Species of the limpet genus Siphonaria (Gastropoda: Euthyneura) are commonly found in the rocky intertidal, worldwide, except in the Arctic. In total, 205 species-group names are available and not permanently invalid. However, estimating the actual species diversity of Siphonaria has remained challenging, mainly because past authors have interpreted differently the variation of shell characters...

The components of total variation--biological, inter- and intra-individual, and analytical--of plasma lipids, lipoprotein lipids, and apolipoproteins A-I and B have been determined in a population of 44 healthy women, ages 18-35 years. Blood was sampled three separate times at three-month intervals, with no restrictions on diet or physical activity during these periods. The greatest inter-indiv...

Inter and intra-population variation in morphological traits, such as body size and shape, provides important insights into the ecological importance of individual natural populations. The radiation of Diaptomid species (~400 species) has apparently produced little morphological differentiation other than those in secondary sexual characteristics, suggesting sexual, rather than ecological, sele...