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ANGIOSPERM EVOLUTION. "It is tempting to speculate that the first angiosperms were dioecious and that this state has then evolved into the hermaphrodites which dominate the present flora and which have 'reverted' to generate the unisexual species." https://lnkd.in/gb3zS32 View in LinkedIn

FEUDALISM DECLINES. “In the decades following the pandemic, Europe experienced significant economic, social, scientific, and religious changes. Increased wages empowered peasants, causing serfdom to disappear in many places, triggering the decline of manorialism. The demand for labor was so high it threatened manorial holdings. Serfs, no longer tied to one landlord, could easily leave for another who would hire them.” https://lnkd.in/gyBNmBb View in LinkedIn

FIRST ANGIOSPERM. "Recent sequencing analyses suggest strongly that Amborella trichopoda, an evergreen dioecious shrub endemic to New Caledonia, is the first branch of angiosperm evolution." https://lnkd.in/gb3zS32 View in LinkedIn

FAMILY TREE RECONSTRUCTIONS. "Many attempts have been made, using morphological and molecular systematics, to reconstruct the early evolutionary history of the 250 000 or so species of flowering plants." https://lnkd.in/gb3zS32 View in LinkedIn

"DISTYLY has probably arisen to promote pollen dispersal (and therefore outcrossing) and is often associated with self incompatibility. Specialization of one type for maleness and the other for femaleness may progress to full dioecy." https://lnkd.in/gb3zS32 View in LinkedIn

“HETEROSTYLY is a unique form of polymorphism and herkogamy in flowers. In a heterostylous species, two or three morphological types of flowers, termed "morphs", exist in the population. On each individual plant, all flowers share the same morph. The flower morphs differ in the lengths of the pistil and stamens, and these traits are not continuous.“ https://lnkd.in/dBgeGam View in LinkedIn

SEQUENCE DEGENERACY. "There is emerging evidence that plant sex chromosomes show some sequence degeneracy, as is the case in animal Y chromosomes, where the non-pairing segment of the Y chromosome largely lacks functional loci." https://lnkd.in/gb3zS32 View in LinkedIn

VIRAL SEQUENCES AND SEX CHROMOSOMES. "In Rumex acetosa, sex chromosome specific repeated sequences have been described and the sex chromosomes appear to contain large amounts of retroviral and viral related sequences." https://lnkd.in/gb3zS32 View in LinkedIn

PLOIDY EVENTS. "Although it is clear that the evolution of plant sex chromosomes is associated with large increases in the DNA amount, the reasons behind these increases and the types of sequence are not well understood." https://lnkd.in/gb3zS32 View in LinkedIn

INDEPENDENT BUT SIMILAR. "Sex-chromosomes in flowering plants have evolved independently but have a number of features in common. The X and Y chromosomes are always the largest chromosomes in the complement (and probably in the entire genus) and the Y chromosomes (or summed Y-multiples) are much larger than the X in all species except Humulus lupulus and Viscum." https://lnkd.in/gb3zS32 View in LinkedIn