The attainment of sexual maturity of the female mammal depends upon the endocrine function of the ovary but it has not been clearly demonstrated to which part of the gonad this is due. In a recent review Marshall (1) writes “It is not known what precise ovarian elements are responsible for the production of the hormone which is an excitant for the development of the female organs and characters...

Sexual maturity, temporal reproductive pattern, and recruitment of juveniles were examined for the penaeoid shrimp Artemesia longinaris sampled for five and a half years in a tropical locality off the coast of São Paulo (23o S), Brazil. Monthly samples were taken from January 1998 to June 2003 at depths between 5 and 45 m. Ovarian maturity was used to examine breeding in adult females. Recruitm...

A brief review of investigations carried out at IAMC-CNR Messina on the reproductive biology of farmed blackspot sea bream Pagellus bogaraveo, a new candidate species for aquaculture, is presented. Different aspects of sexuality, including hermaphroditism, gametogenesis, spermatozoal ultrastructure, maturity staging, seasonal development of gonads, and spawning in captivity, were studied. Prota...

The influence of body size and maturation on the responses in peak oxygen uptake (VO2) to a 12-week aerobic training and nutritional intervention in obese boys (n = 30; 10-16 years) was examined using multilevel allometric regressions. Anthropometry, sexual maturity status, peak VO2, and body composition were measured pre- and postintervention. Significant decrements for body mass, body mass in...

Ploidy elevation is increasingly recognized as a common and important source of genomic variation. Even so, the consequences and biological significance of polyploidy remain unclear, especially in animals. Here, our goal was to identify potential life history costs and benefits of polyploidy by conducting a large multiyear common garden experiment in Potamopyrgus antipodarum, a New Zealand fres...

Thresholds to sexual maturity—either age or size—are critical life history parameters. Usually investigated in short-lived organisms, these thresholds and interactions among age, size, and growth are poorly known for long-lived species. A 34-year study of captive green turtles (Chelonia mydas) that followed individuals from hatching to beyond maturity provided an opportunity to evaluate these p...

The aim of the present study was to investigate the reproduction of three species of kilka, including common, anchovy and bigeye kilka in the southeastern waters of Caspian Sea. This study was conducted during 2010 and 6476 specimens were fortnightly collected from fishing landing site. Body weight and fork length were measured. The samples were dissected and female gonads were weighed. Sexual ...

A large body of work on monkey cranial metrics (involving conclusions about interspecific variation, sexual dimorphism, and ontogeny) depends on the assumptions that growth effectively ceases with dental maturity and that intraspecific variation is negligible. We test these assumptions by examining variation in 39 measurements of 166 dentally mature Alouatta palliata skulls from animals found d...

Size at maturity, fecundity, and reproductive periodicity were estimated for the spotted ratWsh, Hydrolagus colliei (Lay and Bennett, 1839), oV the coast of California, Oregon, and Washington. Maximum body size and size at median maturity were greater for females than males. Skeletal muscle concentrations of the steroid hormones testosterone (T) and estradiol (E2) predicted similar, but slightl...