LOGIN

RSS Facebook Twitter YouTube
GLOSSARY       

SEARCHGLOSSARY

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

PROFILESEARCH

Evolutionary Origin and Early Biogeography of Otophysan Fishes

Home Forums Ichthyology Evolutionary Origin and Early Biogeography of Otophysan Fishes

This topic contains 0 replies, has 1 voice, and was last updated by  coelacanth 4 years, 8 months ago.

Viewing 3 posts - 1 through 3 (of 3 total)
  • Author
    Posts
  • #302655

    Matt
    Keymaster

    Evolution – accepted article

    Abstract

    Biogeography of the mega-diverse, freshwater and globally-distributed Otophysi has received considerable attention. The attraction largely stems from assumptions as its ancient origin, and by being almost exclusively freshwater, their suitability as to explanations of trans-oceanic distributions. Despite multiple hypotheses explaining present-day distributions, problems remain, precluding more parsimonious explanations. Underlying previous hypotheses involve alternative phylogenies for Otophysi, uncertainties as to temporal diversification and assumptions integral to various explanations. We reexamine the origin and early diversification of this clade based on a comprehensive time-calibrated, molecular-based phylogenetic analysis and event-based approaches for ancestral range inference of lineages. Our results do not corroborate current phylogenetic classifications of otophysans. We demonstrate Siluriformes are never sister to Gymnotiformes and Characiformes are most likely non-monophyletic. Divergence-time estimates specify a split between Cypriniformes and Characiphysi as a result of fragmentation of Pangea. The early diversification of characiphysans either predated, or was contemporary with, the separation of Africa and South America, and involved a combination of within- and between-continental divergence events for these lineages. The inter-continental diversification of siluroids and characoids postdated major inter-continental tectonic fragmentations (<90Mya). Post-tectonic drift dispersals are hypothesized to account for current patterns of distribution of these latter two clades.

    #350432

    Stefan
    Member

    Interesting! Do you have access Matt?

    #350451

    coelacanth
    Participant

    Tin hat time for the authors I reckon! 

    @matt said:
    The early diversification of characiphysans either predated, or was contemporary with, the separation of Africa and South America, and involved a combination of within- and between-continental divergence events for these lineages. The inter-continental diversification of siluroids and characoids postdated major inter-continental tectonic fragmentations (<90Mya). Post-tectonic drift dispersals are hypothesized to account for current patterns of distribution of these latter two clades.

    I thought this was already the most widely-accepted hypothesis?

Viewing 3 posts - 1 through 3 (of 3 total)

You must be logged in to reply to this topic.