If inbreeding is the dominant mechanism, then the simulations indicate that consanguineous mating would have to be vastly more common than is predicted for most realistic populations, and if heterosis provides the answer, there need to be many more polymorphisms with major fitness effects and higher levels of linkage disequilibrium than are generally assumed.
A new procedure, based on a variance components analysis using generalized mixed effects models, is proposed, which concludes that effort should be directed at marking more individuals monitored over long periods at the expense of the sampling rate per individual.
Examination of three long–lived vertebrates, the long–finned pilot whale, the grey seal and the wandering albatross reveals significant negative relationships between parental similarity and genetic estimates of reproductive success, uncovering a selective pressure that favours not only inbreeding avoidance, but also the selection of maximally dissimilar mates.
It is concluded that in the deer population fitness measures expressed early in life do not show evidence of inbreeding depression, but they do showEvidence of heterosis, possibly as a result of population mixing.
This work analyzed the effect of density, extrinsic climatic fluctuations, and demography on the irregular pattern of population crashes of Soay sheep on the St. Kilda archipelago, United Kingdom.
It is demonstrated how earlier emergence from hibernation and earlier weaning of young has led to a longer growing season and larger body masses before hibernation, and this helps explain how a shift in phenology can cause simultaneous phenotypic and demographic changes.
The results suggest that problems associated with short-lived undesirable species may be exacerbated in regions where climate variability decreases, and that taxonomic affiliation has little power to explain sensitivity to increasing variability once longevity has been taken into account.
Through simulation, it is demonstrated that the timing of bad weather within a period of mortality can have an important modifying influence on intraspecific competition for food, revealing an interaction between climate and density dependence that the use of large-scale climatic indices or inappropriate local weather variables might obscure.
It is shown that the number of camera days/tiger photograph correlates with independent estimates of tiger density, a statistic that is particularly useful for estimating the population density of species that are not individually identifiable.
A hierarchical analytical approach is developed—using generalized linear mixed‐effects modeling of time series of home range sizes—that allows variance in home range size to be decomposed into components due to variation in temporal, spatial, and individual‐level processes, also facilitating intra‐ and interspecific comparative analyses.