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DOWN THE MIDDLE. "The only way of both reducing chromosome number and ensuring that gametes inherit a complete copy of the genome is to segregate maternal and paternal versions of each chromosome, known as homologous chromosomes, in opposite directions at the first of the two meiotic divisions." http://www.sciencedirect.com/science/article/pii/S0092867403000837 View in LinkedIn

PRECISE REDUCTION. "In reducing the chromosome number, it is not merely sufficient to end up, in a random manner, with a haploid number of chromosomes in the gamete. The haploid gametes produced by meiosis must contain one copy of each unique chromosome." https://lnkd.in/dd-eUTZ View in LinkedIn

"THE PURPOSE OF MEIOSIS is to generate haploid gametes from diploid cells. Meiosis, like mitosis, begins with the replication of DNA, thus producing a cell with four chromatids of each type of chromosome—two maternal and two paternal. These four chromatids have to be distributed to four different nuclei.” https://lnkd.in/dd-eUTZ View in LinkedIn

MEIOTIC REDUCTION. "A question of central importance to heredity in sexually reproducing eukaryotes is how haploid gametes are generated from diploid somatic cells. The answer lies in a specialized form of cell division during which the number of chromosomes is reduced. In 1905, Farmer and Moore termed this specialized form of cell division meiosis (derived from the Greek word, meaning “reduction”)." https://lnkd.in/dd-eUTZ View in LinkedIn

PLOIDY "is the number of sets of chromosomes found in a cell." https://genetics-notes.wikispaces.com/Ploidy View in LinkedIn

SEX BEGETS VARIATION. "Numerous studies across a range of organisms have convergently shown that the majority of variation in overall gene expression is explained by sex. These sex-biased genes have distinct evolutionary properties, namely they show faster rates of sequence and expression divergence, as well as rapid rates of turnover, broadly consistent with sexual selection." https://lnkd.in/dpjGKhi View in LinkedIn

FACTOID. "The effect of sexually antagonistic alleles is greater in long-adapted populations." https://lnkd.in/d4usB5Q View in LinkedIn

PAST HISTORY. "A population's evolutionary history may influence the effect of sexual selection." http://www.sciencedirect.com/science/article/pii/S0960982211013972 View in LinkedIn

FRAGMENT FROM NATURE focuses for the next two weekends in gene life cycles. Like water fleas and planets, genes also have life cycles of birth, middle age and death. Unlike the former two cases, genes may be resurrected into new functions and return to Go in the great game of Monopoly, all over again. We have tended to adopt our human time myopia, and imagine that our genomes are relatively fixed, except for mutations, but in the timeframes of genes, they are dynamic and constantly changing. Enjoy the new perspective, implicitly asking “quo vadis?” View in LinkedIn

WHERE QUESTIONS ALWAYS LEAD. "This uncertainty hinges on whether or not sexual and natural selection act in the same direction, and arises from another central problem in evolutionary biology; what maintains genetic variation in fitness?" https://lnkd.in/d4usB5Q View in LinkedIn