SPERM COMPETITION AND MODE OF FERTILIZATION IN THE GRASS GOBY ZOSTERISESSOR OPHIOCEPHALUS (TELEOSTEI : GOBIIDAE)
- M. Scaggiante, C. Mazzoldi, C. Petersen, M. Rasotto
- Biology
- 1999
Overall differences between males support the presence of differences in the intensity of sperm competition, with larger males performing nesting behaviour while smaller ones sneak spawnings.
Colourful male guppies produce faster and more viable sperm
- L. Locatello, M. Rasotto, J. Evans, A. Pilastro
- BiologyJournal of Evolutionary Biology
- 1 September 2006
It is found that males with relatively large areas of orange pigmentation had significantly faster and more viable sperm than their less ornamented counterparts, suggesting a possible link between dietary carotenoid intake and sperm quality.
Male traits associated with alternative reproductive tactics in Gobius niger
- M. Rasotto, C. Mazzoldi
- Biology
- 1 July 2002
Male black goby Gobius niger, adopting parental or sneaking tactics, differed in secondary sex traits (elongation of the 4th ray of the first dorsal fin and black nuptial colouration) thus allowing…
Individual adjustment of sperm expenditure accords with sperm competition theory
- A. Pilastro, M. Scaggiante, M. Rasotto
- BiologyProceedings of the National Academy of Sciences…
- 9 July 2002
Sperm expenditure is measured in two gobiid fishes, the grass and black goby, in which up to six sneakers can congregate around the nest of territorial males and release their sperm when females spawn to show that, in accordance with theory, sneaker males of both species release fewer sperm as the number of competitors increases.
Social organization and sexual pattern in the Mediterranean parrotfish Sparisoma cretense (Teleostei: Scaridae)
- M. de Girolamo, M. Scaggiante, M. Rasotto
- Environmental Science
- 5 November 1999
Histological and demographic data seem to indicate that, as in other species of this genus, prematurational sex-change occurs in a population of Sparisoma cretense L. at Lampedusa Island, Italy.
Variation pattern of sperm quality traits in two gobies with alternative mating tactics
- L. Locatello, A. Pilastro, R. Deana, A. Zarpellon, M. Rasotto
- Environmental Science
- 1 October 2007
The pattern of variation that is found in the investment of sperm numbers and sperm quality in goby territorial and sneaker males, supports the results found in other species of fish with alternative mating tactics, suggesting that ejaculate quality traits are usually not traded off one against the other when ejaculate effort is increased in response to increased levels of sperm competition.
The biology of a population of spined loach, Cobitis taenia L.
- A. Marconato, M. Rasotto
- Environmental Science
- 1989
A spined loach population inhabiting a small river in northern Italy was studied; at each age, females were larger than males and both sexes showed a marked seasonal pattern of growth with a high rate from May through November.
Tactic-specific differences in seminal fluid influence sperm performance
- L. Locatello, F. Poli, M. Rasotto
- BiologyProceedings of the Royal Society B: Biological…
- 22 March 2013
It is shown that cross interactions of sperm and seminal fluid may influence the fertilization success of competing ejaculates with males investing in both sperm and vaginal seminal fluid in response to sperm competition risk.
Ejaculate of sneaker males is pheromonally inconspicuous in the black goby, Gobius niger (Teleostei, Gobiidae).
- L. Locatello, C. Mazzoldi, M. Rasotto
- Biology, PsychologyThe Journal of experimental zoology
- 1 November 2002
The black goby, Gobius niger, shows alternative male mating tactics, i.e., parental and sneaker males, and the behavioral response of parental males to the ejaculates of males performing different reproductive tactics is measured.
Mating system and alternative male mating tactics in the grass goby Zosterisessor ophiocephalus (Teleostei: Gobiidae)
- C. Mazzoldi, M. Scaggiante, E. Ambrosin, M. Rasotto
- Environmental Science
- 12 December 2000
The ejaculate characteristics indicate that grass goby males have functionally polymorphic spawns: in fact sperm trails of larger males last longer and release fewer sperm than those of smaller males.
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