International Research Fellowship Program: The Transition Between Indirect- and Direct-Development: Early Development of the Sea Urchin

Zigler, Kirk, Durham NC

Investigators

Abstract

0202773 Zigler The International Research Fellowship Program enables U.S. scientists and engineers to conduct three to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four month research fellowship by Dr. Kirk S. Zigler to work with Dr. Harilaos A. Lessios at the Smithsonian Tropical Research Institute in Balboa, Panama and with Dr. R. A. Raff at Indiana University. The goal of this project is to understand the mechanisms by which development evolves. In sea urchins, it is known that numerous features of oogenesis and embryonic development have been modified in the evolution of direct-development from the ancestral mode of indirect-development. By exploiting a species whose development is intermediate between these two extreme modes of development, the Pis will seek to understand how the early steps of the evolutionary transition occurred. The work will focus on the sea urchin Clypeaster rosaceus, which develops as a facultatively feeding larva. The primitive state is the obligatory feeding pluteus larva. This species possesses some features of indirect-development (pluteus larva), and some of direct-development (large egg), combined with an intermediate life history (ability to develop either as a feeding pluteus or as a non-feeding pluteus). Dr. Lessios has worked extensively on sea urchin life history and phylogeny and Dr. Raff is one of the leaders in the field of evolutionary developmental biology.