| testosterone and social and reproductive behaviour in aphelocoma jays. | when there is a direct relationship between testosterone level and payoff in reproductive success through aggression, testosterone levels should be elevated. elevated testosterone, however, has fitness costs, particularly a decreased tendency to display parental care. thus the pattern of testosterone secretion in males should vary with the social and mating system. western scrub-jays, aphelocoma californica woodhouseii, form monogamous pairs on territories during the breeding season. mexican jay ... | 1999 | 10564596 |
| the genus brueelia (phthiraptera: ischnocera: philopteridae) of north american jays and allies (aves: passeriformes: corvidae), with descriptions of five new species. | five new species of chewing lice in the genus brueelia kéler, 1936 , are described from north american jays and allies. they are brueelia mexicana n. sp. from aphelocoma woodhouseii cyanotis ridgway, 1887 ; brueelia bonnevillensis n. sp. from aphelocoma woodhouseii nevadae pitelka, 1945 ; brueelia diblasiae n. sp. from cyanocitta stelleri frontalis ( ridgway, 1873 ); brueelia tempestwilliamsae n. sp. from gymnorhinus cyanocephala wied-neuwied, 1841 ; brueelia mcnewae n. sp. from nucifraga columb ... | 2019 | 31805246 |