Bruce Bagemihl - Biological Exuberance

84

See the profiles for more information and references. Among those 48 species in which homosexuality has been documented and quantitative information on nonbreeders is available, an average of half of the population (or of one sex) does not participate in reproduction (independent of homosexuality).

85

Squirrel Monkey (Baldwin and Baldwin 1981:295; Baldwin 1968:296, 311); Grizzly Bear (Craighead et al. 1995:139).

86

Chalmers, N. R. (1968) “Group Composition, Ecology, and Daily Activities of Free-Living Mangabeys in Uganda,” Folia Primatologica 8:247–62; Musk-ox (Gray 1973:170—71).

87

Searcy, W. A., and K. Yasukawa (1995) Polygyny and Sexual Selection in Red-winged Blackbirds , pp. 6, 169 (Princeton: Princeton University Press). For the other species, see the profiles and the discussion of sexual orientation in chapter 2.

88

Bennett, N. C. (1994) “Reproductive Suppression in Social Cryptomys damarensis Colonies—a Lifetime of Socially-Induced Sterility in Males and Females,” Journal of Zoology, London 234:25—39; Northern Elephant Seal (Le Boeuf and Reiter 1988:351). In mole-rats, large numbers of adults are “permanently” nonbreeding, while in Northern Elephant Seals, many males simply do not survive to the relatively advanced age when breeding typically begins, and of those that do, less than half actually breed.

89

Waser, P. M. (1978) “Postreproductive Survival and Behavior in a Free-Ranging Female Mangabey,” Folia Primatologica 29:142—60; Ratnayeke, S. (1994) “The Behavior of Postreproductive Females in a Wild Population of Toque Macaques ( Macaca sinica ) in Sri Lanka,” International Journal of Primatology 15:445–69; Bester, M. N. (1995) “Reproduction in the Female Subantarctic Fur Seal, Arctocephalus tropicalis,” Marine Mammal Science 11:362–75. For further examples, see profiles of species indexed under “postreproductive individuals.”

90

Marsh, H., and T. Kasuya (1991) “An Overview of the Changes in the Role of a Female Pilot Whale With Age,” in K. Pryor and K. S. Norris, eds., Dolphin Societies: Discoveries and Puzzles, pp. 281–85 (Berkeley: University of California Press).

91

Canada Goose (Collias and Jahn 1959:505). It is not the case that these birds were simply “trying harder” to reproduce, since some of these pairs produced eggs but failed to incubate them. Rather, it appears that as nonparents, they were able to “indulge” in more sexual behavior.

92

Birkhead, T. R., and A. P. Moller (1993) “Why Do Male Birds Stop Copulating While Their Partners Are Still Fertile?” Animal Behavior 45:105—18; Eberhard, Female Control, p. 395.

93

Wasser, S. K., and D. P. Barash (1983) “Reproductive Suppression Among Female Mammals: Implications for Biomedecine and Sexual Selection Theory,” Quarterly Review of Biology 58:513-38; Abbott, D. H. (1987) “Behaviorally Mediated Suppression of Reproduction in Female Primates,” Journal of Zoology, London 213:455–70; Reyer et al. 1986 (Pied Kingfisher); Macdonald and Moehlman 1982 (Wild Dogs); Jennions, M. D., and D. W. Macdonald (1994) “Cooperative Breeding in Mammals,” Trends in Ecology and Evolution 9:89–93; Creel and Macdonald 1995 (Wild Dogs); Solomon, N. G., and J.A. French, eds. (1997) Cooperative Breeding in Mammals , pp. 304—5 (Cambridge: Cambridge University Press).

94

American Bison (Komers et al. 1994:324 [see also discussion in chapter 4]); Pied Kingfisher (Reyer et al. 1986:216); tamarins and marmosets (Snowdon, C. T. [1996] “Infant Care in Cooperatively Breeding Species,” Advances in the Study of Behavior 25:643—89, especially pp. 677-80); other species (Solomon and French, Cooperative Breeding in Mammals , p. 5).

95

Rohrbach, C. (1982) “Investigation of the Bruce Effect in the Mongolian Gerbil ( Meriones unguiculatus ),” Journal of Reproduction and Fertility 65:411–17.

