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Comparative phylogeographic studies often reveal disparate levels of sequence divergence between lineages spanning a common geographic barrier, leading to the conclusion that isolation was nonsynchronous. However, only rarely do researchers account for the expected variance associated with ancestral coalescence and among-taxon variation in demographic(More)
Populations of the ecologically important sea urchin Diadema antillarum suffered severe mass mortalities throughout the Caribbean. This mortality was first observed at Panama in January 1983; by January 1984 it had spread to the rest of the Caribbean and to Bermuda. The sequence of mortality events in most areas is consistent with the hypothesis that the(More)
To understand how allopatric speciation proceeds, we need information on barriers to gene flow, their antiquity, and their efficacy. For marine organisms with planktonic larvae, much of this information can only be obtained through the determination of divergence between populations. We evaluated the importance of ocean barriers by studying the(More)
The high biodiversity of tropical marine hotspots has long intrigued evolutionary biologists and biogeographers. The genus Haemulon (grunts) is one of the most important (numerically, ecologically, and economically) reef fish groups in the New World and an excellent candidate to test hypotheses of speciation and diversity generation in the Greater(More)
Bindin, a sea urchin sperm protein, mediates sperm-egg attachment and membrane fusion and is thus important in species recognition and speciation. Patterns of bindin variation differed among three genera that had been studied previously. In two genera of the superorder Camarodonta, Echinometra and Strongylocentrotus, both of which contain sympatric species,(More)
A latitudinal gradient in biodiversity has existed since before the time of the dinosaurs, yet how and why this gradient arose remains unresolved. Here we review two major hypotheses for the origin of the latitudinal diversity gradient. The time and area hypothesis holds that tropical climates are older and historically larger, allowing more opportunity for(More)
Bindin is a gamete recognition protein known to control species-specific sperm-egg adhesion and membrane fusion in sea urchins. Previous analyses have shown that diversifying selection on bindin amino acid sequence is found when gametically incompatible species are compared, but not when species are compatible. The present study analyzes bindin polymorphism(More)
Studies on the evolution of reproductive proteins have shown that they tend to evolve more rapidly than other proteins, frequently under positive selection. Progress on understanding the implications of these patterns is possible for marine invertebrates, where molecular evolution can be linked to gamete compatibility. In this study, we surveyed data from(More)
We conducted a phylogenetic survey of sea urchin retroviral-like (SURL) retrotransposable elements in 33 species of the class Echinoidea (sea urchins, sand dollars, and heart urchins). A 263-bp fragment from the coding region of the reverse transcriptase (RT) gene was amplified, cloned, and sequenced. Phylogenetic relationships of the elements isolated from(More)
Research on speciation of marine organisms has lagged behind that of terrestrial ones, but the study of the evolution of molecules involved in the adhesion of gametes in free-spawning invertebrates is an exception. Here I review the function, species-specificity, and molecular variation of loci coding for bindin in sea urchins, lysin in abalone and their(More)