Figure 5.

Mean caste‐ratio (±SE) in snails infected by Philophthalmus sp. 12 weeks after shell manipulation (three treatments: undrilled, patched or drilled) in host individuals harboring single (Philophthalmus sp. only) and double (Philophthalmus sp. and Maritrema novaezealandense) infections. Caste‐ratio is the number of soldier morph Philophthalmus sp. rediae divided by the number of reproductive morphs within an individual snail host. Horizontal lines indicate significant differences between particular groups (α = 0.05). Numbers given inside bars are sample sizes; note that no drilled snail harboring a double infection survived the twelve‐week experiment