Genus age, provincial area and the taxonomic structure of marine faunas

Paul G. Harnik, David Jablonski, Andrew Z. Krug, James W. Valentine

Research output: Contribution to journalArticlepeer-review

24 Scopus citations


Species are unevenly distributed among genera within clades and regions, with most genera species-poor and few species-rich. At regional scales, this structure to taxonomic diversity is generated via speciation, extinction and geographical range dynamics. Here, we use a global database of extant marine bivalves to characterize the taxonomic structure of climate zones and provinces. Our analyses reveal a general, Zipf- Mandelbrot form to the distribution of species among genera, with faunas from similar climate zones exhibiting similar taxonomic structure. Provinces that contain older taxa and/or encompass larger areas are expected to be more species-rich. Although both median genus age and provincial area correlate with measures of taxonomic structure, these relationships are interdependent, nonlinear and driven primarily by contrasts between tropical and extra-tropical faunas. Provincial area and taxonomic structure are largely decoupled within climate zones. Counter to the expectation that genus age and species richness should positively covary, diverse and highly structured provincial faunas are dominated by young genera. The marked differences between tropical and temperate faunas suggest strong spatial variation in evolutionary rates and invasion frequencies. Such variation contradicts biogeographic models that scale taxonomic diversity to geographical area.

Original languageEnglish (US)
Pages (from-to)3427-3435
Number of pages9
JournalProceedings of the Royal Society B: Biological Sciences
Issue number1699
StatePublished - Nov 22 2010

All Science Journal Classification (ASJC) codes

  • General Biochemistry, Genetics and Molecular Biology
  • General Immunology and Microbiology
  • General Environmental Science
  • General Agricultural and Biological Sciences


Dive into the research topics of 'Genus age, provincial area and the taxonomic structure of marine faunas'. Together they form a unique fingerprint.

Cite this