<< the fastest rates of speciation occur in species-poor regions outside the tropics, and that high-latitude fish lineages form new species at much faster rates than their tropical counterparts. High rates of speciation occur in geographical regions that are characterized by low surface temperatures and high endemism. >>
AA << results reject a broad class of mechanisms under which the tropics serve as an evolutionary cradle for marine fish diversity and raise new questions about why the coldest oceans on Earth are present-day hotspots of species formation. >>
https://www.nature.com/articles/s41586-018-0273-1
Daniel L. Rabosky, Jonathan Chang, et al. An inverse latitudinal gradient in speciation rate for marine fishes.
Nature. July 4, 2018. doi: 10.1038/s41586-018-0273-1
<< Our results are counterintuitive and unexpected, because we find that speciation is actually fastest in the geographic regions with the lowest species richness. (..) Extinction is the missing piece of this puzzle >> Daniel Rabosky
Frigid polar oceans, not balmy coral reefs, are species-formation hot spots. University of Michigan. July 4, 2018.
https://m.phys.org/news/2018-07-frigid-polar-oceans-balmy-coral.html
also
# s-evol: early life in cold ocean. March 20, 2016.
https://flashontrack.blogspot.com/2016/03/s-evol-early-life-in-cold-ocean.html