Figure 2

Relationships between the head shape (width relative to length) of a turtle-headed sea snake Emydocephalus annulatus, and (a) the snake’s growth rate (increment in snout-vent length [SVL] per year), (b) reproductive state (gravid or not) and (c) litter size. Relative head-width values are combined into categories to facilitate visualisation of trends; each interval of relative head length shows mean value and associated standard error for the relevant variable.