Four ways to become cryptic Jos Cerca Ph
Four ways to become cryptic José Cerca Ph. D student @ Ui. Oslo @cryptic_omics josecercadeoliveira. org José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Brief overview 1. Cryptic species – Introduction, definiton and context (Struck et al. 2017) 2. Four ways to be cryptic (Struck et al. 2017) 3. Implications for Evolutionary Biology, Ecology, Systematics, Paleobiology (Cerca unpublished) José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Despite this interest. . . cryptic species have been typically dismissed as taxonomic artefacts wherein. . . someone had overlooked a character. . . wrong focus on taxonomic traits In the last International Polychaeta Conference I heard from someone “My supervisor once told me there is no such thing as a cryptic species. Only bad taxonomists. ” José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Definition: José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 “Neutral expected divergence” Cryptic species Separate evolutionary lineages which maintain/preserve morphological Hawaiian honeycreepers similarity. José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 We suggest that the occurence of some cryptic species can be biologically explained. We include “ 4 ways to be cryptic”: A. Recent divergence B. Parallelism C. Convergence D. Stasis José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 “In speciation research it is commonly assumed that in the early stages of speciation selection acts largely on physiological, immunological, reproductive, or behavioral traits rather than on morphology” Species A Species B Colonization of a new environment Ancestral species Speciation event Past Present José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018 Physiological ≠ ’s
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 A. Recent divergence B. Parallelism C. Convergence D. Stasis José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 Sea Swift HF et al 2016 MPE Independent colonization events José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 A. Recent divergence B. Parallelism C. Convergence D. Stasis José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 «Convergence: independent evolution of a derived character state between taxa from different ancestral traits. » “Ancestral traits” «Parallelism: independent evolution of a character state in different taxa from a similar and shared ancestral trait. » Struck et al 2018 Convergence Parallelism Swift HF et al 2016 MPE José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Struck, . . . Cerca. . . Dimitrov & Bachmann et al 2017 A. Recent divergence B. Parallelism C. Convergence D. Stasis José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Cerca, Dimitrov, Struck unpublished BEAST divergence dates Maximum Likelihood Bipartitioned Tree 2 mt genes + 2 nuclear ~ 30 MY ~ 200 MY ~ 80 MY José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Cryptic species Cerca, et al unpublished Morphological divergence (SEM, LM measurements) Morphological stasis – Extreme conservation of morphology Next steps: Confirming genetic divergence and the evolutionary history of the species complex using genomic approaches (RADseq) José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Implications of Cryptic Species: Evolutionary Biology Cerca unpublished What causes reproductively isolated genetic lineages to maintain similar morphology through time, independently? Developmental Limitations? Time Limited genetic diversity? Genetic incompabilities? Extrinsic factors: (i. e. biological interactions or environment) José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Implications of Cryptic Species: Evolutionary Biology Cerca unpublished José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Implications of Cryptic Species: Ecology Cerca unpublished Competitive exclusion principle “two species competing for the same limiting resource cannot coexist” While collecting Stygocapitella subterranea we find very divergent clades in the same sand bag – “sympatry” José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Implications of Cryptic Species: Systematics Cerca unpublished How many more species are there out there? Are there biological groups more prone to have cryptic species? José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Implications of Cryptic Species: Paleobiology Provided pronounced divergence times Fossil record (“morphological” species) Cryptic species Speciation Extinction Paleontological Time scale José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018 Cerca unpublished
Take home message 1. Cryptic species can occur due to natural phenomena: A. Recent divergence B. Paralellism C. Convergence D. Stasis 2. The cryptic species complex of Stygocapitella subterranea is presumably under “morphological stasis” i. e. extreme conservation of morphology 3. Cryptic species have far reaching consequences to many fields of biology and will help us understand the natural world José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
Acknowledgments THANK YOU FOR YOUR ATTENTION Torsten H. Struck José Cerca | University of Oslo| @cryptic_omics | Forbio Annual Meeting 2018
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