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RECOMBINATIONAL DOMINANCE. "Admixed populations will also produce many similar recombinant phenotypes at the same time, increasing the probability that recombinant “hopeful monsters” will establish true-breeding evolutionary lineages. Recombination is not the only (or even most common) process generating evolutionary novelty, but might be the most credible mechanism for sudden appearance of new forms." http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn

HOPEFUL MONSTERS. "The origin of novelty is a critical subject for evolutionary biologists. Early geneticists speculated about the sudden appearance of new species via special macromutations, epitomized by Goldschmidt’s infamous “hopeful monster”." http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn

MENDELIAN SPECTRUM. "Recombination has always been recognized as an important source of variation; whether such variation is perceived as profound or “monstrous” is a matter of degree rather than kind." http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn

EVOLUTION BY SALTATIONS. "Suggestions to the contrary (to gradualism) were met with ridicule: geneticist Richard Goldschmidt, in 1940, envisioned subtle developmental mechanisms producing great leaps of adaptation, but his use of the phrase "hopeful monsters" was misrepresented as extreme saltationism (perfection in one jump), and equated with belief in miracles." https://lnkd.in/dAC2mFa View in LinkedIn

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