Thomas 9723770 Marine invertebrates often spawn eggs directly into the water column exposing the eggs to extremes of physical stress. The proposed research will explore how egg characteristics modulate the negative effects of physical stress on reproduction. This research will integrate biomechanics, electron microscopy, and a phylogenetic analyses. Three primary hypotheses will be addressed: ( 1 ) egg properties do not affect diffusion/dilution rates of eggs; (2) egg properties do not increase survival of eggs after spawning; (3) there is no causal relationship between gamete properties and physical stress. This research will examine a little examined constraint on the reproductive success of an economically important group of invertebrates, the echinoids. Understanding the factors that influence production of embryos, in this group, is fundamental to developing appropriate life history models and fisheries management plans.
