Image: Pollen competition in style: Effects of pollen size on siring success in the hermaphroditic common morning glory, Ipomoea purpurea Britnie McCallum and Shu-Mei Chang Am. J. Bot. 2016; 103:460-470 doi:10.3732/ajb.1500211 http://www.amjbot.org/content/103/3/460.abstract