Plasma metabolites provide information about the physiological state and fuel use of birds, and have been used for predicting refueling rates of birds during migratory stopovers. However, little is known about the effect of diet on metabolite concentrations in small songbirds. We investigated the effect of dietary macronutrient composition on lipid and protein metabolites in captive White-throa...

As colony-specific wintering ecology of small and medium-sized seabirds is poorly understood, it has been generally assumed that winter conditions have the same effect on all individuals from any given colony. However, advances in global positioning technology now allow researchers to investigate movements of smaller seabirds. We tracked black-legged kittiwakes Rissa tridactyla using geolocator...

Because bird species are lost when forests are fragmented into small parcels, trees that depend on fruit-eating birds for seed dispersal may fail to recruit seedlings if dispersal agents disappear. We tested this prediction in rainforest in the East Usambara Mountains of Tanzania, by using the endemic tree Leptonychia usambarensis (Sterculiaceae) and birds that disperse its seeds. We investigat...

this study was conducted to investigate the effects of different levels of zinc sulfate and chromium picolinate on performance, body temperature, carcass characteristics, tibia ash and serum biochemical parameters of japanese quails under heat stress condition. the birds (n = 540; 7-d-old) were randomly assigned to 9 treatment groups consisting of 3 replicates of 20 birds each in a 3 × 3 factor...

Ci.—Aspen stands and riparian areiis are important to breeding birds in ihe southwestern U.S. because they provide tesources such as food atid shelter. We investigated how this importance varies throughoul the year for bolh resident and migratory birds. We sampled hitds in 96 sites, half in small isolated aspen stands and half in the ponderosa pine forest in northern Ariirona thiring tlie sumiu...

We describe an exquisitely preserved new avian fossil (BMNHC-PH-919) from the Lower Cretaceous Yixian Formation of eastern Inner Mongolia, China. Although morphologically similar to Cathayornithidae and other small-sized enantiornithines from China's Jehol Biota, many morphological features indicate that it represents a new species, here named Junornis houi. The new fossil displays most of its ...

Frugivores are highly variable in their contribution to fruit removal in plant populations. However, data are lacking on species-specific variation in two central aspects of seed dispersal, distance of dispersal and probability of dispersal among populations through long-distance transport. We used DNA-based genotyping techniques on Prunus mahaleb seeds dispersed by birds (small- and medium-siz...

Birds stand out from other egg-laying amniotes by producing relatively small numbers of large eggs with very short incubation periods (average 11-85 d). This aspect promotes high survivorship by limiting exposure to predation and environmental perturbation, allows for larger more fit young, and facilitates rapid attainment of adult size. Birds are living dinosaurs; their rapid development has b...

Small ribozymes have been regarded as living fossils of a prebiotic RNA world that would have remained in the genomes of modern organisms. In this study, we report the ultraconserved occurrence of hammerhead ribozymes in Amniota genomes (reptiles, birds and mammals, including humans), similar to those described previously in amphibians and platyhelminth parasites. The ribozymes mapped to intron...

To identify a blood test that can differentiate cardiac from skeletal muscle injury in animals, we compared tissue reactivities for various species with the use of an immunoassay for human cardiac troponin I (cTnI). Tissue reactivity varied as a function of the homology of tissue troponin with human cTnI. Cardiac reactivity in large mammals was equivalent to cTnI, 9.8 +/- 0.6 mg/g, and was 2-fo...