Miniaturization during a Silurian environmental crisis generated the modern brittle star body plan.
Commun Biol
; 5(1): 14, 2022 01 10.
Article
em En
| MEDLINE
| ID: mdl-35013524
ABSTRACT
Pivotal anatomical innovations often seem to appear by chance when viewed through the lens of the fossil record. As a consequence, specific driving forces behind the origination of major organismal clades generally remain speculative. Here, we present a rare exception to this axiom by constraining the appearance of a diverse animal group (the living Ophiuroidea) to a single speciation event rather than hypothetical ancestors. Fossils belonging to a new pair of temporally consecutive species of brittle stars (Ophiopetagno paicei gen. et sp. nov. and Muldaster haakei gen. et sp. nov.) from the Silurian (444-419 Mya) of Sweden reveal a process of miniaturization that temporally coincides with a global extinction and environmental perturbation known as the Mulde Event. The reduction in size from O. paicei to M. haakei forced a structural simplification of the ophiuroid skeleton through ontogenetic retention of juvenile traits, thereby generating the modern brittle star bauplan.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Equinodermos
/
Meio Ambiente
/
Evolução Biológica
/
Fósseis
Limite:
Animals
País/Região como assunto:
Europa
Idioma:
En
Ano de publicação:
2022
Tipo de documento:
Article