Open questions in evolutionary ecology: do ostracods have the answers?

Abstract

Ostracods have many advantages as study organisms in the field of evolutionary ecology, especially their excellent fossil record. In this review, we consider issues of current interest in several areas, show where ostracods are already providing valuable insights and suggest new ways in which they might be used. We concentrate on non-marine ostracods. The evolutionary maintenance of sexual reproduction is one of the biggest unsolved questions in evolutionary biology and, because they show a wide diversity of asexual forms, non-marine ostracods can help to provide the answer. Recent advances from studies based on fossil data, ecology and molecular genetic approaches are reviewed. Other areas in which ostracods might be used more than they have been to date and that are considered more briefly are: sexual selection on the large and complex genitalia and spermatozoa, the causes and rates of speciation, the consequences of metapopulation structure and the factors determining the boundaries to the geographic ranges of species and the local diversity of species.