The role of phylogeny in morphological and developmental studies of animal domestication

GEIGER M.; FLORES D.; SÁNCHEZ-VILLAGRA M.R.; HECK L.; SEGURA V.; VEITSCHEGGER K.

Gothenburg

Congreso; BioSyst.EU; 2017

Federation of European Biological Systematic Societies

Current studies of domestication concentrate on genomics and zooarcheologicalapproaches. Investigation of phylogenetically - informeddevelopmental morphology can also provide major insights into evolution, asinformed by studies of breeds of domesticated forms and comparisons with wildcounterparts. Features of the ?domestication syndrome?, a hypothetical set toappear in domesticated forms, do not appear universally across mammalianspecies, only pigmentation and rostral shortening do. Likewise, ontogenetictrajectories are not equally modified in domesticated forms of all species. Theexamination of more than 400 skulls across 13 domesticated forms and their wildcounterparts serve to quantify and analyse the changes with multivariatestatistics in 14 skull and mandibular variables. There are significantdifferences in growth allometry across the 13 species -affectingtheir evolvability -the amount of morphological diversity or disparity that can be attainedthrough selective breeding, which we quantifiy for some of the speciesinvestigate (dogs, cattle, and horses). Wolves-dogs andllamas-guanacos are the pairs that exhibit the greatest amount of changebetween the wild and the domestic form, domestic-wild pigsexhibit the least amount of differences. In spite of the statisticaldifferences in the growth trajectory, there is little in the amount of changein Equus, Ovis, Camelus and Sus. The wild rabbit is characterised by a highproportion of allometric growth, making it a species with high potential fordisparity. Skull variables showing the least amount of change are in theneurocranium (e.g., breadth of the braincase). The length of the nasals (LN) isthe variable showing the greatest amount of change when all species areconsidered in the comparison between the wild and the domestic forms. Ongoingwork on rates of evolution shows that these rates are lower in the process ofdomestication when compared to strong selection for particular breed traits.The differential patterns of change across species during domestication, alsoshown in life history traits (e.g., degree of variation in gestation length)show that using the silver fox experiment or the dog as models of domesticationis of limited value, as canids exhibit within carnivorans and across mammals ingeneral, a rather singular pattern in the changes associated withdomestication.