Genomics and the Future of the Conservation Genetics

A temporal framework for conservation biology

The tree used here is based on the history of sea turtles inferred from molecular sequence comparisons (Bowen & Karl 1996; Dutton et al. 1996). The process of conserving sea turtles may start with the systematists identifing seven extant species which require protection. Subsequently, ecologists identify the key habitat features that allow sea turtles to survive and thrive on an ecological timescale of a few tens of thousands of years. Finally, evolutionary biologists identify the raw materials for future prosperity and diversification. See figure 1

The temporal framework for setting conservation priorities allocates responsibilities in three distinct temporal spheres (past, present, and future) to three disciplines (systematics, ecology, and evolution). 

Reference:

1. Bowen, Brian W. Preserving genes, species, or ecosystems? Healing the Fractured Foundations of Conservation Policy. Molecular Ecology (1999), S5–S10.

2.    Bowen, B. W., Bass A. L., Soares, L. And Toonen, R. J. Conservation implications of complex population structure: lessons from the loggerhead turtle (Caretta caretta). Mol. Ecol, Volume 14, Issue 8, pages 2389–2402, July 2005.

Differences in population genetic structuring as defined by nDNA and mtDNA assays can have profound implications for wildlife management.

For example, mtDNA assays indicate that each green turtle nesting population is a distinct management unit (Bowen et al. 1992; Norman et al. 1994; Allard et al. 1994; Lahanas et al. 1994; Encalada et al. 1996), but nDNA assays indicate little population genetic structuring among some regional nesting colonies (Karl et al. 1992; FitzSimmons et al. 1996b). Acting on mtDNA data alone, wildlife managers might conclude that each nesting population is effectively isolated from other regional nesting colonies.This perspective is correct in terms of female (egg laying) lineages, but would miss the potential genetic link between nesting colonies afforded by male reproductive behavior. In this case, concerns about inbreeding and reduced genetic diversity in small nesting colonies might be misplaced, because wildlife managers would be unaware that gametic exchange through males may connect regional nesting populations.

Reference:

3. Bowen, B. W. and W. N. Witzell (Editors). 1996. Proceedings of the International Symposium on Sea Turtle Conservation Genetics. NOAA Technical Memorandum NMFS-SEFSC-396. 173 pp.