Rates of growth and development were measured for the first six molts following the crab 1 stage in the mud crab Eurypanopeus depressus. The genetic contribution to variation in growth rate, development rate, and shape was determined for each molt interval. Genetic variation in growth rate, measured as increases in both width and length, was evident at most molt intervals.
View Article and Find Full Text PDFBrazil and the southeastern United States have faunistic similarities and differences which are of fundamental interest to the environmental scientist. These similarities and differences provide natural experimental organisms and habitats which can provide answers to basic and applied questions. What are the lethal limits of organisms to environmental changes? How do animals functionally adjust to various ecological parameters? How have basic biological systems evolved in response to new environments? Although the comparative functional attributes of individual species has been stressed in this paper, knowledge of the comparative dynamics os is vitally needed before man can gain an understanding of how systems function, and, equally important, how to manage and manipulate coastal marine environments.
View Article and Find Full Text PDFLarvae of the trematode Zoogonus lasius are involved in most double infections of Nassarius obsoleta. The two most common trematode parasites of this snail do not occur together in double infections. Double infections were found in 14 of 340 infected snails in a total sample of 5025 snails.
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