Regardless of colony size, less-related individuals were born in colonies located in the core of the agricultural plain, where we CHIR99021 quantified a higher level of human disturbance. In contrast, more related individuals were in colonies located in the marginal, less disturbed, agricultural area. Given the high philopatry of this species, our results are consistent with disruption of colony fidelity related to intensification of agricultural practices. We discuss the possible implications of long-term effects of genetic variability in small and disturbed colonies on fitness and population viability. “
“Small mammals that inhabit arid and temporally
unproductive environments use several methods to conserve energy. Here, we investigate the energetic role of sun basking in striped mice Rhabdomys pumilio from the Succulent Karoo desert in South Africa. We observed mice in front of their nests for 140 h and recorded the time they spent basking during the non-breeding (dry) and the breeding (wet) seasons. We measured temperature changes in model mice to provide an indication of the heat that
can be absorbed from the sun. Finally, we measured the oxygen consumption (V̇O2) of mice at their basking sites in the field both in the sun and in the shade. This was accomplished using a portable respirometry system with a metabolism chamber, which could be placed in and out of the sun. Observations showed that mice basked more often during the non-breeding than during the breeding season. During the former season, mice Celastrol spent an average of 11.9 ± 1.1 min (se) in the morning and 5.5 ± 0.5 min in the afternoon Dinaciclib mw per day basking. Within the metabolism chamber, V̇O2 decreased when the animal was in the sunshine compared with the shade. This effect occurred independent of the ambient temperature (Ta), indicating that a significant amount of radiant energy was absorbed from the sun. Basking may be an alternative to other energy-acquisition behaviours, such as foraging, which might be particularly useful at times when food is scarce. “
“The spiny tenrecs,
an endemic subfamily of Malagasy insectivores (Tenrecinae), are wide ranging and fairly conspicuous, yet long-term studies on free-ranging populations remain sparse. Basal to most eutherian mammals, they share many ecological and morphological traits with proposed eutherian ancestors. Understanding of their unusual life histories is therefore important to the understanding of mammalian evolution. Here we present the results of a 3-year study on a population of Setifer setosus in the dry deciduous forest of Western Madagascar. The annual activity cycle of this species includes a 5–7-month hibernation period, during the dry season, and a dramatic increase in body mass during the active season. Females, observed giving birth to up to three litters in a single season, entered hibernation later than males, after weaning their last litter.
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