Larvae of most marine invertebrates postpone metamorphosis in the absence of a suitable environment for the adult stage. Larvae of three marine gastropod species, Ih,anassa obsoleta (Say), CrepidulaJbrnicata (L.), and Bittium alternatunl (Say), differed in the potential durations of their delay periods and in their ultimate fates in the absence of preferred substratum for metamorphosis in the l...

Después de Hiroshima y Nagasaki, Polanyi advirtió que el libre mercado podía destruir la naturaleza especie humana. Las sociedades han combinado tres formas económicas básicas: redistribución, reciprocidad e intercambio. En postguerra, Estado bienestar conjugó mejoró los niveles vida. años ochenta se dio primacía absoluta al con base en procesa información asigna recursos mejor humanos las inst...

Subspecies have been considered artificial subdivisions of species, pattern classes, or incipient species. However, with more data and modern phylogenetic techniques, some subspecies may be found to represent true species. Mitochondrial DNA analysis of the polytypic snake, Elaphe obsoleta, yields well-supported clades that do not conform to any of the currently accepted subspecies. Complete nuc...

Eight NE Atlantic and Mediterranean species, which were originally assigned to the genus Schizoporella (Family Schizoporellidae) when introduced, are redescribed and stabilized by typification. Seven of these species are transferred to the bitectiporid genus Schizomavella: S. fischeri, S. glebula, S. neptuni, S. obsoleta, S. richardi, S. triaviculata, and S. triaviculata var. paucimandibulata, ...

no voucher); Lake Okeechobee at Fisheating Creek 39890). GEORGIA: Chatham Co.: Old Hwy 17 ('CAS 170408). Hernando Co.: Hwy 98 at Brooksville ('LSUMZ 45359). ('CAS 169468). Hillsborough Co.: Tampa, near USF Elaphe obsoleta spiloides. MISSISSIPPI: Smith Co.: 4 campus ('HCD 4886 and 4887, no vouchers). Palm mi. N Taylorsville, Leaf River ('LSUMZ 37983). Beach Co.: S of Lake Okeechobee ('LSUMZ 3790...

Many marine organisms spend the early part of their lives as larvae suspended in the water column before metamorphosing into benthic reproductive adults. Metamorphosis does not occur until a larva has become competent to respond to appropriate stimuli and after a suitable habitat for the young juvenile has been encountered. The gaseous neurotransmitter nitric oxide is thought to be important in...

Protein synthesis before and after fertilization in Zlyanassa obsoleta has been investigated. Unfertilized eggs do incorporate significant amounts of labelled amino acids into protein. However, fertilized eggs undergo an increase both in uptake and incorporation of labelled ammo acids into protein within 15 minutes of fertilization. Post-fertilization protein synthesis is sensitive to but not c...