Biological Exuberance: Animal Homosexuality and Natural Diversity

4. bird species in which males associate in “pairs” or form “partnerships” with other males for joint displays during heterosexual courtships, but in which no overt courtship or sexual behavior occers between such partners or other same-sex individuals (e.g., several manakins of the genera Chiroxiphia, Pipra, Machaeropterus, and Masius—note however that males in these species often court “female-plumaged. birds, the sex of most of which has not been determined, while in two other species, some of these individuals have been determined to be males; wild turkey; king bird of paradise and possibly other birds of paradise. For further references, see McDonald 1989: (007 and Trainer and McDonald 1993:779).

5. species in which the only form of documented “same-sex” activity involves individuals mounting het-crosexual copulating pairs, such that the mounting activity is not necessarily limited to like-sexed individuals or the same-sex motivation/orientation is not clear (e.g., camel and Dagg 1981:92], Buller’s albatross [Warham 1967:129]).

6. species in which the only same-sex activity is mounting that appears to be exclusively aggressive in character with no sexual component (e.g., collared lemming, degu, ground squirrel; of. Dagg 1984 and sources cited therein; see also chapter 3 for further discussion of aggressive or “dominance” mounting and the difficulty of distinguishing this from sexual mounting); and species in which the only same-sex activities are “affectionate” behaviors or “platonic” companionships unaccompanied by either signs of sexual arousal or overt courtship or sexual behaviors.

7. other inconclusive cases, such as species reported in secondary sources as exhibiting homosexuality but whose original sources do not definitively document same-sex activity (e.g., avocets, reported in Terres [1980:813], with no mention of source, as engaging in homosexual mounting; Makkink [1936] and Hamilton [1975]—the most comprehensive primary field studies of this species and the most likely sources for this information—describe ritual mountings and masturbation “eruptive copulations”] but no homosexual mounting).

Armitage, K. B. (1962) “Social Behavior of a Colony of the Yellow-bellied Marmut (Marmota flaviventris).” Animal Behavior 10:319-31; Armstrong, D. P. (1988) “Persistent Attempts by a Male Calliope Hummingbird, Stellula calliope, to Copulate with Newly Fledged Conspecifics,” Canadian Field-Naturalist 102:259—60; Bollinger, E. K., T. A. Gavin, C. J. Hibbard, and J. T. Wootton (1986) “Two Male Bobolinks Feed Young at the Same Nest,” Wilson Bulletin 98:154—56; Dagg, A. I. (1984) “Homosexual Behavior and Female-Wale Mounting in Mammals—a First Survey,” Mammal Review 14:155—85; Earlé, R. A. (1985) “A Description of the Social, Aggressive, and Maintenance Behavior of the South African Cliff Swallow Hirundo spilodera (Aves: Hirundinidae),” Navorsinge van die nasionale Museum, Bloemfontein 5:37—50; Gauthier-Pilters, H., and A. I. Dagg (1981) The Camel: Its Evolution, Ecology, Behavior, and Relationship to Man (Chicago: University of Chicago Press); Hardy, J.W. (1964) “Ringed Parakeets Nesting in Los Angeles, California,” Condor 65:445—47; Harms, K. E., and J.A. Ahumada (1992) “Observations of an Adult Hummingbird Provisioning an Incubating Adult,” Wilson Bulletin 104:369-70; Laurie, A. ( 1982) “Behavioral Ecology of the Greater One-horned Rhinoceros (Rhinoceros unicornis),” Journal of Zoology, London 196:307—41; Makkink, G. F. (1936) “An Attempt at an Ethogram of the European Avocet (Recurvirostra avosetta L.), With Ethological and Psychological Remarks,” Ardea 25:1-63; McDonald, D. B. (1989) “Correlates of Male Mating Success in a Lekking Bird with Male-Male Cooperation,” Animal Behavior 37:1007—22; Terres, J. K. (1980) The Audubon Society Encyclopedia of North American Birds (New York: Alfred A. Knopf); Trainer, J. M., and D. B. McDonald (1993) “Vocal Repertoire of the Long-tailed Manakin and Its Relation to Male-Male Cooperation,” Condor 95:769—81; Warham, J. (1967) “Snares Island Birds,” Notornis 14:122—39.

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