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SUCCESSION RISKS. "When old sex chromosomes self-destruct, a new sex gene and sex chromosomes may take over. This is fraught with peril because the interaction of old and new systems of sex determination is likely to cause severe infertility in hybrids." https://lnkd.in/ehjz378 View in LinkedIn

CO-SEXUAL FORMS. "First, dioecy in flowering plants seems often to have evolved from either hermaphroditism or monoecy, or, using the combined term, from co-sexuality. It follows directly that, during the evolution of dioecy, either females or males must first have arisen, and become established in the population (creating a situation with both co-sexuals and unisexuals, either gynodioecy or androdioecy), and then mutations must have spread among the co-sexuals, making them become the complementary unisexual form." https://lnkd.in/exrSaeb View in LinkedIn

GENE DEGRADATION. "The acquisition of a sex factor on one member of the pair is the kiss of death for that chromosome, and it degrades quickly. This explains why only a few active genes remain on the human Y and the bird W." https://lnkd.in/ehjz378 View in LinkedIn

TWO SUPPRESSIONS. "Dioecy in flowering plants must often have evolved through at least two mutations, a male-sterility mutation (creating females) and one or more female-sterility mutations (creating males)." https://lnkd.in/exrSaeb View in LinkedIn

Civil servants bordering on clueless over Brexit. A brilliant piece of writing. View in LinkedIn

HERMAPHRODITE COMPROMISE. "If this idea is correct, then changing from being hermaphrodite to becoming purely female or male ought to trigger a burst of adaptation, as females optimize their female functions, and males optimize their male functions." https://lnkd.in/exrSaeb View in LinkedIn

STRANGE EVOLUTION. "Sex chromosomes are really weird because of the way they evolved. They start off as ordinary chromosomes, known as autosomes. A new sex gene arises on one member of the pair, defining either a male-determining Y as in humans or a female-determining W as in birds." https://lnkd.in/ehjz378 View in LinkedIn

The Earth may not be flat, but it just might be doomed https://www.theguardian.com/commentisfree/2017/nov/19/the-earth-may-not-be-flat-but-it-is-possibly-doomed-fake-news?CMP=Share_iOSApp_Other View in LinkedIn

BRANCH IN THE TREE. "I propose that drastic sex chromosome changes could have played a direct role in separating our lineage (placental mammals), first from the egg-laying monotremes, then from marsupials." https://lnkd.in/ehjz378 View in LinkedIn

FIRST AND SECOND MAJOR UPHEAVAL. "The first corresponded to the divergence of monotreme mammals (platypus and echidna) from the rest, and the second to the divergence of marsupials from placental mammals (including humans)." https://lnkd.in/ehjz378 View in LinkedIn