Biological Exuberance: Animal Homosexuality and Natural Diversity

In many species, young may also be raised in heterosexual trios, i.e., family units with three parents in which only opposite-sex bonding is present between the adults. See chapter 5 for some examples.

18

For discussion of single parenting in animals where two (heterosexual) parents usually raise the young, as well as examples of other heterosexual parenting arrangements that deviate from the species-typical pattern, see chapter 5.

19

For additional discussion of male bias in biological studies, see chapters 3 and 5.

20

Rhesus Macaque (Altmann 1962:383; Lindburg 1971:69); Hamadryas Baboon (Abegglen 1984:63); Gelada Baboon (Bernstein 1970:94); Tasmanian Native Hen (Ridpath 1972:30); Gray-headed Flying Fox (Nelson 1965:546).

21

Pukeko (Jamieson and Craig 1987a:1251 ); Bonobo (Thompson-Handler et al. 1984:349; Kano 1992:187; Kitamura 1989:55—57); Stumptail Macaque (Chevalier-Skolnikoff 1974:101, 110); Red Deer (Hall 1983:278); Red-necked Wallaby (LaFollette 1971:96); Northern Quoll (Dempster 1995:29).

22

Pig-tailed Macaque (Oi 1990a:350—51): Galah (Rogers and McCulloch 1981); Pronghorn (Kitchen 1974:44).

23

Gorilla (Fischer and Nadler 1978:660—61; Yamagiwa 1987a:12, 1987b:37).

24

Pukeko (Jamieson and Craig 1987a:1251—52); Flamingo (C. E. King, personal communication). In Lesser Flamingos, however, the reverse appears to be true: males but not females achieve cloacal contact during their homosexual mounts (Alraun and Hewston 1997:176).

25

Japanese Macaque (Hanby 1974:838-40; Wolfe 1984:149; Fedigan 1982:143).

26

For further discussion of comparisons between animal and human homosexuality, see chapter 2.

27

These formulas are also used to estimate the number of bisexual/heterosexual trios in a population; see Conover and Aylor 1985:127 (Ring-billed Gull).

28

Kob (Buechner and Schloeth 1965); Long-tailed Hermit (Stiles and Wolf 1979). Likewise, up to 30 homosexual pairs of Herring Gulls have been counted in some locations—a relatively high number of same-sex associations to be present at one time—but in colonies that number more than 10,000 pairs, this amounts to less than I percent of the total number of pairs (Shugart 1980:426—27).

29

Same-sex courtship, sexual, pair-bonding, and /or parenting behaviors have been documented in the scientific literature in at least 167 species of mammals, 132 birds, 32 reptiles and amphibians 15 fishes, and 125 insects and other invertebrates, for a total of 471 species (see part 2 and appendix for a complete list). These figures do not include domesticated animals (at least another 19 species; see the appendix), nor species in which only sexually immature animals/juveniles engage in homosexual activities (for a survey of the latter in mammals, see Dagg 1984). For a number of reasons, this tally is likely to be an underestimate (especially for species other than mammals and birds, which are not as thoroughly covered): see chapter 3 for further discussion. It should also be pointed out that species totals may differ depending on the classificatory schema used; in some taxonomies, for example, animals that in this book are lumped together as subspecies are considered separate species (e.g., the various subspecies of Savanna Baboons, Flamingos, or Wapiti/Red Deer). This roster also excludes a wide variety of other cases in which the evidence for homosexual activities is not definitive, such as:

1. species in which homosexual activity is suspected (and sometimes included in comprehensive surveys of homosexual behavior, such as Dagg 1984) but in which the sex of participants has not yet been coin-firmed (e.g., one-horned rhinoceros [Laurie 1982:323], yellow-bellied marmot [Armitage 1962:327], South African cliff swallow [Earlé 1985:46], band-tailed barbfhroat hummingbird [Harms and Ahumada 1992], calliope hummingbird [Armstrong 1988], ringed Parakeet [Hardy 1964]).

2. bird species in which supernormal clutches have been documented without any direct evidence of same-sex pairs (e.g., numerous gulls and other bird species; see note 70, chapter 4).

3. same-sex trios or joint parenting arrangements with little or no conclusive evidence of courtship, sex, or pair-bonding between the like-sexed coparenis (e.g., bobolink [Bollinger et al. 1986], various ducks. grouse [cf. note 11, this chapter] ).