Table 1.
Direct or indirect evidence for GMMC and potential evolutionary implications of the process. SC = sperm competition; + = supporting GMMC; − = no support for GMMC; I = internally fertilizing species; E = externally fertilizing species.
| mediating factor | mechanism | outcome | species | implications | GMMC | refs. |
|---|---|---|---|---|---|---|
| female reproductive tract secretions | ||||||
| soluble oviduct proteins | selective sperm activation | sperm selection? | Sus scrofa (I) | unknown | + | [34] |
| ovarian fluid | selective sperm motility stimulation | fertilization bias | Poecilia reticulata (I) | inbreeding avoidance | + | [46] |
| ovarian fluid | selective sperm motility stimulation | fertilization bias | Oncorhynchus tshawytscha (E) | incompatibility avoidance | + | [49–51] |
| ovarian fluid | general sperm motility stimulation | fertilization bias | Symphodus ocellatus (E) | directional selection | + | [48] |
| ovarian fluid | selective sperm motility stimulation | no fertilization bias | Oncorhynchus tshawytscha (E) | — | − | [47] |
| ovarian fluid | selective sperm motility stimulation | unknown | Salvelinus alpinus (E) | unknown | (+) | [52] |
| ovarian fluid | selective sperm motility stimulation | unknown | Oncorhynchus mykiss (E) | unknown | (+) | [53] |
| ovarian fluid | selective sperm motility stimulation | unknown | Oncorhynchus tshawytscha (E) | unknown | (+) | [54] |
| ovarian fluid | no selective sperm motility stimulation | unknown | Salvelinus namaycush (E) | — | (−) | [55] |
| egg-derived soluble factors | ||||||
| sperm chemoattractants | differential sperm chemotaxis success | fertilization bias (no SC) | Mytilus galloprovincialis (E) | incompatibility avoidance | + | [11,32] |
| sperm chemoattractants | differential sperm chemotaxis success | fertilization bias (SC situation) | Mytilus galloprovincialis (E) | incompatibility avoidance | + | [12] |
| non-soluble factors/gene-based gamete interactions | ||||||
| sperm surface protein (bindin) | unknown | assortative fertilization | Strongylocentrotus purpuratus (E) | incompatibility avoidance | + | [56] |
| MHC-dependent fertilization bias | unknown | fertilization bias | Salmo salar (E) | hybridization avoidance | + | [57] |
| sperm surface glycans | differential female immune response against sperm | reproductive incompatibility | Mouse (I) | incompatibility avoidance | + | [58] |
| sperm surface glycans | differential effect of soluble egg factors on sperm surface | sperm Ca2+ influx | Mytilus galloprovincialis (E) | incompatibility avoidance | (+) | [20] |