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RISE OF THE HOPEFUL MONSTERS. "But through fish in the murky depths of a British Columbia lake and through bacteria in the flasks of a Michigan lab, the monsters have returned. Experimental evidence has shown that individual genetic changes can have vast effects on an organism without dooming it to the evolutionary rubbish heap." https://lnkd.in/dAC2mFa View in LinkedIn

GRADUALISTIC EVOLUTION. "Since the origin of evolutionary science, biologists have insisted that adaptation is an achingly slow process. ' Natura non facit saltum ' (nature does not take leaps) was a favourite incantation of Charles Darwin. As the combined power of genetic mutation and natural selection became better appreciated in the 1930s and 1940s, theorists solidified a gradualist doctrine: adaptation must rely on innumerable genetic changes, each with effects so small that any attempt to catch them experimentally was considered futile." https://lnkd.in/dAC2mFa View in LinkedIn

MONSTER SALTATIONS. "This small selection of cases serves to illustrate sudden appearance of profound differences between parents and hybrid offspring reminiscent of Goldschmidt’s hopeful monsters." https://lnkd.in/dDz5VYD View in LinkedIn

FRAGMENT FROM NATURE continues the theme from last weekend of hybrids, but strays into the theme of gradual versus sudden leaps of evolution and the lovely concept of hopeful monsters. Hybridization as a source of genetic novelty and new species has long fascinated biologists, but many natural hybrids are sterile, making them ‘sports of transmutations’ (Wordsworth). Enjoy this partly historical view of the subject. View in LinkedIn

EXAMPLES OF HYBRID FITNESS. "A few examples of new phenotypes inferred to arise from hybridization include: extreme size of tiger x lion F1 hybrids; unique shapes and colors of hybrid orchids; ability of recombinant sunflowers to thrive in extreme habits; specialization on a novel host plant in lonicera flies; and expression of novel gene transcripts (including new exons) via alternative splicing in hybrid poplars." https://lnkd.in/dDz5VYD View in LinkedIn

GREATER HYBRID FITNESS. "Often, transgressive hybrids have higher fitness in novel environments, increasing the likelihood of divergence from parental populations." http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn

NEW POSSIBILITIES ALLOWED. "Genetic recombination in hybrids can produce transgressive phenotypes, “monstrous” phenotypes beyond the range of parental populations. Transgressive phenotypes can be products of epistatic interactions or additive effects of multiple recombined loci." http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn

CREDIBLE HYBRID SPECIATION. "Recent empirical and theoretical research on hybrid speciation might have revived the hopeful monster in a new, more credible form. Recombination of parental chromosomes in the F2 and later generations during hybridization can generate genotypes that express phenotypes outside the normal range of variation observed in either parental gene pool, a phenomenon termed “transgressive segregation”.” http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn

THE GENETIC CONFIRMATION. "Modern evolutionary theory and empirical research in genetics have consistently reaffirmed the ability of conventional population genetics to explain the origin of new species and phenotypes, and simultaneously exposed flaws in the alternatives." http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn

NO SUSPENDED DISBELIEF. "A hopeful monster is an individual phenotypically discontinuous from the range of phenotypes of its population, and whose hopes of establishing a new lineage lie in finding a novel niche for which its monstrosity happens to be preadapted. Such a mechanism of speciation was criticized early for being so improbable as to “overtax one’s credulity” because of the rarity of the initial mutation of large effect, and the resulting improbability of finding an equally monstrous mate." http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn