Production of male flowers does not decrease with plant size in insect-pollinated Sagittaria trifolia, contrary to predictions of size-dependent sex allocation Reproductive allocation of three sympatric Comastoma(Gentianaceae)species Influence of Altitude on Reproductive Traits and Resource Allocation of Species of Ranunculaceae at East Qinghai Tibetan Plateu Size-dependent reproductive allocation of Gentianopsis paludosa in different habitats of the Qinghai-Tibetan Plateau Increased Maleness at Flowering Stage and Femaleness at Fruiting Stage with Size in an Andromonoecious Perennial, Veratrum nigrum Variation of reproductive allocation along elevations in Saussurea stella on East Qinghai-Xizang Plateau