the green dragon, which can change its sex on a yearly basis. A. dracontiums sex is also dependent on size: the smaller flowers are male while the larger flowers are both male and female. Typically in Arisaema species, small flowers only contain stamens, meaning they are males. Larger flowers can contain both stamen and pistils or only pistils, meaning they can be either hermaphrodites or strictly female. Overall, Arisaemas are changing their sex as they grow larger, maximizing the overall fitness for that particular environment. Striped maple (Acer pensylvanicum) Striped maple trees (Acer pensylvanicum) are sequential hermaphrodites as they are known to have the ability to change sex. Starting in 2014, a case study showed that over a four year time span 54% of striped maple trees developed a different sex. Scientists removed branches from striped maple trees to research the cause of their sequential hermaphroditism. It was found that the branches changed to either female or female and male as a response to being damaged by being cut off the tree. Researchers concur that when the striped maple experiences damage or is sick, this will trigger a sex change to either female or female and male. This could be because the striped maple would need to bloom as quickly as possible, producing offspring before it ultimately dies from damage or sickness. Dichogamy in flowering plants In the context of the plant sexuality of flowering plants (angiosperms), there are two forms of dichogamy: protogyny—female function precedes male function—and protandry'''—male function precedes female function. Examples include in Asteraceae, bisexual tubular (disks) florets are usually protandrous. Whereas in Acacia and Banksia flowers are protogynous, with the style of the female flower elongating, then in the male phase shedding pollen. Evolution Historically, dichogamy has been regarded as a mechanism for reducing inbreeding. However, a survey of the angiosperms found that self-incompatible (SI) plants, which are incapable of inbreeding, were as likely to be dichogamous as were self-compatible (SC) plants. This finding led to a reinterpretation of dichogamy as a more general mechanism for reducing the impact of pollen-pistil interference on pollen import and export. Unlike the inbreeding avoidance hypothesis, which focused on female function, this interference-avoidance hypothesis considers both reproductive functions. Mechanism In many hermaphroditic species, the close physical proximity of anthers and stigma makes interference unavoidable, either within a flower or between flowers on an inflorescence. Within-flower interference, which occurs when either