Males are therefore expected to mate with as many females as possible, while females are expected to be discriminating. However, given a simultaneous choice between two females of variable quality, it may be adaptive for a male to choose the higher quality female. A wide variety of animals tend to select mates based on judgment of particular qualities they possess which may indicate important information about a potential mate (Jones, 1992).
Previous studies have shown that often males use female size as a cue for assessing the size and quality of their clutch (Whiting & Bateman, 1999). In the lizard, Platysaurus broadleyi, previous studies have found that males often tend to select larger females, possibly for this reason (Fitzgerald,1982 ;Rostker, 1983 ;Whiting & Bateman, 1999). found that

Fecundity is an important aspect of female quality that may be evaluated by males (Trivers, 1972). Clutch size in P is fixed at two and Mou- broadleyi (van Wyk ton, 1996). However, egg size can reasonably be ex- pected to positively correlate with maternal body size, as has been reported for many lizard species with fixed clutch size (e.g., Andrews and Rand, 1974; Vitt,
1986; Doughty, 1997). This in turn may give larger offspring a competitive advantage (Lack, 1954; but see Sinervo et al., 1992). Based on this assumption, we tested the hypothesis that given a choice, males choose larger females.

Phenotypic factors such as maternal nutritional condition and allocation to developing embryos may also influence offspring survival (Olsson et al., 1996). Therefore, evolution of a male preference for large female size may have been driven by better offspring survival due to egg size, either through environmental or genetic sources of variation.

Alternatively, large female body size could correlate with some other maternal trait related to offspring growth and survival, regardless of egg size. A number of factors (both genetic and environmental) affect off-spring quality and hence, survival et al., 1992;

Conversely, male mate choice has received little attention, particularly for the Squamata (Olsson, 1993). Currently, male mate choice has been examined ex- perimentally for one lizard (Lacertaagilis; which is nonterritorial and mate guards), in which males pre- ferred large females (Olsson, 1993), and a snake,
Thamnophissirtalis parietalis (Aleksiuk and Gregory, 1974). Inferential evidence for male mate preference forlargefemalesexistsforanothermateguardingliz- ard, Eumeceslaticeps.In E. laticeps,clutch size is posi- tively correlated with female SVL, and males mate- guard larger females resulting in positive size-assor- tative mating (Cooper and Vitt, 1997). Two studies
(Fitzgerald, 1982; Rostker, 1983) have also provided evidence for a male preference for large females.
= males court multiple females in a short space of time,
Last, if larger offspring have a survival advantage, it would be adaptive for malestochooselargerfemales.MaleP.broadleyidid show a preference for larger females and this therefore best suits the fecundity model.
In general, male assessment of females entails vi- sual or chemical cues.

Society for the Study of Amphibians and Reptiles
Male Preference for Large Females in the Lizard Platysaurus broadleyi Author(s): Martin J. Whiting and Philip W. Bateman
Source: Journal of Herpetology, Vol. 33, No. 2 (Jun., 1999), pp. 309-312 Published by: Society for the Study of Amphibians and Reptiles
Stable URL: http://www.jstor.org/stable/1565730 . Accessed: 14/10/2014 22:52

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This, together with males’ preference for large females, might lead to size- assortative matings. We suggest that the quality and/or quantity of male pheromones could communicate to the female heritable male genetic quality (i.e. age) and thereby serve as the basis of adaptive female choice in lizards.

Behav Ecol Sociobiol (2003) 55:73–79 DOI 10.1007/s00265-003-0675-3
ORIGINAL ARTICLE
Pilar López · Pedro Aragón · JosØ Martín
Responses of female lizards, Lacerta monticola, to males chemical cues reflect their mating preference for older males

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Received: 29 April 2003 / Revised: 11 July 2003 / Accepted: 13 July 2003 / Published online: 2 September 2003 Springer-Verlag 2003

Large body size in female sand lizards is correlated with higher fecundity.
In choice experiments performed in the laboratory, male sand lizards preferred to court large females rather than small females. In addition, when there was little differ- ence in size between the females in the experiment, the males visited the two females

I investigatethe hypothesisthat males preferlarge, fecundfemalesby testingthe followingpredictions.(1) Inthelaboratory,malesinstagedchoiceexperiments should(a)preferlargefemales,and(b)spendmoretime choosing when femalesare closely size-matched.(2) In the field, (a) males should choose large femalesand (b) malechoiceshouldleadto assortativematingforbody size, as largedominantmalesmay excludesmallmales from largefemales.In the sand lizard,femalesdo not choose males (Olsson 1992b) and thereforeassortative matingcannotbe explainedby femalerejectionof small males.

To sum up, the experiment showed (1) that male sand lizards are selective in their choice of mate, and (2) that assessment of female size is more carefully performed when the size difference between the females is small.