Integrative taxonomy Gustav Paulay Florida Museum of Natural History University of Florida

Integrative taxonomy Use of multiple lines of evidence Field - museum - lab Ecology - behavior - morphology - genetics - geography Distinguishing between morphs and species Two or more independent characters showing distinction between species

Integrative taxonomy: Actinopyga mauritiana - guamensis

Not seeing species where there are cukes vs. primates –different foci for sensory perception unequal rates of evolution –phenotype: morphology, behavior, color pattern... –genotype: sequence divergence –reproductive isolation

Supposed distribution of Scutellastra flexuosa and exusta Powell, 1968

but what is really going on... NJ K2P COI

Seeing species where there aren’t ecophenotypic variation ontogenetic variation geographic variation ecological variation - depth, habitat, etc polymorphism paralogous loci former divergence now united

Paralogous loci: mitochondrial genes gone nuclear in Alpheus Williams & Knowlton 2001 Mol Biol Evol

Cypraea tigris a species differentiated, then united

ESU - reciprocal monophyly DNA - gene flow - BSC reciprocal monophyly implies lack of recent genetic connections need several samples of each form to test reliability of conclusion depends on depth of intra- vs. inter-specific variation in sympatry - separate biological species in allopatry - separate ESUs, species status subjective

Basinal/subbasinal speciation common perceived as other dominant mode of speciation by past studies predominant mode in Cypraeidae, Aspidochirotida, Diogenidae, Parribacus Cypraea punctata complex

Where are the species limits?

Lack of reciprocal monophyly morphs rather than species distinct species, but: –introgression –insufficient time for sorting deep coalescent rapid speciation

Introgression in Astralium

Introgression in Bohadschia argus? Unusual form only in W Pacific; never seen in Polynesia, etc. Need compare independent markers to test

Insufficient time for sorting Gene trees vs. species trees: coalescence theory Avise 1999 Phylogeography

Evolution of reproductive isolation Slow –most gastropod –deep divergence among allopatric ESUs –clear reciprocal monophyly –slow to secondary sympatry / biological species Rapid –echinoids, holothuroids –shallow divergence among sympatric species –potential paraphyletic species –rapid to secondary sympatry / biological species

1.Two deeply divergent clades: A & B sympatric on 8 island groups 2.30 ESUs so far 3.Pigmentation separates major and minor clades. Astralium rhodostomum complex

Geographic signal no signal 94% divergences < 10 Ma retain signal (115 of 122) Persistence of allopatry - Cypraeidae 94% divergences < 10 Ma retain allopatry (115 of 122)

Echinometra mathaei complex Rapid secondary sympatry Facilitated by rapid evolution of fertilization proteins? ~1 Ma COI Bindin Landry et al Proc Roy Soc COI Bindin

Cukes like urchins: Actinopyga obesa complex

Stichopus variegatus complex

Advantages of sequence data Directly test genetic connections Very large number of characters Independent markers - independent sources “Independent” of morphology - so can trace evolution of form, etc on gene tree without circularity

Potential problems with sequence data depth of coalescent vs. interspecific divergence paralogous sequences introgression –selective sweeps –homogenization through drift