Table 3.

Studies examining associations between the reproductive assurance benefit of selfing and factors thought to limit outcross pollen in nature

Species	Study*	Selfing = RA?†	Selfing variation§	Potential correlate of ↑ selfing?¶	References
Studies identifying an environmental correlate of RA
Aquilegia canadensis	CP	Yes	s	↓ Plant density	Herlihy and Eckert, 2004
Arenaria uniflora	MP	Yes‡	Flower size	↑ Heterospecific pollen	Fishman and Wyatt, 1999
Bulbine vagans	MP	Yes	R	Inclement weather	Vaughton and Ramsey, 2010
Campanula spp.	CP	Yes	s	↓ Pollinator visitation	Inouye et al., 1996
Clarkia xantiana	CP, CG	Yes	Herkogamy	↓ Pollinator abundance; ↓ plant density	Moeller and Geber, 2005; Moeller, 2006
Collinsia parviflora	CP, CG	Yes	R, flower size	↓ Pollinator visitation	Kennedy and Elle, 2008; Elle and Carney, 2003
Eichhornia paniculata	CP	Yes‡	s	↓ Plant density	Barrett et al., 1989; Husband and Barrett, 1991
Linanthus spp.	CP	Yes‡	SC	↑ Variation in pollen limitation	Goodwillie, 2001
Phyllodoce aleutica	CP	Yes	s	↓ Pollinator activity	Kameyama and Kudo, 2009
Paris quadrifolia	CP	Yes	R	↓ Plant density	Jacquemyn and Brys, 2008
Primula vulgaris	CP, CG	Yes‡	Heterostyly	↓ Pollinator visitation	Piper et al., 1986
Ranunculus reptans	CP	Unknown	SC	↓ Mate availability	Willi, 2009
Schizanthus spp.	MP	Yes	R	↑ Pollinator specialization	Perez et al., 2009
Studies not identifying an environmental correlate of RA
Aquilegia canadensis	CP	Yes	s	↓ Plant density range edges	Herlihy and Eckert, 2005; Eckert et al., 2009b
Arenaria uniflora	CP	Unknown	Flower size	↓ Pollinator visitation	Wyatt, 1986
Crepis sancta	CP	Unknown	s	Earlier successional stages	Cheptou et al., 2002
Datura stramonium	CP	Yes	R	↓ Plant density	van Kleunen et al., 2007
Eichhornia paniculata	CP	Unknown	Heterostyly	↓ Pollinator visitation	Husband and Barrett, 1992
Eritrichium nanum	CP	Unknown	s	↑ Altitude	Wirth et al., 2010
Gesnerieae spp.	CP	Yes	R	↑ Pollinator specialization	Marten-Rodriguez and Fenster, 2010
Helleborus foetidus	CP	Yes	R	↓ Pollinator visitation	Herrera et al., 2001
Leavenworthia alabamica	CG	Yes‡	SC	Range edges	Busch, 2005
Nicotiana glauca	CP	Yes	R	↓ Pollinator visitation	Schueller, 2004

* Studies involve either correlations among populations (CP), manipulations of pollination environment (MP) or common garden experiments (CG).

^† ‘Yes’ denotes that a study used floral emasculation in natural populations to test if selfing provides reproductive assurance.

^‡ In these cases, reproductive assurance is inferred because selfing plants produce more seed than closely related outcrossers

^§ Studies were included if they measured the selfing rate inferred with molecular markers (s), variation in self-compatibility (SC), key indicators of selfing, or the reproductive assurance benefit of selfing R = 1 – (seed seet_emasculated/seed set_intact).

^¶ Factors that were investigated to see if they correlate positively (↑) or negatively (↓) with an increase in selfing.