Artículo de revista
Thorson's rule, life-history evolution, and diversification of benthic octopuses (Cephalopoda: Octopodoidea)
Fecha
2018Registro en:
Evolution 72-9: 1829–1839
15585646
00143820
10.1111/evo.13559
Autor
Ibáñez, Christian M.
Rezende, Enrico
Sepúlveda, Roger D.
Avaria Llautureo, Jorge
Hernández, Cristián E.
Sellanes, Javier
Poulin, Elie
Pardo Gandarillas, María Cecilia
Institución
Resumen
Here, we evaluate the so-called Thorson’s rule, which posits that direct-development and larger eggs are favored toward the poles in marine organisms and whose validity been the subject of considerable debate in the literature, combining an expanded phenotypic dataset encompassing 60 species of benthic octopuses with a new molecular phylogeny. Phylogenetic reconstruction shows two
clades: clade 1 including species of the families Eledonidae, Megaleledonidae, Bathypolypodidae, and Enteroctopodidae, and clade 2 including species of Octopodidae. Egg size, development mode, and all environmental variables exhibited phylogenetic signal, partly due to differences between the two clades: whereas most species in clade 1 inhabit cold and deep waters, exhibit large eggs and hatchling with holobenthic development, species from clade 2 inhabit tropical-temperate and shallow waters, evolved small eggs, and generally exhibit merobenthic development. Phylogenetic regressions show that egg size exhibits a conspicuous
latitudinal cline, and that both egg size and development mode vary with water temperature. Additionally, analyses suggest that
egg size is constrained by body size in lineages with holobenthic development. Taken together, results suggest that the variation in egg size and development mode across benthic octopuses is adaptive and associated with water temperature, supporting Thorson’s rule in these organisms