Parental care is assumed to be costly in that it requires sustained, high-intensity activity
sufficient to cause costs of reproduction (decreased survival and future fecundity of parents) …

How hard do birds work during parental care, chick rearing, or provisioning of their
nestlings? And if birds do work hard, can we detect a physiological signature of individual …

Although physiological traits and phenology are thought to be evolved traits, they often show
marked variation within populations, which may be related to extrinsic factors. For example …

Costs of reproduction are an integral and long-standing component of life-history theory, but
we still know relatively little about the specific physiological mechanisms underlying these …

Investment in reproduction and postzygotic parental care is an energetically costly yet
fundamental aspect of the life-history strategies in many species. Recently, oxidative stress …

There is considerable interest in why the process of aging varies between individuals, both
in humans and other animals. However, in animals, aging in terms of survival (demographic …

Birds breeding in agricultural landscapes contend with potential reductions in prey
availability that may alter behavior and incur physiological costs. Individuals may need to …

In social systems with alternative reproductive tactics, sneakers face a higher level of sperm
competition than harem males and hence are predicted to allocate more resources to …

Cold acclimatization (phenotypic adjustments to cope with cold conditions) is an imperative
requirement for birds living at high latitudes during the cold depths of winter. Despite the …

Background Plasmodium parasites may affect the oxidative status of their hosts, defined as
the balance of pro-oxidant compounds and antioxidant defences in an organism. An …