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REVERSE MEIOSIS. "In normal meiosis, homologous chromosomes are separated during meiotic division I whereas sister chromatids are separated during meiosis II. Why meiosis generally follows this order is unknown, but interestingly, meiosis can also take place in the reverse order in some species, including some flowering plants, mites, true bugs, and mealybugs." https://lnkd.in/e2tp_G5 View in LinkedIn

SCALING. “Here we present a systematic comparative mathematical analysis of the metabolic networks of 43 organisms representing all three domains of life. We show that, despite significant variation in their individual constituents and pathways, these metabolic networks have the same topological scaling properties and show striking similarities to the inherent organization of complex non-biological systems.” https://lnkd.in/em_2tJm View in LinkedIn

IMMENSE PROBLEM SOLVING. "Polyploidy with odd numbers of chromosome sets poses an even greater problem because aneuploid gametes are generally produced. However, there are some plant species where solutions to even this problem have evolved and odd-number polyploidy appears to persist stably." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

SONG OF DARWIN. "The more I study nature, the more I become impressed […] that the contrivances and beautiful adaptations [acquired through natural selection] transcend in an incomparable degree [those] which the most fertile imagination of the most imaginative man could suggest with unlimited time at his disposal." http://www.sciencedirect.com/science/article/pii/S0960982214003881 View in LinkedIn

TRANSITION MECHANISM. "Part of the answer seems to be a reduction in the number of COs, since multivalents can only form with at least two COs per chromosome. There is also mounting evidence for genes that have been selected to control pairing behaviour of chromosomes during meiosis, such as ph1 in hexaploid wheat and several candidate genes in polyploid." Arabidopsis." (CO = cross-overs). https://lnkd.in/e2tp_G5 View in LinkedIn

NECESSARY TRANSITIONS. "Given these detrimental effects, the existence of successful polyploid species and lineages indicates that natural selection can often promote transitions from multi- to bivalents that then segregate as in diploids. However, how such transitions are achieved at the molecular level remains a mystery." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

China’s moon mission to boldly go a step further View in LinkedIn

SO ENDS this consideration of where living things fit in the world of scale. The immensity of smallness on one hand, balances with the hugeness of immensity on the other. Life is sandwiched in between. Whether superorganisms such as bacteria and viruses add a few more orders of magnitude is as yet unknown. View in LinkedIn

SPACE BIOLOGY, driven by man’s thirst to explore other planets, is forcing us to consider the next series of scales. “Scientists observed that returning astronauts had grown taller and had substantially reduced bone and muscle mass.” They also have cognitive and immune problems. https://lnkd.in/dEPb-CN View in LinkedIn

PUT ANOTHER WAY. “On a logarithmic scale if the single cell life is considered to be at the zero point, Planck limit and Hubble horizon limit are equidistant.” https://lnkd.in/dfZFAM5 View in LinkedIn