MACROEVOLUTION OF CAMBRIAN ARTHROPOD RESPIRATORY STRUCTURES

Arthropods represent the most diverse and abundant organisms that originated during the Cambrian Explosion, and quickly radiated into disparate body plans. Although much work has been focused on understanding the diversity and morphology of Cambrian arthropods, particularly their affinities and head organization, much less emphasis has been put on the macroevolution of their respiratory organs, particularly the exopodites. This represents a major gap in our understanding of Cambrian arthropod paleobiology and paleoecology, particularly since many sites with exceptional preservation capture intricate details that show significant variability in terms of exopodite complexity, size and structure. In this study we produce the first steps towards a comprehensive quantitative comparison to assess the relationship between the surface of exopodites relative to body size in Cambrian arthropods. This work allows us to detect for the first time patterns of exopod variation across disparate arthropod groups and make inferences about their ecological and physiological significance