In addition to the observed high diversity of species in tropics, divergence among populations same exists over short geographic distances both phenotypic traits and neutral genetic markers. Divergence suggests great potential for evolution reproductive isolation eventual speciation. birds, song can evolve quickly through cultural transmission result regional dialects, which be a critical component variation female preference. We examined male behavioral responses local nonlocal dialects two...

Soundscapes pose both evolutionarily recent and long-standing sources of selection on acoustic communication. We currently know more about the impact human-generated noise communication than we do how natural sounds such as pounding surf have shaped signals over evolutionary time. Based signal detection theory, hypothesized that phenotypes will vary with anthropogenic background levels similar mechanisms cultural evolution and/or behavioral flexibility may underlie this variation. studied...

Anthropogenic noise imposes novel selection pressures, especially on species that communicate acoustically. Many animals—including insects, frogs, whales and birds—produce sounds at higher frequencies in areas with low-frequency pollution. Although there is support for animals changing their vocalizations real time response to (i.e. immediate flexibility), other evolutionary mechanisms learn remain largely unexplored. We hypothesize cultural signal structures less masked by a mechanism of...

Abstract The soundscape acts as a selective agent on organisms that use acoustic signals to communicate. A number of studies document variation in structure, amplitude, or timing signal production correspondence with environmental noise levels thus supporting the hypothesis are changing their signaling behaviors avoid masking. time scale at which respond is particular interest. Signal structure may evolve across generations through processes such cultural genetic transmission. Individuals...

Abstract Background noise can interfere with acoustic communication. Signal modifications have the potential to increase signal‐to‐noise ratios and reduce masking effect of noise. Immediate signaling flexibility, a type vocal plasticity, allows animals modify their signal optimize transmission depending on ambient conditions. Results from previous studies provide conflicting evidence about whether expression immediate flexibility is dependent upon signaler having prior experience noisy...

Summary Moult is critical for fitness many organisms several reasons: it allows growth and maintains the function of integument protection, thermoregulation communication. Feather moult in birds costly therefore typically does not overlap with migration or reproduction. In spring, rapid succession pre‐alternate moult, (if a migrant) breeding suggests that timing could constrain initiation breeding. A trade‐off between time spent moulting might also limit quality. The proximate basis well...

The Winter Food Limitation Hypothesis (WFLH) states that winter food abundance is a dominant source of population limitation migratory birds. Evidence accumulating long-distance birds wintering in tropical climates have high overwinter survival probabilities and mainly affects their fitness nonlethally by limiting energetic reserves necessary for successful reproduction. In contrast, the relative roles direct mortality vs. indirect effects caused not been investigated thoroughly on...

Anthropogenic noise presents a problem for acoustic communication in animal taxa around the world. Many animals respond by modifying their signals, sometimes along multiple axes, such as song structure, redundancy, or amplitude. To date, no study has assayed relative response of to axes signal variation, structure and amplitude, associated with anthropogenic levels. investigate impact potential adaptations on targeted receivers, we manipulated amplitude minimum frequency white-crowned...

Female preference for local cultural traits has been proposed as a barrier to breeding among animal populations. As such, several studies have found correlations between male bird song dialects and population genetics over relatively large distances. To investigate whether female choice could act nearby contiguous populations, we tested variation in explains genetic structure eight populations of rufous-collared sparrows (Zonotrichia capensis) Ecuador. Our study sites lay along transect,...

The incidence of extra-pair paternity (EPP) is highly variable across bird taxa. While EPP known to affect reproductive variance, the causes temporal variation in rates are poorly studied. Breeding density has often been proposed as an important factor influencing variation, but it received mixed support. Over a 5-year period we examined rate socially monogamous Grasshopper Sparrow (Ammodramus savannarum) population on restored grassland Maryland. Of 124 broods, 62.1% had young (EPY), and...

Abstract ∙ Many tropical birds have slow‐paced life history strategies, exhibiting lower metabolic rates, reduced annual investment in reproduction, and longer lifespans relative to at higher latitudes. Life strategies been relatively well documented adult individuals the tropics, but we know comparatively little about immature stage. Here examine of feather replacement (molt) fattening Rufous‐collared Sparrows (Zonotrichia capensis) a high elevation equatorial population, following...

Although the highest diversity of birds occurs in tropical regions, little is known about genetic mating systems most species. We describe microsatellite markers isolated chestnut-crested yuhina (Staphida everetti), endemic to island Borneo, and grey-throated babbler (Stachyris nigriceps), widely distributed across Southeast Asia. Both species belong avian family Timaliidae are highly social, putatively cooperatively breeding which helpers attend nests members their social group. obtained...