Speciation can be seen as the establishment of reproductive barriers among species. Hybrid zones provide us with an ideal situation to study the process of speciation because the evolution of reproductive isolation is still in progress. Hybrids usually suffer reduced fitness (i.e. leading to post-zygotic isolation) although they may have higher or similar fitness as the parental species in some...

In a recent article Patrick Maher shows that the ‘depragmatised’ form of Dutch Book arguments for Bayesianism tend to beg the question against their most interesting anti-Bayesian opponents. I argue that the same criticism can be levelled at Maher’s own argument for Bayesianism. The arguments for Bayesianism in the literature fall into three broad categories. There are Dutch Book arguments, bot...

Geoff A. Parker Population and Evolutionary Biology Research Group, Nicholson Building, School of Biological Sciences, University of Liverpool, Liverpool, UK L69 3GS. Ever since Trivers [1] showed that parents and their offspring could be in conflict over the amount of parental investment, the evolution and maintenance of begging behaviour has been an area of increasing interest to evolutionary...

Avian brood parasites lay their eggs in the nests of other species (hosts) which incubate and rear the brood-parasite offspring. This reproductive strategy directly reduces the cost of reproduction (e.g. parental care) and, therefore, may be subject to natural selection. I discuss three additional advantages arising from the fact that host and parasite are different species and that, therefore,...

Across a range of species including humans, personality traits, or differences in behaviour between individuals that are consistent over time, have been demonstrated. However, few studies have measured whether these consistent differences are evident in very young animals, and whether they persist over an individual's entire lifespan. Here we investigated the begging behaviour of very young cro...

A dialectical conception of justification helps conciliationists about peer disagreement establish the symmetry considerations on which their account is premised. On this conception, appeals to personal or hidden forms evidence fail provide a breaker that would allow one dismiss conflicting opinion. Furthermore, act citing same repetitively tends illegitimately beg question against peer, no mat...

BACKGROUND Although gestural communication is widespread in primates, few studies focused on the cognitive processes underlying gestures produced by monkeys. METHODOLOGY/PRINCIPAL FINDINGS The present study asked whether red-capped mangabeys (Cercocebus torquatus) trained to produce visually based requesting gestures modify their gestural behavior in response to human's attentional states. Th...