Comparative and experimental studies of developmental plasticity and evolution

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Over the long history of the earth, how did the extraordinary variety of animals and other organisms evolve to their present form?  How did new forms arise?  These are two of the big questions evolutionary biologists ask, and lively debate exists over the best answers.  Just as other scientists argue about whether each of us is most influenced by heredity or environment (the "nature vs. nurture" debate), evolutionary biologists argue about the relative influence of genetics and environment.  This debate extends back over 100 years.      My research attacks these larger evolutionary questions by studying selected animals in detail.  We focus mainly on marine animals, which gives us lots of leeway -- thousands of species to choose from!  We will study four subjects to better understand the roles genotype and environment play in controlling the forms of animals:  1) the remarkable ability of sea urchin larvae to clone themselves when food is abundant or suitable habitat scarce -- we were the first to discover this ability in the larvae of sea urchins, sand dollars and sea cucumbers, 2) the ability of barnacles and porcelain crabs to grow longer legs for more efficient filter feeding when water velocities are lower or individuals are more crowded -- we were the first to discover that leg length in barnacles varies rather precisely with wave action, 3) the effects of parent form and temperature on eye-side in an unusual flatfish species that sometimes has eyes on the right side and sometimes on the left, so we can better understand a remarkable geographic gradient:  in Japan 100% of fish are left-eyed whereas in California only 50% are!, and 4) the effects of handedness (preferred limb use- right or left side) on the development of morphological asymmetries in crab claws or the tubes of caddisfly larvae-- these studies could provide a breakthrough in our understanding of how some animals evolved conspicuously asymmetrical structures.      In most of our studies, will use both field and laboratory experiments to help us better understand the mechanisms by which animals change their form in response to conditions they experience during growth.