The newly sequenced mitochondrial genomes of 107 Asian swamp buffalo (Bubalus bubalis carabensis) allowed the reconstruction of the matrilineal divergence since ~900 Kya. Phylogenetic trees and Bayesian skyline plots suggest a role of the glacial periods in the demographic history of swamp buffalo. The ancestral swamp-buffalo mitogenome is dated ~232 ± 35 Kya. Two major macro-lineages diverged during the 2nd Pleistocene Glacial Period (~200–130 Kya), but most (~99%) of the current matrilines derive from only two ancestors (SA1′2 and SB) that lived around the Last Glacial Maximum (~26–19 Kya). During the late Holocene optimum (11–6 Kya) lineages differentiated further, and at least eight matrilines (SA1, SA2, SB1a, SB1b, SB2a, SB2b, SB3 and SB4) were domesticated around 7–3 Kya. Haplotype distributions support an initial domestication process in Southeast Asia, while subsequent captures of wild females probably introduced some additional rare lineages (SA3, SC, SD and SE). Dispersal of domestic buffaloes created local population bottlenecks and founder events that further differentiated haplogroup distributions. A lack of maternal gene flow between neighboring populations apparently maintained the strong phylogeography of the swamp buffalo matrilines, which is the more remarkable because of an almost complete absence of phenotypic differentiation.

The value of phenotypic plasticity in energy metabolism and behavioral patterns in response to variations of food availability was handled in adult male voles (Eothenomys miletus) acclimated to random food deprivation (FD) for 4 weeks. During this period, in which voles were fed ad libitum for a randomly assigned 3 days each week, changes in body mass, food intake, resting metabolic rate (RMR), non-shivering thermogenesis (NST) and serum leptin levels were measured. Behavioral observations were made to examine behavioral patterns including activity, feeding, grooming and resting behaviors. The results showed that food intake and gastrointestinal mass increased significantly, but RMR and NST decreased significantly in the FD group compared to the control group. Moreover, the FD group had a significantly higher percentage of feeding behavior and lower activity than those in control group. In addition, serum leptin levels were positively correlated with body fat mass, but showed no significant differences between FD and the control group. These results suggest that E. miletus can compensate for an unpredictable reduction of food availability by engaging in an energetic strategy related to food intake and a decrease in energy expenditure associated with RMR, NST plus general activity, together with the mobilization of body fat as well as the adjustment of the gastrointestinal tract, which consequently play an important role in adaptations to food shortage in unpredictable environments.

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To test the hypothesis that mammals that show decrease in body mass under short-day condition should be resistant to highfat induced obesity, we traced the changes of energy balance in a wild rodent, Apodemus chevrieri, which were acclimated to either long day [16 light (L):8 dark (D), LD] or short day (8 L:16D, SD) and fed either a low-fat diet (LFD) or high-fat diet (HFD) in each photoperiodic manipulation. We found that A. chevrieri was not resistant to high-fat diet-induced obesity, and SD, not HFD, induced the elevation in basal metabolic rate (BMR), nonshivering thermogenesis (NST) and uncoupling protein-1 (UCP1) content in brown adipose tissue (BAT). HFD caused the increase in apparent digestibility and body fat mass, and the decrease in energy intake in both LD and SD A. chevrieri. The enhancement of energy absorption associated with small intestine tissue recruitment can compensate the lower energy intake, which may contribute to the highfat diet-induced body fat deposition. Thus, a decrease in body-weight gain without resistance to high-fat induced obesity implies an evolutionary and adaptive mechanism, which is a benefit for their winter survival.