Major ontogenetic transitions during Volvox (Chlorophyta) evolution: when and where might they have occurred?

• Published in: Development Genes and Evolution Vol. 226; no. 5; pp. 349 - 354
• Main Author: Desnitskiy, Alexey G.
• Format: Journal Article Book Review
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.09.2016; Springer Nature B.V
• Subjects: Animal Genetics and Genomics; Biological Evolution; Biomedical and Life Sciences; Cell Biology; Chlorophyta; Developmental Biology; Ecology; Evolutionary Biology; Life Cycle Stages; Life Sciences; Photoperiod; Plant Genetics and Genomics; Review; Volvox; Volvox - classification; Volvox - cytology; Volvox - genetics; Volvox - growth & development; Volvox aureus; Volvox carteri; Volvox globator; Volvox spermatosphaera; Volvox tertius; Zoology; Reproductive cell division; Light/dark control; Eco-evo-devo; Gondwana; Ontogenetic diversity; Volvox
• ISSN: 0949-944X; 1432-041X
• DOI: 10.1007/s00427-016-0557-0

This paper represents an attempt to unify data from various lines of Volvox research: developmental biology, biogeography, and evolution. Several species (such as Volvox carteri and Volvox spermatosphaera ) are characterized by rapid divisions of asexual reproductive cells, which may proceed in darkness. By contrast, several other species (such as Volvox aureus , Volvox globator , and Volvox tertius ) exhibit slow and light/dependent divisions. The transition from the former pattern of asexual life cycle to the latter one has occurred in three lineages of the genus Volvox . Since V. aureus (unlike V. carteri ) is able to complete the life cycle at a short photoperiod (8 h light/16 h dark regime), it is reasonable to suggest that the abovementioned evolutionary transitions might have occurred as adaptations to short winter days in high latitudes under warm climate conditions in the deep past. In the case of the lineage leading to V. tertius + Volvox dissipatrix , the crucial reorganizations of asexual life cycle might have occurred between about 45 and 60 million years ago in relatively high latitudes of Southern Hemisphere.