Enduring evolutionary embellishment of cloudinids in the Cambrian

Area of Science:

• Paleontology
• Evolutionary Biology
• Animal Evolution

Background:

• The Ediacaran-Cambrian transition and Cambrian Explosion are pivotal in animal evolution.
• Phylogenetic linkages and trait evolution are crucial for understanding this period.
• Sparse fossil records and morphological simplicity pose challenges in tracing early animal lineages.

Purpose of the Study:

• To establish phylogenetic links between Ediacaran cloudinids and Cambrian animals.
• To monitor trait evolution within an animal lineage across the Ediacaran-Cambrian boundary.
• To present the first evidence of an Ediacaran animal lineage successfully diversifying through the Cambrian Explosion.

Main Methods:

• Identifying derived characters in cloudinids and Cambrian animals.
• Comparing cloudinid morphology, including dichotomous branching, with cnidarian reproduction.
• Tracking morphological changes from the Late Ediacaran to the Miaolingian.

Main Results:

• Derived characters link Late Ediacaran cloudinids to Cambrian animals with cnidarian affinity.
• Cloudinids represent an animal lineage present in the Ediacaran that diversified during the Cambrian Explosion.
• Dichotomous branching in cloudinids shows similarities to cnidarian asexual reproduction.

Conclusions:

• Cloudinids successfully endured and diversified through the Cambrian Explosion, enhancing robustness and complexity.
• Morphological changes in cloudinids offer insights into early animal group responses to the Cambrian Explosion.
• This study provides a unique glimpse into the evolutionary trajectory of a primeval animal group.