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Considerable interest has been given to the evaluation of male quality by females during mating (e.g., Bateson, 1983). For example, there has been debate among behavioral ecologists as to whether females can assess the "genetic qualities" of males per se, or whether females merely evaluate the quality or quantity of resources that different males sequester (Boake, 1986). In either case, Kodric-Brown and Brown (1984) suggested that females should seek "truth in advertising" by males: i.e., traits that "honestly advertise desirable attributes that can be passed on to both male and female offspring." The perceived ability of a male to obtain a high quality diet, in competition with other males, is one means by which a female might judge the male's ability to provide "good genes" (Boake, 1986) for her offspring or, simply, to provide high quality food resources for herself, her offspring, or both (Halliday, 1983). Walls et al. (1989) proposed what can be called the "sexy faeces hypothesis" to explain how female redbacked salamanders (Plethodon cinereus: Plethodontidae) associate with particular males. They found that gravid females distinguished faecal pellets of males that fed on highly nutritious prey (i.e., Isoptera) from faecal pellets of those same males that fed on prey of inferior quality (i.e., Hymenoptera). Such females preferred to remain in the immediate areas "marked" by the isopteran pellets. Walls et al. (1989) also showed that, in a natural forest habitat, male red-backed salamanders with termites in their territories (and in their stomachs) had significantly greater association with gravid females than did nearby males with ants in their territories (and in their stomachs). Walls et al. suggested that female red-backed salamanders use male faecal pellets as a reliable indication of male territorial quality, and on that basis females might determine with which male (or males) to mate. There are two major problems with the "sexy faeces hypothesis" as related by Walls et al. (1989). First, they did not carry their observations of male-female association through to actual courtship and insemination of females by their associated males. Indeed, Plethodon cinereus has seldom been induced to court under laboratory conditions, and such courtship is difficult to observe in natural habitats (but see Gergits s Epicrates and Carib ean vicariance theory. . ap. Mus. Zo l., Univ. Michigan 715: -68. , A. M. 1969. Squamate cloacal glands: Morl y, histology, and histochemistry. Unpubl. . . iss., Pen sylvania Sta e Univ. 147 pp. |