96

Bighorn Sheep (Geist 1971:181, 295); Red Deer (Clutton-Brock et al. 1983:371–72); Northern Quoll and other carnivorous marsupials (Dickman and Braithwaite 1992); Ruffed Grouse (Gullion 1981:379–80); Western Gull (Pyle et al. 1997:140,145); Spotted Hyena (Frank and Glickman 1994). For further discussion of the avoidance of reproduction because of its stressful and potentially injurious effects on the individual, see Hand 1981:140—42 (Laughing Gull).

97

Wagner, R. H. (1991) “The Use of Extrapair Copulations for Mate Appraisal by Razorbills, Alca torda ,” Behavioral Ecology 2:198—203; Sheldon, B. C. (1993) “Sexually Transmitted Disease in Birds: Occurrence and Evolutionary Significance,” Philosophical Transactions of the Royal Society of London , Series B 339:491–97; Hamilton, W. D. (1990) “Mate Choice Near or Far,” American Zoologist 30:341–52; Freeland, W. J. (1976) “Pathogens and the Evolution of Primate Sociality,” Biotropica 8:12—24. See also Birkhead, T. R., and A. P. Moller (1992) Sperm Competition in Birds: Evolutionary Causes and Consequences , p. 194 (London: Academic Press); Eberhard, Female Control, p. 111.

98

Watson, L. (1981) Sea Guide to Whales of the World , p. 174 (New York: E.P. Dutton).

99

For further discussion, see Peterson 1968, Gentry 1981 (Northern Fur Seal); Smith 1976:71 (Musk-ox).

100

Lee and Cockburn 1985:87—90, 163—70 (Carnivorous Marsupials).

101

Birkhead, T. R., and A. P. Møller (1993) “Sexual Selection and the Temporal Separation of Reproductive Events: Sperm Storage Data from Reptiles, Birds, and Mammals,” Biological Journal of the Linnaean Society 50:295-311; Birkhead and Møller, Sperm Competition in Birds ; Shugart, G. W. (1988) “Uterovaginal Sperm-storage Glands in Sixteen Species with Comments on Morphological Differences,” Auk 105:379—84; Stewart, G. R. (1972) “An Unusual Record of Sperm Storage in a Female Garter Snake ( Genus Thamnophis ),” Herpetologica 28:346-47; Racey, P. A. (1979) “The Prolonged Storage and Survival of Spermatozoa in Chiroptera,” Journal of Reproduction and Fertility 56:391-96; Baker and Bellis, Human Sperm Competition , pp. 42—43; Eberhard, Female Control, pp. 50—61, 167—69.

102

Sandell, M. (1990) “The Evolution of Seasonal Delayed Implantation,” Quarterly Review of Biology 65:23—42; York and Scheffer 1997:680 (Northern Fur Seal); Renfree, M. B., and J. H. Calaby (1981) “Background to Delayed Implantation and Embryonic Diapause,” in A. P. F. Flint, M. B. Renfree, and B. J. Weir, eds., Embryonic Diapause in Mammals, Journal of Reproduction and Fertility , supplement no. 29:1-9; Riedman, M. (1990) The Pinnipeds: Seals, Sea Lions, and Walruses , pp. 224-25 (Berkeley: University of California Press).

103

Greylag Goose (Lorenz 1979:74).

104

Francis, C. M., E. L. P. Anthony, J. A. Brunton, and T. H. Kunz (1994) “Lactation in Male Fruit Bats,” Nature 367:691-92.

105

McVean, G., and L. D. Hurst (1996) “Genetic Conflicts and the Paradox of Sex Determination: Three Paths to the Evolution of Female Intersexuality in a Mammal,” Journal of Theoretical Biology 179:199-211; King, A. S. (1981) “Phallus,” in A. S. King and J. McLelland, eds., Form and Function in Birds , vol. 2, pp. 107—47 (London: Academic Press).

106

Walrus (Fay 1982:39—40); Layne, J.N. (1954) “The Os Clitoridis of Some North American Sciuridae,” Journal of Mammalogy 35:357-66; Bray, K. (1996) “Size Is Nothing at All: Female Fish Has Novel Way to Adapt to Mate’s Lack of Penis,” BBC Wildlife 14(11):15.