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RETROTRANSPOSONS. "It has been hypothesized that asexual organisms lack mechanisms sufficient to keep retrotransposons proliferation under control, explaining why retrotransposons are missing from ancient (i.e., evolutionarily stable) asexuals." https://lnkd.in/deZ8DED View in LinkedIn

MIXED MODES. "Most of these models found that there was an advantage for a low frequency of sexual reproduction over complete asexuality. Very few models exist explaining the evolution and maintenance of obligate sexuality in comparison with facultative sex. In fact, according to most models, organisms that engage in sexual reproduction only part of the time seem to have the best of both worlds." https://lnkd.in/es2qrc5 View in LinkedIn

SEX VS ASEXUALITY. "Many models explaining the advantage of sexual reproduction over asexuality have been proposed, including the purging of deleterious mutations, adaptation, host–parasite co-evolution, random genetic drift, and pluralistic models combining some or all of the above." http://onlinelibrary.wiley.com/doi/10.1002/ece3.1516/full View in LinkedIn

COMBINED ADVANTAGES. "In general, sex seems to allow superior responses to rapid challenges, both internal and external. Indeed, there is no consensus on a single major advantage for sex, and prevailing opinion is shifting toward a combination of advantages. That sex creates genetic variation, repairs DNA breaks, restores methylation patterns, and prevents accumulation of disadvantageous mutations is well accepted." https://lnkd.in/deZ8DED View in LinkedIn

"THE BENEFITS of eukaryotic meiotic sex are mostly discussed under the headings good, bad, and ugly: good, it generates genetic diversity in which rapid new combinations bring together beneficial mutations; bad, it purges the slow accumulation of slightly harmful mutations, i.e., it counters Muller’s ratchet; ugly, it is necessary for the arms race with rapidly changing parasites, the well-known Red Queen hypothesis." https://lnkd.in/deZ8DED View in LinkedIn

FRAGMENT FROM NATURE concludes this weekend on the theme of competition and resource allocation. At all levels of living creatures, from different species in ecosystems — from identical populations, from individual organs, from the cells within the body, from the ecosystem of organelles in cells, to the very genes — there is evidence of competition for key limited resources. These nested hierarchies of communities of living parts all appear to play out a dance between natural selection versus preferential resource allocation. View in LinkedIn

NEW CRITERION OF SELECTION. "We conclude that the least-time free energy consumption in respective surroundings, as the general criterion of natural selection, determines also sexual and asexual modes of reproduction." http://www.sciencedirect.com/science/article/pii/S0303264712001700 View in LinkedIn

"MEIOSIS is the type of cell division that gives rise to eggs and sperm." Versus mitosis which occurs during normal development and growth and does not alter the chromosome number. https://lnkd.in/dt3vnRH View in LinkedIn

ENERGY STRATEGY. "Parthenogenesis is a fast way to consume a rich repository of free energy, e.g., an ample stock of food with a large number of individuals, whereas sexual reproduction is a fast way to consume diverse and dispersed resources with a large variety of individuals." (Parthenogenesis is a type of asexual reproduction in which the offspring develops from unfertilized eggs). http://www.sciencedirect.com/science/article/pii/S0303264712001700 View in LinkedIn

DIPLOID FORM. “For most plants and all animals, the majority of life is spent in diploid form. During sexual reproduction, haploid gametes are formed via meiosis and then come together during fertilization.  Some simpler Eukaryota spend most of their life cycle in diploid form.” https://lnkd.in/dTisCwg View in LinkedIn