Month: September 2022

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

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

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

REPEAT EVOLUTIONS. "Dioecy is considered by Charlesworth and Guttman (1999) to have evolved more than 100 times to account for the 160 plant families which include dioecious species." https://lnkd.in/gb3zS32 View in LinkedIn

LIMITING RECOMBINATION PAIRS. "In a small number of plant species the transition from hermaphroditism has been followed by the evolution of sex chromosomes, which presumably have evolved as a consequences of the need to limit recombination between the different sex determining genes." https://lnkd.in/gb3zS32 View in LinkedIn

PLANT SEX CHROMOSOMES. "Although sex chromosomes have been claimed for nearly a hundred plant species, the number of authenticated sex chromosome systems is at least an order of magnitude smaller." https://lnkd.in/gb3zS32 View in LinkedIn

RECENT ADDITION. "Plant sex chromosomes are probably of relatively recent origin, in contrast to the situation in animals, and thus afford the opportunity of investigating recent chromosome evolution." https://lnkd.in/gb3zS32 View in LinkedIn

PLANT SEX GENES. "Although sex chromosomes in flowering plants are rare, plants have evolved systems which are analogous to the main chromosomally-based systems in animals. For example, the Silene species have an active Y system similar to that in mammals where the Y chromosome acts as a maleness enhancer as well as suppressing the gynoecium." https://lnkd.in/gb3zS32 View in LinkedIn

ACTUAL NUMBER. "Differentiated sex chromosomes have been established clearly in only six families, representing about eight species and two major species groups." https://lnkd.in/gb3zS32 View in LinkedIn

INTERMEDIATE SYSTEM. "In Rumex hastatulus, which evolved a sex chromosome system independently of R. acetosa, both X and Y chromosomes are involved in an intermediate system." https://lnkd.in/gb3zS32 View in LinkedIn