Size dimorphism, sexual

Kappeler, P. M., 1990b, The evolution of sexual size dimorphism in prosimian primates. Am. J. Primatol 21 201-214. 

Sexual dimorphism—The occurrence of marked differences in coloration, size, or shape between males and females of the same species. 

The cebid monkeys vary in size from the squirrel monkey (S. sciureus) with a body length of 10 in (25 cm) plus a 15 in (38 cm) tail, and a weight of about 1.5 lbs (0.68 kg), to the woolly spider monkey, or muriqui, which has a body length of 18 in (46 cm), plus a 30 in (75 cm) tail, and weighs about 35 lb (17.5 kg). The males and females of most species of cebid monkeys are approximately the same size, but the two sexes often have different colorings, a phenomenon known as sexual dimorphism. 

Hailey Have you given up the sexual dimorphism in g too easily The indirect evidence is that the single, best established sex difference in the brain is brain size, even after controlling for body size. Do you know Jackson s data He argues that part of the reason why IQ tests don t show sex difference is because the items that show sex difference are discarded. He presented data showing a difference of a few points when this is corrected for (D. N. Jackson, unpublished paper, 1st Int Behav Dev Symp, 25-27 May 1995). Finally, it is well established that variation in IQ is higher for men than for women. 

Even in those crustacean species where visible morphological sex differences in the chemosensory sensilla are small or imperceptible, variations of aesthetasc structure, size and number, sensory cell morphology, and spatial arrangement can still occur. Any such sexual dimorphism could help enlighten the sex-specific role of these chemosensory structures in, for example, reproductive behaviors. 

Sexual dimorphism of both the size of the preorbital fossa and the development of the preorbital sac have been observed among several cervids and bovids (Schaffer, 1940 Chapman and Chapman, 1982). Comparatively little is known about the histological nature of this difference, especially its effect upon the glandular epithelial lining of the fossa (Schaffer, 1940 Lincoln, 1971 Quay and MUller-Schwarze, 1971 Mossing and Kailquist, 1981). There have been no reports of sexual dimorphism in deer Harderian glands. 

In the common marmoset, for example, large sebaceous and apocrine glands are located mainly in the skin of the external genitalia, while the suprapubic area does not show morphologically differentiated glandular fields. There is no sexual dimorphism in the size of the glands (Sutcliffe and Poole, 1978). In the saddle-back tamarin, on the other... 

---