Evolution of trilobite enrolment during the Great Ordovician Biodiversification Event: insights from kinematic modelling

• DOI: 10.1111/let.12242
• Publication Date: 2017-09-21T05:38:36Z
• Authors: Jorge Esteve; Juan Carlos Gutié...; Pedro Rubio; Isabel Rábano
• Keywords: functional morphology; Functional morphology; arthropods; Spain Palaeozoic Phacopids; 01 natural sciences; Palaeozoic; phacopids; Spain; Biomechanics; Arthropods; 0105 earth and related environmental sciences

The Great Ordovician Biodiversification Event (GOBE) represents a diversification at lower taxonomic levels of most body plans that had appeared during the Cambrian explosion. Among trilobites, several novelties related to enrolment evolved during the GOBE. A kinematic analysis by means of 3D modelling of some new enrolment types shows no relationship with those of the Cambrian trilobites. While some structures emerged for the first time in Ordovician trilobites (e.g. articulations and panderian organs), other structures (e.g. anterior and posterior arch in head and tail) appear earlier in Cambrian trilobites. Our results suggest that the evolution of some groups was clearly rooted in the Cambrian explosion while others clearly appeared during the GOBE. This work is a contribution to the IGCP project 653 ‘The Onset of the Great Ordovician Biodiversification Event (GOBE)’ and an outcome of the projects CGL2012‐39471/BTE and CGL2013‐48877‐P of the Spanish Ministry of Economy, Industry and Competitiveness. J.E. was funded by a Juan de la Cierva Grant (FPDI‐2013‐17337). Peer reviewed