...). Then, GPS tracking of experimental (PHZ-treated) and control (saline-treated) gulls during the incubation period provided no support for reduced or suspended engagement in energetically costly activities (long-distance foraging trips) by experimental birds. Instead, we found evidence for fine-scale...

...Samuel P. Caro; Ségolène Delaitre; Bruno Buatois; Francesco Bonadonna; Jessica L. Graham ABSTRACT Many organisms rely on environmental cues to predict and anticipate the annual optimal timing of reproduction. In insectivorous birds, preparation for breeding often coincides with the time vegetation...

... and fluid biomechanics, rendering it useful to understand general principles across disciplines. The different shapes of the bill across bird species result in functional and mechanical trade-offs, thus representing a microcosm of many broader form–function questions. Using examples from diverse studies, I...

...Chenxing Li; Chenyu Liu; Pingxia Hu; Xiyu Zheng; Ming Li; Jinsong Liu ABSTRACT For small birds to survive during seasonal acclimatization in temperate zones, regulation of body mass and thermogenesis is crucial. To determine the role of temperature and photoperiod in seasonal changes in body mass...

... (27°C) temperatures, we expected to observe an upregulation of pectoralis muscle and liver respiratory capacity that would be visible in mitochondrial adjustments in cold-acclimated birds. We also predicted that these adjustments would correlate with thermogenic capacity ( M sum ) and basal metabolic...

... 2022. Published by The Company of Biologists Ltd 2022 Highlighted Article: Analysis of the mechanism by which black woodpeckers can quickly release a stuck beak, by a quick succession of upper and lower beak retraction. Birds Pecking Kinematics Biomechanics Functional morphology...

...Lara do Amaral-Silva; Welex Cândido da Silva; Luciane Helena Gargaglioni; Kênia Cardoso Bícego ABSTRACT The febrile response to resist a pathogen is energetically expensive, while regulated hypothermia seems to preserve energy for vital functions. We hypothesized here that immune-challenged birds...

... . Physiol. Biochem. Zool. 91 , 904 - 916 . 10.1086/697380 Ruuskanen , S. , Darras , V. M. , Visser , M. E. and Groothuis , T. G. G. ( 2016 ). Effects of experimentally manipulated yolk thyroid hormone levels on offspring development in a wild bird species . Horm. Behav...

... or in the next generation are rare, especially in nutritional stress studies. This may be the case in part because of a long generation time for most birds, limiting our ability to track long-term consequences and transgenerational effects. Although there are challenges in long-term experiments and logistical...

... should be able to transmit the hormonal signals independent of their own hormonal status. However, the ability to regulate hormone transfer to the next generation is under debate. We studied the transfer of thyroid hormones (THs) to eggs in a bird model. We elevated thyroxine (T 4 , the prohormone...

... =5 males). Black-capped chickadees were acclimated to flight enclosures for a minimum of 2 weeks before experimentation. During both acclimation and experimentation periods, all birds were fed a mixture of mealworms ( Tenebrio molitor ), crickets ( Acheta domesticus ), sunflower seeds, safflower...

...) on captive house sparrows in order to investigate the consequences of short-term dehydration on baseline and stress-induced corticosterone levels. As expected, water-deprived birds displayed higher plasma osmolality and haematocrit. Additionally, water-deprived birds had lower defecation rates, suggesting...

... thus generate the observed diversity of external phenotypes. Starlings are generally dark birds despite iridescence in feathers, but 10% of species have evolved plumage pigmentation comprising bright colors that are known to be produced only by carotenoids. However, using micro-Raman spectroscopy, we...

... using stable isotope labelled androgens shows that maternal androgens in bird egg yolk are not taken up by the embryo during early incubation but rather are metabolized. Maternal effects Early hormone conversion Prenatal Birds Egg incubation Embryonic hormone uptake Exposure...

...Agata Bury; Jowita Niedojadlo; Edyta T. Sadowska; Ulf Bauchinger; Mariusz Cichoń ABSTRACT Physical aerobic activity is oxygen demanding, but – particularly for birds – there is still little understanding of how blood contributes to oxygen supply under various activity levels. In a two-factorial...

...Kang Nian Yap; Morag F. Dick; Christopher G. Guglielmo; Tony D. Williams ABSTRACT Despite widely held assumptions that hematocrit (Hct) is a key determinant of aerobic capacity and exercise performance, this relationship has not often been tested rigorously in birds and results to date are mixed...

... and an upregulation of oxidative phosphorylation efficiency. The aim of this study was to decipher mechanisms underlying the increased mitochondrial coupling efficiency reported in fasted birds. Mitochondrial oxidative phosphorylation activity, efficiency and membrane potential were measured in mitochondria isolated...

...-licence-1-1/ Summary: Behavioral choice tests reveal that blue petrels can recognize their own egg over a conspecific egg using odor cues. Olfactory communication Smell Birds Nesting Compared with visual and acoustic cues, the role of olfactory cues in avian behavior has long...

... isolated from pectoralis muscle. Results from long-term (4–5 months) naturally fasted chicks were compared with those from short-term (10 day) fasted birds. The respiratory activities of muscle fibres and isolated mitochondria were reduced by 60% and 45%, respectively, on average in long-term fasted chicks...

... water loss in birds. However, the mechanisms by which lipids are able to regulate CWL and how these mechanisms change with depth in the SC are poorly understood. We used attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) to measure lipid–lipid and lipid–water interactions...