The Development of Arthropod Segmentation Across the Embryonic/Post-embryonic Divide – An Evolutionary Perspective

Publication Type:Journal Article
Year of Publication:2021
Authors:G. Fusco, Minelli A.
Journal:Frontiers in Ecology and Evolution
Volume:9
Pagination:1-8
Date Published:28/01/2021
ISSN:2296-701X
Keywords:anamorphosis, comparative analysis, development, evolvability, fossils, gene expression, hatching, phylogeny
Abstract:

In many arthropods, the appearance of new segments and their differentiation are not completed by the end of embryogenesis but continue, in different form and degree, well after hatching, in some cases up to the last post-embryonic molt. Focusing on the segmentation process currently described as post-embryonic segment addition (or, anamorphosis), we revise here the current knowledge and discuss it in an evolutionary framework which involves data from fossils, comparative morphology of extant taxa and gene expression. We advise that for a better understanding of the developmental changes underlying the evolution of arthropod segmentation, some key concepts should be applied in a critical way. These include the notion of the segment as a body block and the idea that hatching represents a well-defined divide, shared by all arthropods, between two contrasting developmental phases, embryonic vs. post-embryonic. This eventually reveals the complexity of the developmental processes occurring across hatching, which can evolve in different directions and with a different pace, creating the observed vagueness of the embryonic/post-embryonic divide.

URL:https://www.frontiersin.org/articles/10.3389/fevo.2021.622482/full
DOI:10.3389/fevo.2021.622482
Short Title:Front. Ecol. Evol.
Citation Key:974
Refereed Designation:Refereed
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith