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Indirect measures of reproductive effort in a resource-defense polygynous ungulate: Territorial defense by male guanacos
(Springer Tokyo, 2012-01)
Trade-offs between reproductive effort and activities that are likely to enhance survival have been studied extensively in harem defense ungulates. However, among resource defense systems, ecological determinants of the ...
Energy allocation to growth and reproduction in a viviparous lizard endemic to the highlands of the Andes, Argentina
(Wiley, 2015-09)
Individuals devote energy intake to growth, maintenance and reproduction, so knowing the way in which they allocate this energy between competing demands is essential to understand their relationship with the environment. ...
Avaliação da fertilidade e de possíveis defeitos estruturais externos sobre a prole de ratos machos expostos cronicamente ao arsênio
(2005-06-01)
Arsenic is an environmental pollutant that influences the male reproductive function, affecting the spermatogenesis process in the testis and causing alterations in the sperm. The objective of this work was evaluate the ...
Avaliação da fertilidade e de possíveis defeitos estruturais externos sobre a prole de ratos machos expostos cronicamente ao arsênio
(2005-06-01)
Arsenic is an environmental pollutant that influences the male reproductive function, affecting the spermatogenesis process in the testis and causing alterations in the sperm. The objective of this work was evaluate the ...
Dynamics of energy reserves and the cost of reproduction in female and male fiddler crabs
(Elsevier Gmbh, 2018-02)
The physiological costs of reproduction can be measured as the energy allocated to reproductive activities. In fiddler crabs, females allocate energy to vitellogenesis and brooding, whereas males perform expensive courtship ...
Slow life histories in lizards living in the highlands of the Andes Mountains
(Springer Heidelberg, 2017-11-17)
In the highlands of the Andes, lizards must balance precisely the allocation of energy for growth and reproduction to ensure their survival. We studied the individuals’ age, growth rates, age at sexual maturity, and maximum ...
Trade-offs in male display activity with lek size
(2016-09-01)
In lek mating systems, males aggregate and defend arenas where they display for females; females select and mate with a male and then solely raise their offspring. Generally, female visits and copulations increase and ...
Differential allocation in a gift‑giving spider: males adjust their reproductive investment in response to female condition
(BMC, 2021)
Background: When males are selective, they can either reject low-quality females or adjust their reproductive investment in response to traits that indicate female quality (e.g., body size or condition). According to the ...
Reproductive biology of an endemic Physalaemus of the Brazilian Atlantic forest, and the trade-off between clutch and egg size in terrestrial breeders of the P. signifer group
(British Herpetol Soc, 2010-07-01)
Physalaemus crombiei is a small foam-nesting frog endemic to the Atlantic forest. It is a member of the P signifer group known only from its type locality in Santa Teresa, State of Espirito Santo, and from another locality ...