Evolution of basal metabolic rate in bank voles from a multidirectional selection experiment

Abstract

A major theme in evolutionary and ecological physiology of terrestrial vertebrates encompasses the factors underlying the evolution of endothermy in birds and mammals and interspecific variation of basal metabolic rate (BMR). Here, we applied the experimental evolution approach and compared BMR in lines of a wild rodent, the bank vole (Myodes glareolus), selected for 11 generations for: high swim-induced aerobic metabolism (A), ability to maintain body mass on a low-quality herbivorous diet (H) and intensity of predatory behaviour towards crickets (P). Four replicate lines were maintained for each of the selection directions and an unselected control (C). In comparison to C lines, A lines achieved a 49% higher maximum rate of oxygen consumption during swimming, H lines lost 1.3 g less mass in the test with low-quality diet and P lines attacked crickets five times more frequently. BMR was significantly higher in A lines than in C or H lines (60.8, 56.6 and 54.4 ml O 2 h 21 , respectively), and the values were intermediate in P lines (59.0 ml O 2 h 21 ). Results of the selection experiment provide support for the hypothesis of a positive association between BMR and aerobic exercise performance, but not for the association of adaptation to herbivorous diet with either a high or low BMR.

Limits to sustained energy intake. XXIII. Does heat dissipation capacity limit the energy budget of lactating bank voles?

“…Certainly, this aspect should also be considered in further studies applying such a manipulation. We expected that voles from the A-lines, which are characterised by increased BMR and daily FC rates compared with unselected C-lines (Koteja et al, 2009;Sadowska et al, 2015), would also have increased peak-lactation energy budgets, which could lead to a distinct reaction to the shaving manipulation. Interpretation of the results was complicated by the fact that A-line females were about 3 g heavier than C-line ones.…”

“…The metabolic rates were measured as the rate of oxygen consumption (ml O 2 h −1 ) similar to Sadowska et al (2015), with an open-flow, positive pressure respirometry system (design 1b in Koteja, 1996c) based on FC-2 and CA2-2A analysers (Sable Systems, Las Vegas, NV, USA). Oxygen consumption was recorded for about 4 h (after a 2 h period of food deprivation), sequentially on four channels.…”

“…Voles from the A-lines have a higher basal metabolic rate (BMR), daily food consumption and home-cage locomotor activity than animals from unselected C-lines (Koteja et al, 2009(Koteja et al, , 2011Sadowska et al, 2015). An analysis of complete transcriptomes from heart and liver revealed modified SNP (single nucleotide polymorphism) allele frequencies and modified expression levels of several genes encoding enzymes involved in carbohydrate and lipid metabolism (Konczal et al, 2015).…”

Resting vs. active: a meta‐analysis of the intra‐ and inter‐specific associations between minimum, sustained, and maximum metabolic rates in vertebrates

“…) and correlated responses to selection (Książek, Konarzewski & Łapo ; Sadowska et al . ) also provide equivocal results. No consensus seems to emerge because studies focus on different taxonomic groups (from fish to birds and mammals), metabolic traits (VO 2 max, Msum, and DEE) and levels of organization (intra‐ vs. inter‐specific).…”

Reproduction is not costly in terms of oxidative stress

“…measured without the cost of thermoregulation) and four non-selected (control) lines. Females from the selected lines had 45% higher mass-corrected maximum metabolic rates than control females (generation 13; Konczal et al, 2015), 10% higher mass-corrected basal metabolic rates (generation 11; Sadowska et al, 2015) and about 20% higher mass-corrected food consumption measured at 20°C (generations 11 and 18; G. Dheyongera and K. Grzebyk, unpublished results). In the main colony, the average litter size at weaning in generations 12 and 14 (used in this study) was 5.3 and 4.8 in the selected and control lines, respectively (values averaged from subsequent litters, typically litters 1-3, and the two generations; P.K., unpublished results).…”