Longitudinal vocal records of 26 juvenile male cowbirds from 2 populations (Molothrus ater ater and Molothrus ater artemisiae) were analyzed to look for susceptibility to social influence from either female cowbirds or heterospecifics. Within each population, 1 group of males was individually housed with female conspecifics, and the other with pairs of canaries (Serinus canaria). Evidence was f...

In a longitudinal study, the authors housed wild-caught juvenile male cowbirds (Molothrus ater artemisiae) with female cowbirds or canaries (Serinus canaria) from August until May. The males were then exposed to 3 social contexts. Males housed with canaries directed more vocalizations to canaries than to female cowbirds. Males housed with female cowbirds vocalized most to other males. The data ...

Phylogenetic relationships among species and subspecies of the Canary Island endemic lizard genus Gallotia are inferred based on nucleotide sequences of fragments of 12S ribosomal RNA and cytochrome b mitochondrial genes. The four morphologically established species have also been recognized at the molecular level. Relative affinities among species follow an eastern-western geographic transect....

There is increased neuronal firing in the high vocal center (a motor nucleus) and other song nuclei of canaries, Serinus canaria, and zebra finches, Taeniopygia guttata, whenever these songbirds sing or hear song. These observations suggested that song perception involved sensory and motor pathways. We now show that the act of singing, but not hearing song, induces a rapid and striking increase...

Brazil has a wide diversity of exotic birds that were brought to this country during the European colonization. These animals are kept in captivity and, in some cases, in inadequate facilities, which may facilitate the introduction of pathogens, including gastrointestinal parasites. The purpose of this study was to identify the main gastrointestinal parasites that affect exotic birds living in ...