SUMMARY Sex ratios in 35 inflorescence and plant counts of perennial, sexually dimorphic Umbelliferae vary from 0·96 to 87·33 times as many males as females. The ranges of ratios are similar

in dioecious and gynodioecious populations. In 10 populations in which both the inflorescences and plants were counted, the male/female ratios are approximately one in populations in which

the plants produce only one inflorescence per year and increase as the average number of inflorescences increases. The interpretation offered is that the sex ratio is approximately one until

reproduction begins, and in subsequent years increasingly male-biased ratios develop because sexual reproduction utilises more of the available resources of females than of males. Following

separate competition among males and among females during sexual reproduction. The seed set and fitness of total populations may actually decrease with the development of marked male

preponderance. SIMILAR CONTENT BEING VIEWED BY OTHERS UNEQUAL ALLOCATION BETWEEN MALE VERSUS FEMALE REPRODUCTION CANNOT EXPLAIN EXTREME VEGETATIVE DIMORPHISM IN _AULAX_ SPECIES (CAPE

PROTEACEAE) Article Open access 26 January 2022 SEX-BIASED GENES AND METABOLITES EXPLAIN MORPHOLOGICALLY SEXUAL DIMORPHISM AND REPRODUCTIVE COSTS IN SALIX PARAPLESIA CATKINS Article Open

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Download references AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Botany Department, University of Canterbury, Christchurch, New Zealand David G Lloyd Authors * David G Lloyd View author

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