Re: is there a difference in when estimating between females and males

I am assuming that you are referring to estimating physical size and 
volume which is a visuospatial ability.

Male-female differences in tasks involving spatial processing have been 
attributed to gender-specific specialization of the two hemispheres of 
the  brain [Rasmjou, Hausmann and Güntürkün 1999]. Men have been 
called ‘right-brained’ as the right hemisphere is the one that usually 
deals with visuo-spatial tasks. Women who tend to be quicker at tasks 
involving language processing have been called ‘left-brained’. It has not 
been established as to whether this specialization of the two hemispheres 
occurs as a result of  genetic factors, sex hormones or environmental and 
cultural mechanisms. 

One theory that explains the gender differences in spatial abilities is 
Silverman and Eals’ [1992] hunter-gatherer theory of the origin of sex-
specific spatial attributes. This view holds that men and women have 
different cognitive abilities appropriate to their sex roles in their 
prehistoric lifestyles. Prehistoric females (i.e. gatherers) who had to 
forage for food and keep track of objects, locations and landmarks near 
their homes were more successful at acquiring resources for bearing and 
raising offspring. Males (i.e. hunters) who were better able to travel in 
unfamiliar territory, estimate distance, and navigate with a ‘bird’s eye 
view’ orientation were more successful at hunting, competing with
other males, finding mates, and having children.

Thus these male-female cognitive differences arose through the process of 
evolutionary selection. In support of this theory, Dabbs et al [1998] 
demonstrated that females outperform men on spatial tasks such as 
remembering the location of objects in the environment and men have 
better ‘mental rotation’ spatial abilities than women. Additionally 
researchers since the 1970s have found that men typically outperform women 
at spatial tasks that involve manipulating objects in space [Maccoby and 
Jacklin 1974].

References:

DABBS, J.M., CHANG, E.-L., STRONG, R.A. AND MILUN, R. 1998. Spatial 
ability, navigation strategy, and
geographic knowledge among men and women. Evolution and Human Behavior 19, 
89-98.

MACCOBY, E.E. AND JACKLIN, C.N. 1974. The Psychology of Sex Differences. 
Stanford, CA: Stanford University Press.

RASMJOU, S., HAUSMANN, M. AND GÜNTÜRKÜN, O. 1999. Hemispheric dominance 
and gender in the perception of an illusion. Neuropsychologia 37, 1041-
1047.

SILVERMAN, I. AND EALS, M. 1992. Sex differences in spatial abilities: 
Evolutionary theory and data. In The Adapted Mind: Evolutionary Psychology 
and the Generation of Culture, J.H. BARKOW, L. COSMIDES and J.TOOBY, Eds. 
New York: Oxford Press, 531-549.

Please note I have taken this information from a paper by Geoffrey Hubona 
which can be found at http://www.cis.gsu.edu/~ghubona/gender/hubona.pdf