In aggressive communication, the interests of signalers and receivers are directly opposed,
presenting a challenge to the maintenance of reliable signaling. Index signals, whose …

During the last decade, evidence from a number of studies has suggested systematic
deviations from a 1: 1 primary sex ratio in birds, in spite of the fact that birds have …

We recorded parental provisioning rates of Varied Tits (Poecile various) at different altitudes
(n= 17, 7, and 11 nest boxes at 300, 900, and 1,400 m, respectively) to examine if males and …

Differing intensities of predation pressure can affect the evolution of life history traits in island
and mainland populations. We found extremely low nesting success in an insular …

In order to understand evolution in life history strategies, it is useful to compare breeding
parameters among closely related species and/or different habitats within the same species …

When the reproductive value of sons differs from that of daughters, selection will favor
broods biased toward the sex that can provide greater fitness benefits. In species where …

Abstract Theory, empirical examples, and recently, proximate mechanisms point to the
possibility of adaptive sex ratio adjustment in various organisms. General predictions state …

We determined the dominance hierarchy in competition for refuges by the xanthid crabs
Panopeus simpsoni, Eurypanopeus depressus, Rhithropanopeus harrisii, and juvenile …

The article presented evidence to support the observation that the color of the cheek patches
varies greatly in Parus varius namiyei, whereas it varies much less in varius and owstoni …

Animals use agonistic signals to mitigate the cost of conflict over resources. Bird song has
long been thought to function as an agonistic signal in songbirds. Many songbird species …