We have concluded that there is no evidence that sexual selection was a factor in the evolution of giraffe morphology and that the long neck of giraffes did not evolve as a weapon in males. The more likely selective advantage of a long neck was improvement of access to high-level browse. “
“Tigers Panthera tigris continue to decline despite the best efforts of the worldwide scientific and conservation communities. Prey depletion has been linked Selinexor research buy to this decline, but a clear definition of what constitutes preferred prey and preferred prey weight range does not exist. This is critical information if we are to assess tiger reintroduction potential, monitor unforeseen poaching
of predators and prey, and successfully conserve the species. Here we reviewed the available literature on tiger diet and prey availability and calculated Jacobs’s electivity index scores from 3187 kills or scats of 32 prey species. We found that wild boar and sambar deer are significantly preferred by
tigers, with red deer and barasingha likely to be significantly preferred also with a larger sample size. Prey body mass was the only variable that related to tiger prey preference with species weighing between 60 and 250 kg preferred by tigers yielding a ratio of predator to preferred prey of 1:1, which is similar to other solitary felids. This information can be used to predict tiger diet, carrying capacity and movement patterns, as it has been for Africa’s large predator guild, and has important XAV-939 order implications for tiger conservation throughout its distribution. “
“The African wild dog Lycaon pictus is endangered, with anthropogenic impacts, pack size dynamics and competing predators explaining its decline. Relative to solar and lunar events, analysis of diel activity in two parapatric Zimbabwean populations revealed behavioural plasticity
in response to human activity. In Hwange, human presence was low; in Nyamandlovu, human presence and persecution were high. In both populations, Lycaon frequently hunted by moonlight, with 3–4 lux of light restricting nocturnal hunting to 13 days/lunar month. With diurnal hunts commencing at ‘civil twilight begin’ and ending at ‘astronomical twilight end’, light intensity was confirmed MCE as a limiting factor. Nyamandlovu dogs exhibited behavioural plasticity, demonstrated by scattered rather than clumped organization when at rest, and masked the zeitgeber by utilizing evenings and moonlight for more days under suboptimal light conditions than did Hwange dogs. Significantly, different allocation of morning, evening and moonlight hunts between Hwange (47%, 36%, 15%) and Nyamandlovu (28%, 31%, 41%), reduced the temporal potential for human encounter by 64%, but increased this potential for hyaena and lion encounters by 70% and 37%, thus highlighting the trade-off of this switch.