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REDUCTIONISM FAILS. You cannot derive the function of organisms entirely from their molecules, despite a long history of thinking that you could. Does biology generate order from molecular disorder? Perhaps not, suggests Denis Nobel. Life is a process not fully programmed at the molecular level, generating order from disorder. Stochasticity is a key feature of gene expression. Non-genetic heterogeneity of cells in development is more than noise. https://lnkd.in/eBKWC7d View in LinkedIn

HEART OF DARKNESS. “It is only phenotypes that die, and thus selection on works on things it can see like phenotypes. The mechanism of natural selection is that some organisms survive better than others and reproduce more successfully, so you can only say that selection ‘sees’ what can live or die. Can a virus die? At whatever level an organism can live or die is where selection operates. This was Darwin’s theory of natural selection, and that can occur at any level. Richard Dawkins argues incorrectly that it is always genes that are selected for. It is a fundamental mistake.” https://lnkd.in/eBKWC7d View in LinkedIn

BLIND WATCHMAKER. “Was the watchmaker blind?” as Professor Richard Dawkins proposes, where evolution is random mutation followed by natural selection. Blind chance. Evolution has no foresight. Denis Nobel suggests a 21st century viewpoint, where evolution can be directional, organisms can harness stochasticity, with a one-eyed watchmaker responding epigenetically. Defied by unidirectional information flow. https://lnkd.in/eBKWC7d View in LinkedIn

HOTSPOTS. "The localisation of recombination events differs between species. In many species, recombination occurs in localised regions known as “recombination hotspots” of around 1-2kb in length, although some species (e.g., C. elegans and Drosophila) lack well-defined hotspots." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

SEX DIFFERENCES. "Meiotic drive systems are often entirely distinct between males and females and may be a primary cause of haploid selection." https://lnkd.in/e2tp_G5 View in LinkedIn

ANIMALS VS PLANTS. "Models point to a role of sex differences in selection during the haploid phase. Whilst a viable explanation in plants, there is little empirical support for this in animals, in which meiosis in females is only completed after fertilisation, so there is no true haploid phase, and the small number of expressed genes in sperm." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

UNEQUAL RECOMBINATION. "More intriguing are the quantitative differences between males and females, known as heterochiasmy, which are found in many taxa, but whose mechanistic and evolutionary drivers are not yet fully understood." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

EXTREME CASE. "In many species, cross-over rates and localisation differ between male and female meioses, and can differ in degree and direction even between closely related species. The most extreme case is achiasmy, an absence of recombination in one sex, nearly always the heterogametic sex. This may have evolved either as a side effect of selection to suppress recombination between the sex chromosomes." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

NON-RANDOM CROSSOVERS. "Crossover interference, where a cross-over in one position strongly reduces the likelihood of another cross-over occurring in the vicinity and/or on the same bivalent, meaning that the distribution of multiple cross-overs are non-random, is widespread" https://lnkd.in/e2tp_G5 View in LinkedIn

KEY EXCHANGE. "An ubiquitous feature of meiosis is the exchange of genetic material between homologous chromosomes." https://lnkd.in/e2tp_G5 View in LinkedIn