Biology Reference
In-Depth Information
Female first (protogynous species)
25
20
15
10
5
0
0-0.1
0.11-0.2
0.21-0.3
0.31-0.40.41-0.50.51-0.6
0.61-0.7
0.71-0.8
0.81-0.9
0.91-1.0
Sex ratio (proportion males)
Male first (protandrous species)
25
20
15
10
5
0
0-0.1 0.11-0.2
0.21-0.3
0.31-0.4 0.41-0.5 0.51-0.6
0.61-0.7
0.71-0.8
0.81-0.9
0.91-1.0
Sex ratio (proportion males)
Fig. B10.4.2
The distribution of population sex ratios in sex changing species that
are either (a) female (protogynous) or (b) male (protandrous) first. The population sex
ratio tends to be biased towards the first sex. From Allsop and West (2004).
1.5
Male
Female
1.0
0.5
0.0
-0.5
Non-sex-change
Female-first
sex-changer
Reproductive mode
Fig. B10.4.3
The correlation between gametic investment and the occurrence of sex
change. Species with female first sex change had relatively similar size female gonads, but
smaller testes, than species where sex change did not occur. From Molloy
et al
. (2007).
