Population management They also can open opportunities to educate the public about the many intellectual gifts and aesthetic marvels of the natural world

Creationis telluris est gloria Dei ex opere Naturae (The Earth's creation is the glory of God as seen in Nature's works).

Carolus Linnaeus, preface to Systema Naturae

In the 1700s, Carolus Linnaeus (1759) devised a hierarchical system to rank and classify organisms. He did so without knowledge of evolution, presuming instead that static species (albeit modified occasionally by hybridization) had been present since the time of Creation. A century later, Charles Darwin (1859) identified natural selection as a creative but natural agent of adaptive evolution. He did so without a proper understanding of genetics, sometimes presuming that heredity involved miscible gemmules in the blood. Nearly a century later, in the mid-1900s, Aldo Leopold (1949) crafted a powerful environmental ethic based on ecological considerations. The extraordinary accomplishments of these three great scientists illustrate that systematics, evolutionary biology, and conservation science—three cornerstones of modern biodiversity research—can be (and often have been) practiced successfully without material input from the field of genetics. This is ironic because, fundamentally, evolution is genetic alteration through time, biodiversity is genetic diversity (including epigenetic and emergent phenomena), and nature's genetic diversity is what is being depleted in the current extinction crisis that has spurred the conservation movement.

A growing awareness of genetic operations and principles, beginning with the findings of Gregor Mendel (a younger contemporary of Darwin), contributed hugely to the ''modern evolutionary synthesis'' in the mid-1900s (Dobzhansky, 1937; Mayr, 1942; Stebbins, 1950). Nevertheless, until the 1960s at least, organismal phenotypes (such as various morphological and behavioral traits) continued to provide the vast majority of empirical data for biodiversity research. Only in the last half-century have biologists gained extensive direct access to the hereditary information embedded in the molecular structures of nucleic acids and proteins (Hillis et al., 1996; Avise, 2004). What have these molecular genetic data added to the evolutionary synthesis and to conservation efforts?

Much of the molecular revolution in evolutionary biology has focused on mechanistic connections between genotype and phenotype, i.e., on attempts to understand ''the genetic basis of evolutionary change'' (Lewontin, 1974). In particular, a relatively young but burgeoning field known as evolution-development ("evo-devo") addresses how the evolving genomes of diverse taxa are epigenetically modified and otherwise regulated during ontogeny to yield particular organismal phenotypes, including complex adaptations (Carroll et al., 2004; Avise and Ayala, 2007). The evo-devo paradigm will continue to motivate scientific interest and generate vast research opportunities for the foreseeable future.

Here, I discuss three other areas of opportunity for molecular genetics in evolutionary biology, specifically in the realms of phylogenetics and conservation. For each of these three topics in a discipline that I call ''biodiversity genetics,'' I first summarize conventional wisdom, but then I intend to be provocative by raising scientific proposals that currently are far from mainstream but nevertheless have the potential to invigorate and perhaps even reshape the biodiversity sciences.

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