Fig. 4.

Proportion of developing seeds with a chalazal haustorium 3, 4, 5, and 6 d after pollination (DAP) from intra‐ and interspecific crosses among Mimulus caespitosa (C), Mimulus tilingii (T), and Mimulus guttatus (G). Numbers in bars represent the total number of developing seeds scored for a chalazal haustorium, with a subset of seeds dissected from 1 to 2 fruits per cross per DAP. Seeds were only scored and imaged if they contained a visible embryo. The green color represents the proportion of seeds with a chalazal haustorium, and the yellow color represents the proportion of seeds without a chalazal haustorium. At days 3 and 4, chalazal haustorium presence was scored after dissecting developing seeds from whole ovules and clearing them with Hoyer's solution. At days 5 and 6, chalazal haustorium presence was scored on a subset of seeds from whole‐fruit histological sections. (a) Along the diagonal are the intraspecific crosses (C×C, T×T, and G×G), below the diagonal are maternal‐excess crosses (T×C, G×T, and G×C; maternal parent always listed first), and above the diagonal are paternal‐excess crosses (C×T, T×G, and C×G). (b) In the T_4x ×G cross, the ‘4x’ subscript denotes a synthetic tetraploid M. tilingii maternal parent. The ‘4–2’ above the bars further represents the cross between two ploidy levels, with a tetraploid maternal parent and diploid paternal parent.