Search results for "UMAG"

Heterospecific female mimicry in Ficedula flycatchers

2014

Mimicry is a widespread phenomenon. Vertebrate visual mimicry often operates in an intraspecific sexual context, with some males resembling conspecific females. Pied flycatcher (Ficedula hypoleuca) dorsal plumage varies from the ancestral black to female-like brown. Experimental studies have shown that conspecific and heterospecific (collared flycatcher, F. albicollis) individuals of both sexes respond, at least initially, to brown individuals as if they were female. We quantified the perceptual and biochemical differences between brown feathers and found that brown pied flycatcher males are indistinguishable from heterospecific, but not from conspecific, females in both aspects. To our kno…

Phylogeny and species limits in the Palaearctic chiffchaffPhylloscopus collybitacomplex: mitochondrial genetic differentiation and bioacoustic eviden…

1996

Nucleotide sequences of the mitochondrial cytochrome b gene (1041 bp), analysis of vocalizations and behavioural evidence from zones of contact were used to reassess the species limits and phylogenetic relationships at the species and subspecies levels in the Phylloscopus collybita complex. A new classification is proposed which recognizes four biological species. Phylloscopus brehmii (Iberia) and P. canariensis (Canary Islands) are genetically and bioacoustically highly distinct. There is no mitochondrial gene flow between them or with P. collybita. The Mountain Chiffchaff P. sindianus (with subspecies sindianus and Iorenzii) is equally distinct genetically from southwest Asian subspecies …

Health parameters and sexual signalling in yearling black grouse males (Tetrao tetrix)

2006

Morphological and Biometric Features of Male BluethroatsLuscinia svecicain Central Iberia

2011

Summary. In order to test biometrics and plumage variability in bluethroats Luscinia svecica in central Iberia, 185 birds were captured in four areas (Sierra-Bejar, Sierra-Piedrahita, Sierra-Gredos and Sierra-Paramera). Older bluethroats were significantly larger than second calendar year birds in wing, tail, and total body lengths, but not in tarsus and bill lengths. A multivariate analysis of variance (MANOVA) and a principal component analysis (PCA) were used. Total body length only varied significantly between sampling areas: the birds from Sierra-Bejar were larger than those from Sierra-Gredos and Sierra-Paramera, but were similar to those of Sierra-Piedrahita. Birds with a white spot,…

Diversité génétique individuelle, différenciation morphologique et comportementale entres les sexes, patterns d'appariement et paramètres démographiq…

2013

Research in avian behavioral ecology is affected by a known bias in favour of temperate species despite the greatest diversity of tropical species and the radically remote natural conditions which make knowledge of temperate species hardly relevant to tropical species.We propose to reduce the lack of information about tropical birds through the study of a socially monogamous species, reproducing and defending an all-purpose territory all year round, the Zenaida dove, Zenaida aurita. We used monitoring data from a population of ringed birds in Barbados for six years. First, we focused on plumage coloration both to ascertain their sexually mono- or dichromatic nature and whether plumage colou…

Plumage colour and male-male interactions in the pied flycatcher

1993

Abstract Abstract. The influence of male colour on male-male interactions in the pied flycatcher, Ficedula hypoleuca , was studied using several types of field experiments. This species exhibits delayed plumage maturation, each male becoming more conspicuously black and white from the first to the second breeding summer. However, individual males vary even more, some old males being as brown as females. When territorial males were presented with a choice between brown and black male intruders (or brown males painted black) they directed more aggression towards the black males. Brown plumage did not help males obtain nestboxes close to other males. If anything browner males were at a disadva…

Fluctuating asymmetry and copulation success in lekking black grouse

1997

Abstract In lekking black grouse, Tetrao tetrix males at the centre of the leks obtain more copulations than males at the edges. We found that males with territories at the edge of the lek obtained fewer matings and also have the most asymmetric tarsi. However, when considering the tail ornament (the lyre) no correlation between asymmetry and mating success was found. Although females are unlikely to select males on the basis of tarsus symmetry, asymmetry in this trait may reflect male condition. We suggest that males in poor condition, as reflected by higher levels of fluctuating asymmetry in the tarsi, do not achieve central positions on the lek arena. This would account for the lower suc…

Individual color variation and male quality in pied flycatchers (Ficedula hypoleuca): a role of ultraviolet reflectance

2002

Bright coloration of males in many animal species has inspired researchers for more than a century. In this field study, we investigated whether color variation between individuals is related to individual quality in pied flycatcher (Ficedula hypoleuca) males in terms of arrival time at the breeding sites. In addition to traditional visual color scoring, plumage color was measured using spectroradiometric measurements between 320 and 700 nm. This range includes the near-ultraviolet waveband from 320 to 400 nm. Males that arrived earlier at breeding sites had higher proportional UV reflectance in the crown and mantle. The proportional UV reflectance in the crown and mantle was not related to…

Melanin-based colour polymorphism signals aggressive personality in nest and territory defence in the tawny owl (Strix aluco)

2013

Nest and territory defence are risky and potentially dangerous behaviours. If the resolution of life history trade-offs differs between individuals, the level of defence may also vary among individuals. Because melanin-based colour traits can be associated with life history strategies, differently coloured individuals may display different nest and territory defence strategies. We investigated this issue in the colour polymorphic tawny owl (Strix aluco) for which plumage varies from dark to light reddish melanic. Accordingly, we found that (1) our presence induced a greater response (flying around) from dark-coloured than light-coloured females and (2) dark reddish males suffered lower nest…

Energy reserves of the capercaillie Tetrao urogallus in finlan

1990

Abstract 1. 1. The size of energy reserves, distribution of fat stores and the fatty acid composition of subcutaneous and pericardial adipose tissue of capercaillie (Tetrao urogallus) were studied in 12 adult birds shot in Sept.–Oct. and in 8 birds shot in March. Furthermore 4 captive birds were killed in Sept. 2. 2. A capercaillie male can maintain or even increase its body weight during winter, but as shown in the present work it is not a result of increased fat content. 3. 3. In general, capercaillie seems to contain more stored energy in the form of fat than other tetraonids so far studied, except Svalbard ptarmigan. 4. 4. In males total fat content in percentage of body weight varied o…