Survival Sex Research Articles

Ecological correlates of lion social organization (Panthera leo)

Data on lion home range size, pride size, density, group size, cub survival, litter size and adult sex ratio were extracted from studies carried out in 10 habitats. The data were compared with five measures of food supply: mean prey biomass, prey biomass during the season of greatest abundance, prey biomass during the season of least abundance, biomass of middle‐sized prey species (i.e. those with mean adult live‐weights between 50 and 250 kg), and the mean size of carcasses fed on by lions. The results indicated that range size is inversely correlated with the abundance of prey during the period of least abundance, but not with overall prey abundance. Range size showed no consistent variation with pride size or with minimum metabolic requirements. Pride size (measured in terms of average number of animals per pride and average number of adult females) and cub survival strongly correlated with lean season food abundance. No relationship was found between group size or litter size and any of the measures of food supply Adult sex ratio did not vary consistently with food supply or lion density, although the data did suggest that prides inhabiting small, circumscribed reserves may experience less inter‐male competition and this, in turn, may affect the adult sex ratio.

Analysis of multiple births in Japan. VI. Effects of gestational age and maternal age on growth rate of weight in triplets.

Body weight of triplet individuals at one year of age was analysed. Mean body weight was heavier in males than in females, and the heaviest in the first-born followed by the second-born and the third-born in this order, which were also seen in that at birth. The contribution of gestational age was greater than maternal age to the growth rate of total body weight from birth to one year of age.

Analysis of multiple births in Japan. II. Weight at birth of triplets and quadruplets.

Birth weight of 124 sets of triplets and 7 sets of quadruplets was analysed in relation to survival states, sex and birth order. Mean birth weight was higher in live, births than in stillbirths in both triplet and quadruplet individuals. Males had higher mean birth weight than females among live born triplets and among live and still born quadruplets. Mean birth weight was larger in unlike-sexed than in like-sexed triplets, suggesting a lower mean birth weight in monozygotic than in dizygotic or trizygotic triplets. Mean birth weight was decreased in the order of twin, triplet and quadruplet individuals.

Influence of temperature and humidity on survival, development period and adult sex ratio in Prostephanus truncatus (Horn) (Coleoptera, Bostrichidae)

Prostephanus truncatus (Horn) is an established pest of maize in Central America. but has been only rarely recorded from elsewhere. Development from hatching to adult was possible at every one of the 24 combinations of 6 temperatures and 4 relative humidities used. and the period required was shortest at 32°C 80% r.h. Rate of development was obviously slower at 35°C than 32°C, being similar to that observed for 25–27°C. At 22°C the rate of development was appreciably slower. Below 70% r.h. at all temperatures the developmental period increased markedly, but at 80% r.h. it was sometimes shorter and sometimes longer than at 70%. In general, mortality was low in the 27–32°C, 70–80% r.h. zone, but tended to increase at lower humidities and more extreme temperatures, especially 35°C. A developmental index combining both rate of development and mortality confirmed 32°C 80% r.h. as optimal. There was no evidence that the physical environment affected the sex ratio of emerging adults.

Early sexual experience and prostitution.

The authors compared several aspects of early sexual experience found in two earlier studies of prostitutes with results of research on "normal" women. The prostitutes had in common many negative experiences not found or found less often in other populations of young women. These include incestuous and/or coerced sex, lack parental guidance, intercouse at a young age, and few or no meaningful relationships with males. These women had discovered that sex could lead to a kind of status, even though that status is negatively labeled by the wider culture. In a society that values women on the basis of their sexuality, a woman who views herself as "debased" may see prostitution as a viable alternative--perhaps the only alternative.

Autosomal Trisomies and Partial Trisomy Syndromes (with Presentation of Two Cases of Partial Trisomy for E Group of Chromosomes)

The establishing of 46 chromosomes as the normal complement in man and the report of the sex chromatin bodies in buccal smears were followed by reports of trisomies and other abnormal patterns of the X and Y chromosomes in Klinefelter's and Turner's syndromes. Abnormal autosomal complements were described in mongolism, in the E-trisomy syndrome, the D-trisomy syndrome, in the Sturge-Weber syndrome, Waldenstrom's macroglobulinemia, benign congenital hypotonia, atrial septal defect and in the schizoid personality. Certain of these conditions, as well as the "oral-facial-digital" syndrome, were also found to exist as partial trisomies. The mechanism of a trisomy is one of non-disjunction and of partial trisomy translocation or insertion. Two cases of the partial trisomy in the E group are described; these are of especial interest because of the familial incidence, longer survival and male sex occurrence, features which are rarely seen in the full E-trisomy syndrome.