References
- Altmann , J. 1974 . Observational study of behaviour: sampling methods . Behaviour , 49 : 227 – 267 .
- Birkhead , T. R. 1987a . Sperm competition in birds . Trends Ecol. Evol. , 2 : 268 – 272 .
- Birkhead , T. R. 1987b . Sperm-storage glands in a passerine: the Zebra Finch Poephila guttata (Estrildidae) . J. Zool. Lond. , 212 : 103 – 101 .
- Birkhead , T. R. 1988 . Behavioral aspects of sperm competition in birds . Adv. Study Behav. , 18 : 35 – 72 .
- Birkhead , T. R. , Atkin , L. and Møller , A. P. 1987 . Copulation behaviour of birds . Behaviour , 101 : 101 – 138 .
- Birkhead , T. R. , Pellat , J. and Hunter , F. M. 1988 . Extra-pair copulation and sperm competition in the Zebra Finch . Nature , 334 : 60 – 62 .
- Buffer Hrdy , S. and Williams , G. C. 1983 . “ Behavioral biology and the double standard. ” . In Social behavior of female vertebrates Edited by: Wasser , S. K. 3 – 17 . London : Academic Press: .
- Broekhuysen , G. J. 1959 . The biology of the Cape Sugarbird Promerops cafer (L.) . Ostrich suppl. , 3 : 180 – 221 .
- Bunn , D. S. and Warburton , A. B. 1977 . Observations on breeding Barn Owls . Brit. Birds , 70 : 246 – 256 .
- Burger , A. E. , Siegfried , W. R. and Frost , P. G. H. 1976 . Nest-site selection in the Cape Sugarbird . Zool. afr. , 11 : 127 – 158 .
- Cheng , M.-F. , Porter , M. and Ball , G. 1981 . Do Ring Doves copulate more than necessary for fertilization? . Physiol. Behav. , 27 : 659 – 662 .
- Craig , J. L. 1980 . Pair and group breeding behaviour of a communal gallinule, the Pukeko . Porphyrio p. melanotus. Anim. Behav. , 28 : 593 – 603 .
- Davies , N. B. 1985 . Cooperation and conflict among Dunnocks, Prunella modularis in a variable mating system . Anim. Behav. , 33 : 628 – 648 .
- Dawkins , R. 1976 . The selfish gene Oxford : Oxford University Press .
- Dewsbury , D. 1982 . Ejaculate cost and male choice . Am. Nat. , 119 : 601 – 610 .
- Edinger , B. B. 1988 . Extra-pair courtship and copulation attempts in Northern Orioles . Condor , 90 : 546 – 554 .
- Fitch , M. A. and Shugart , G. W. 1984 . “ Requirements for a mixed reproductive strategy in avian species. ” . In Am. Nat. 124 – 126 .
- Gowaty , P. A. and Mock , D. W. 1985 . Avian monogamy . Ornithol. Monogr. , 37 : 1 – 121 .
- Lack , D. 1968 . Ecological adaptations for breeding in birds London : Methuen .
- Lombardo , M. P. 1986 . Extrapair copulations in the Tree Swallow . Wilson Bull. , 98 : 150 – 152 .
- Lumpkin , S. 1981 . Avoidance of cuckoldry in birds: the role of the female . Anim. Behav. , 29 : 303 – 304 .
- Lumpkin , S. 1983 . “ Female manipulation of male avoidance of cuckoldry behaviour in the Ring Dove. ” . In Social behaviour of female vertebrates Edited by: Wasser , S. K. 91 – 112 . London : Academic Press: .
- Maynard Smith , J. 1977 . Parental investment: a prospective analysis . Anim. Behav. , 25 : 1 – 9 .
- McKinney , F. , Cheng , K. M. and Bruggers , D. J. 1984 . “ Sperm competition in apparently monogamous birds. ” . In Sperm competition and the evolution of animal mating systems 523 – 545 . New York : Academic Press: . Smith, f L
- McKinney , F. , Siegfried , W. R. , Ball , J. and Frost , P. G. H. 1978 . Behavioural specializations for river life in the African Black Duck (Anas sparsa Eyton) . Z. Tierpsychol. , 48 : 349 – 400 .
- Moore , M. C. and Kranz , R. 1983 . Evidence for androgen independence of male mounting behavior in the-crowned Sparrows ( . Zonotrichia leucophrys gambelii). Horm. Behav. , 17 : 414 – 423 .
- Phillips , R. E. 1972 . Sexual and agonistic behaviour in the Killdeer ( . Charadrius vociferus). Anim. Behav. , 20 : 1 – 9 .
- Power , H. W. and Doner , C. G. P. 1980 . Experiments on cuckoldry in the Mountain Bluebird . Am. Nat. , 116 : 689 – 704 .
- Robertson , A. 1986 . Copulation throughout breeding in a colonial accipitrid vulture . Condor , 88 : 535 – 539 .
- Seiler , W. and Güttinger , H.-R. 1988 . Testosteronkon-zentrationen und Fortpflanzungsverhalten beim Japanischen Mövchen (Lonchura striata var. domestica Estrildidae) . J. Orn. , 129 : 473 – 475 .
- Sims , M. E. , Ball , G. F. and Cheng , M.-F. 1987 . Sperm competition after sequential mating in the Ringed Turtle-Dove . Condor , 89 : 112 – 116 .
- Skead , C. J. 1967 . The sunbirds of southern Africa Cape Town : Balkema. .
- Summers-Smith , D. 1963 . The House Sparrow London : Collins .
- Trivers , R. L. 1972 . “ Parental investment and sexual selection. ” . In Sexual selection and the descent of man 1871–1971 Edited by: Campbell , B. 136 – 179 . Chicago : Aldine: .
- Van tienhoven , A. 1983 . Reproductive physiology of vertebrates, , 2nd ed. Ithaca : Cornell University Press .
- Westneat , D. F. 1987 . Extra-pair copulations in a re dominantly monogamous bird: observation of behaviour . Anim. Behav. , 35 : 865 – 876 .
- Wickler , W. 1967 . “ Socio-sexual signals and their intra-specific limitation among primates. ” . In Primate ecology Edited by: Morris , D. 69 – 174 . London : Weidenfeld & Nicolson: .
- Wickler , W. 1980 . Vocal duetting and the pair bond. I. Coyness and partner commitment. A hypothesis . Z. Tierpsychol. , 4 : 201 – 209 .
- Wickler , W. and Seibt , U. 1983 . “ Monogamy: an ambiguous concept. ” . In Mate choice Edited by: Bateson , P. 13 – 50 . Cambridge : Cambridge Univ. Press: .
- Wolf , L. L. 1975 . “Prostitution” behavior in a tropical hummingbird . Condor , 77 : 140 – 144 .