Figure 1.

Aphid performance on V. faba and L. purpureum. (a) Clones with ‘natural’ bacterial complement (n=8; open circles, secondary symbiont-free aphids; open triangles, aphids with H. defensa; open squares, aphids with R. insecticola); (b) clones cured of their natural secondary symbiont infections (n=9; filled triangles, aphids with H. defensa; filled squares, aphids with R. insecticola; open triangles, aphids cured of H. defensa; open squares, aphids cured of R. insecticola); (c) clones experimentally infected with secondary symbionts (n=9; filled triangles, aphids experimentally infected with H. defensa; filled squares, aphids experimentally infected with R. insecticola; open triangles, aphids lacking H. defensa; open squares, aphids lacking R. insecticola). Error bars are not displayed for clarity. Numbers in (b) and (c) indicate aphid clone numbers.