturalist Charles Darwin. It is often referred to as Darwin’s dilemma.
Prior to the new study, it had proven difficult to trace links with earlier animals because their soft tissues — which provide vital clues about the animals’ ancestry — almost always break down over time.
During fieldwork in Namibia, University of Edinburgh’s Professor Rachel Wood and colleagues unearthed the well-preserved fossilized remains of Namacalathus hermanastes.
Using an X-ray imaging technique, they found some of the animals’ soft tissues immaculately preserved inside the fossils by a metallic mineral called pyrite.
Until now, paleontologists had only ever identified skeletal remains of Namacalathus hermanastes.
Reconstruction of the living Namacalathus: 1 – stem; 2 – parental cup; 3 – daughter cups; 4 – hollow ciliated tentacles; 5 – spines; 6 – lateral lumen; 7 – central opening; 8 – inner skeletal layer, foliated with columnar microlamellar inflections; 9 – internal (middle) skeletal later, organic rich; 10 – external outer skeletal layer, foliated with columnar skeletal inflections. Image credit: J. Sibbick.
