Bigger is not always better: Viability selection on body mass varies across life stages in a hibernating mammal.

Body mass is often viewed as a proxy of past access to resources and of future survival and reproductive success. Links between body mass and survival or reproduction are, however, likely to differ between age classes and sexes. Remarkably, this is rarely taken into account in selection analyses.

Is the propensity to emit alarm calls associated with health status?

The production and structure of animal signals may depend on an individual's health status and may provide more than one type of information to receivers. While alarm calls are not typically viewed as health condition dependent, recent studies have suggested that their structure, and possibly their propensity to be emitted, depends on an individual's health condition and state. We asked whether the propensity of yellow-bellied marmots () to emit calls is influenced by their immunological or parasite status, by quantifying both trap-elicited and natural calling rates as a function of their neutrophil-to-lymphocyte (NL) ratio, the presence of a blood borne trypanosome, and the presence of several intestinal parasites ( sp.