[ad_1]
Paleontologists have described the first three-dimensional conservation of soft tissue And calathus hermanastes, a skeletal metazoan (multicellular animal) that lived 547 million years ago (Ediacaran period) in what is now Namibia, and established a strong evolutionary link between the Ediacaran and Early Cambrian metazoa.
Namacalathus (numbered individuals). Centimeter scale. Image Credit: Shore et al., doi: 10.1126 / sciadv.abf2933.
Until recently, little was known about the origins of the animals that evolved during the Cambrian Explosion due to a lack of well-preserved fossil evidence.
The mysterious origins of the animals that evolved during this time baffled 19th-century naturalist Charles Darwin. It is often called Darwin’s dilemma.
Prior to the new study, it had proven difficult to trace connections to previous animals because their soft tissues – which provide vital clues to the animals’ ancestry – almost always break down over time.
During fieldwork in Namibia, Professor Rachel Wood of the University of Edinburgh and her colleagues unearthed the well-preserved fossilized remains of And calathus hermanastes.
Using an X-ray imaging technique, they found some of the soft tissue of animals perfectly preserved inside the fossils by a metallic mineral called pyrite.
Until now, paleontologists had identified only skeletal remains of And calathus hermanastes.
Reconstruction of the living Namacalathus: 1 – rod; 2 – parental cut; 3 – girls cups; 4 – hollow ciliated tentacles; 5 – thorns; 6 – side light; 7 – central opening; 8 – internal skeletal layer, laminated with columnar microlamellar inflections; 9 – internal (medium) skeleton later, rich in organic matter; 10 – Outer outer skeletal layer, foliate with columnar skeletal inflections. Image credit: J. Sibbick.
Professor Wood and his co-authors then examined the soft tissue of the ediacarid animal and compared it to that of animals that evolved later.
They found that And calathus hermanastes was one of the earliest ancestors of the species that appeared during the Cambrian Explosion. Among them are prehistoric types of worms and mollusks.
“These are exceptional fossils, which give us insight into the biological affinity of some of the oldest animals,” said Professor Wood.
“They help us trace the roots of the Cambrian explosion and the origin of modern animal groups.”
“Such preservation opens up many new avenues for research into the history of life, which was not possible before.”
The study was published in the journal Scientific advances.
_____
AJ Shore et al. 2021. Ediacaran metazoan reveals affinity for lophotrochozoan and deepens root of Cambrian explosion. Scientific advances 7 (1): eabf2933; doi: 10.1126 / sciadv.abf2933
[ad_2]
Source link