Month: September 2022

DEAD END REFUTED. "Here, we present a new data set that was obtained by searching the phylogenetic literature on more than 600 completely dioecious angiosperm genera and identifying 115 sister clade pairs for which dioecy is likely to be derived (including > 50% of the dioecious species). Applying the new sister clade test to this new dataset, we confirm the preliminary result that dioecy is associated with an increased diversification rate, a result that does not support the idea that dioecy is an evolutionary dead end in angiosperms." https://lnkd.in/gGPGHvb View in LinkedIn

NUANCED EXPLANATION. "The traits usually associated with dioecy, that is, an arborescent growth form, abiotic pollination, fleshy fruits or a tropical distribution, do not influence the diversification rate. Rather than a low diversification rate, the observed species richness patterns of dioecious clades seem to be better explained by a low transition rate to dioecy and frequent losses." https://lnkd.in/gGPGHvb View in LinkedIn

TIME. "Our results also show that contrasting forces act on the genomes of dioecious plants, and suggest that some time is required before the genome of such plants bears the footprints of dioecy." https://lnkd.in/gRVz_Qd View in LinkedIn

EPIGENETIC TRAP. "Inherited epigenetic variation could also be maladaptive, becoming an epigenetic trap. This is because environmental sex determination can alter sex ratios by increasing the survival of one of the sexes at the expense of negative fitness consequences for the other, which could lead not only to the collapse of natural populations, but also have an impact in farmed animal and plant species."" "DOI: 10.1002/bies.201600058 View in LinkedIn

SEXUAL SELECTION. Darwin "proposed that sexual selection resulting from variation among individuals in mating success could explain the evolution of sexual dimorphism, and distinguished two fundamentally different types: intrasexual competition among individuals of one sex for mates, and intersexual selection or ‘mate choice’ resulting from the preferences of one sex for traits of the other." https://lnkd.in/ge7JD6J View in LinkedIn

AVOIDING INBREEDING. "The evolution of unisexual systems has often been related to the fact that outcrossing avoids the consequences of inbreeding depression." https://lnkd.in/g_fheyF View in LinkedIn

CHARACTERISTICS. "Dioecy has been correlated with plant spatial distribution, tropical floras, oceanic islands, and oligotrophic environments, and since Darwin (1877), resource allocation has been suggested as a causal factor in the evolution and maintenance of dioecy." https://lnkd.in/g_fheyF View in LinkedIn

DIOECIOUS TRAITS. "Recent large-scale molecular phylogenetic analyses confirm some of the correlations between dioecy and ecological traits and highlight the diversification of dioecious lineages associated with ecological features" such as woodiness, climber habit, and fleshy fruits. https://lnkd.in/g_fheyF View in LinkedIn

OVERLOOKED. "Darwin (1871) largely neglected the possibility that sexual selection might also operate in plants. This may have been because of their non-sentient habit, primarily hermaphroditic sexual condition, and less conspicuous sexual dimorphism in dioecious species." https://lnkd.in/ge7JD6J View in LinkedIn

UNISEXUALITY IN PLANTS. "Unisexual plant species and their mixed forms appear to be distributed throughout the flowering plant families (around three quarters of families include dioecious species) suggesting independent evolutionary events. However, the incidence of unisexuality is not evenly spread throughout the plant kingdom." https://lnkd.in/gb3zS32 View in LinkedIn