In contrast to the majority of vertebrate species, primary male parental care is common in fishes and encompasses a remarkable diversity of adaptations. Seahorses and pipefishes (Family Syngnathidae) exhibit some of the most specialized forms of paternal care in animals and so are ideally suited to the study of the evolution of male parental care. During mating, female syngnathids transfer eggs...

At concentrations between 1 to 10 mM, caffeine reduced the Ca-accumulating capacity of fragmented reticulum obtained from frog and rabbit muscle. With 8 mM caffeine enough Ca was released from frog reticulum to account for the force of the contracture. Caffeine did not affect all reticulum membranes equally. The fraction which was spun down at 2000 g was more sensitive than the lighter fraction...

A new species of Carex sect. Rhomboidales, C. jianfengensis, is described and illustrated from Hainan, China. The new species is similar to C. zunyiensis but differs in having involucral bracts sparsely hispid and with ca.1 cm long sheaths; inflorescence with 4 spikes, terminal spike ca. 2.5 cm long, lateral spikes 2-3.5 × 0.7-1 cm; staminate glumes narrowly ovate, ca. 5 mm; pistillate glumes t...

Previous studies have shown that Ca influx increased but Ca efflux did not change during the contracture of taenia coli induced in hypertonically added 40 mm potassium solution (1) and the results were supported by the others (2-6). Further, the movements of Ca in the muscle in high-K solution might be differently affected by ouabain and 2, 4-dinitrophenol during the abolition of the tonic tens...

The dwarf seahorse (Hippocampus zosterae) is widely distributed throughout near-shore habitats of the Gulf of Mexico and is of commercial significance in Florida, where it is harvested for the aquarium and curio trades. Despite its regional importance, the genetic structure of dwarf seahorse populations remains largely unknown. As an aid to ongoing conservation efforts, we employed three common...

6 1 Department of Biology 7 Universiteit Antwerpen 8 Universiteitsplein 1 9 B-2610 Antwerpen 10 Belgium 11 12 2 Département d’Ecologie et de Gestion de la Biodiversité 13 Muséum National d’Histoire Naturelle 14 57 rue Cuvier, Case postale 55 15 75231, Paris Cedex 5 16 France 17 18 3 Evolutionary Morphology of Vertebrates 19 Ghent University 20 K.L. Ledeganckstraat 35 21 B-9000 Gent 22 Belgium 2...

The delayed component of intramembranous charge movement (hump, I gamma) was studied around the contraction threshold in cut skeletal muscle fibers of the frog (Rana esculenta) in a single Vaseline-gap voltage clamp. Charges (Q) were computed as 50-ms integrals of the ON (QON) and OFF (QOFF) of the asymmetric currents after subtracting a baseline. The hump appeared in parallel with an excess of...

Sex-role reversal occurs when females compete more intensely than males for access to mates. In this paper, we survey the occurrence of sex-role reversal in vertebrates: we focus on behavioural aspects of sex-role reversal and we examine possible endocrinological correlates of this phenomenon. The best documented cases among vertebrates of sex-role reversal occur in fish and birds. In nearly al...

The marine ornamental fish trade began in the 1930s in Sri Lanka, spread to Hawaii and the Philippines in the 1950s, and expanded to a multi-million dollar industry in the 1970s with fisheries established throughout the tropical Pacific, Indian and Atlantic Oceans. Currently, 45 countries supply global markets an estimated 14-30 million fish annually, with an import value of US$28-44 million. T...

Using area under the contracture curve to quantitate contractures, the diffusion coefficient of calcium ions within the frog toe muscle during washout in a calcium-free solution and subsequent recovery after reintroduction of calcium to the bathing solution was calculated to be about 2 x 10(-6) cm(2)/sec. The diffusion coefficient measured during washout was found to be independent of temperatu...