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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

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‘My job is to clean up the environment. China really wants to do that’ https://www.theguardian.com/environment/2017/sep/10/my-job-is-to-clean-up-the-environment-china-really-wants-to-do-that?CMP=Share_iOSApp_Other View in LinkedIn

SO ENDS this foray into hybrids and speciation. Tullimonstrum (the Tully Monster) has been a taxonomic conundrum for a long time, seemingly cobbled together from various taxa and without comparator, and is fossil proof of the extreme of speciation weirdness. It will not be the last such example. https://lnkd.in/dm8QrFv View in LinkedIn

OTHER MECHANISMS. "Admixture can simultaneously bring together many new combinations of alleles, generating multilocus novelties that might never have appeared via gradual accumulation of new mutations in a single population. Gene exchange is not the sole, nor even necessarily most likely, source of evolutionary novelty, but is perhaps the most likely mechanism of sudden, population level change. Transgressive segregation might be just the mechanism to make more monsters hopeful." http://link.springer.com/article/10.1007/s11692-012-9209-0 View in LinkedIn