Individual and Sexual Differences in Time to Habituate to Food-Stimuli Presentation of Potential Prey in Hyla Japonica

In samples taken monthly throughout the year the percentage of American smelt in Lake Ontario and Lake Erie containing cysts of Glugea hertwigi was 5.2% and 62.7% respectively. Sexual differences in incidence were observed, the significance of which was uncertain as results from the two lakes were contradictory.In male fish infection was almost entirely restricted to the digestive tract with few cysts in the liver, skin, and testes. In female fish the digestive tract and ovaries were similarly infected.Seasonal fluctuations in Glugea infection were obvious and seemed correlated with the gonadal cycle. In both sexes the highest parasite load corresponded with the onset of maturation.A striking difference in fecundity between the two smelt populations was attributed to the Glugea infection. In females parasite cysts replaced ovarian tissue, causing a reduction in the number of maturing eggs.

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Sexual Difference, Animal Difference: Derrida and Difference “Worthy of Its Name”

Hypatia ◽

10.1111/j.1527-2001.2009.01032.x ◽

2009 ◽

Vol 24 (2) ◽

pp. 54-76 ◽

Cited By ~ 3

Author(s):

Kelly Oliver

Keyword(s):

Sexual Difference ◽

Sexual Differences ◽

Binary Opposition ◽

Infinite Variety

I challenge the age-old binary opposition between human and animal, not as philosophers sometimes do by claiming that humans are also animals, or that animals are capable of suffering or intelligence, but rather by questioning the very category of “the animal” itself. This category groups a nearly infinite variety of living beings into one concept measured in terms of humans—animals are those creatures that are not human. In addition, I argue that the binary opposition between human and animal is intimately linked to the binary opposition between man and woman. Furthermore, I suggest that thinking through animal differences or differences among various living creatures opens up the possibility of thinking beyond the dualist notion of sexual difference and enables thinking toward a multiplicity of sexual differences.

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Sexual differences in the foraging behaviour of Magellanic Penguins related to stage of breeding

Emu - Austral Ornithology ◽

10.1071/mu11065 ◽

2012 ◽

Vol 112 (2) ◽

pp. 90-96 ◽

Cited By ~ 26

Author(s):

Andrea Raya Rey ◽

Klemens Pütz ◽

Gabriela Scioscia ◽

Benno Lüthi ◽

Adrián Schiavini

Keyword(s):

Foraging Behaviour ◽

Sexual Differences ◽

Magellanic Penguins

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Food Specialization By Individual Trout

Journal of the Fisheries Research Board of Canada ◽

10.1139/f72-248 ◽

1972 ◽

Vol 29 (11) ◽

pp. 1615-1624 ◽

Cited By ~ 91

Author(s):

James E. Bryan ◽

P. A. Larkin

Keyword(s):

Rainbow Trout ◽

Brook Trout ◽

Salvelinus Fontinalis ◽

Stomach Contents ◽

Cutthroat Trout ◽

Salmo Gairdneri ◽

Potential Prey ◽

Repeated Observation ◽

Size Growth ◽

Salmo Clarki

Analyses of stomach contents showed that the kinds of prey eaten by brook trout (Salvelinus fontinalis), cutthroat trout (Salmo clarki), and rainbow trout (Salmo gairdneri) were seldom distributed at random among the individuals. Repeated observation of food eaten by individuals in a stream and ponds showed that prey types were eaten in proportions which were characteristic for an individual.Specialization occurred on several different kinds of prey. Although the degree of specialization was higher during shorter intervals, the data suggested that some specialization persisted for half a year. There were no striking correlations between degree of specialization and other individual properties such as size, growth rate, weight of food, number of food items, previous specialization, or area of recapture.In addition to the observations on trout in relatively undisturbed habitats, a field experiment was conducted using laboratory-reared rainbow trout held in small ponds. The food of each trout in the experiment was sampled repeatedly. In analysis of variance, interaction among the individuals and kinds of prey eaten showed that food specialization occurred. Both the absolute and relative abundance of potential prey were constant during the experiment.

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