Tuesday, February 19, 2019

What a biologist wrote about Idiot America's stupid fucking assholes.

"For all of those who do see the overwhelming evidence of natural selection and life's descent from ancestors, and the immense span of time over which the story of life unfolded, it is, to put it mildly, baffling how so many still do not. It is absolutely astonishing and often infuriating that some take it so far as to deny the immense foundation of evidence and to slander all the human achievement that foundation represents."
-- The Making of the Fittest: DNA and the Ultimate Forensic Evolution by Sean B. Carroll

Wikipedia:

Sean B. Carroll (born September 17, 1960) is an American evolutionary developmental biologist, author, educator and executive producer. He is the Allan Wilson Professor of Molecular Biology and Genetics at the University of Wisconsin–Madison. His studies focus on the evolution of cis-regulatory elements in the regulation of gene expression in the context of biological development, using Drosophila as a model system. He is a member of the National Academy of Sciences, of the American Philosophical Society (2007),[1] of the American Academy of Arts and Sciences and the American Association for Advancement of Science, as well as a Howard Hughes Medical Institute investigator.

Wikipedia:

Evolutionary developmental biology

Evolutionary developmental biology (informally, evo-devo) is a field of biological research that compares the developmental processes of different organisms to infer the ancestral relationships between them and how developmental processes evolved.

The field grew from 19th-century beginnings, where embryology faced a mystery: zoologistsdid not know how embryonic development was controlled at the molecular level. Charles Darwin noted that having similar embryos implied common ancestry, but little progress was made until the 1970s. Then, recombinant DNA technology at last brought embryology together with molecular genetics. A key early discovery was of homeotic genes that regulate development in a wide range of eukaryotes.

The field is characterised by some key concepts, which took evolutionary biologists by surprise. One is deep homology, the finding that dissimilar organs such as the eyes of insects, vertebrates and cephalopod molluscs, long thought to have evolved separately, are controlled by similar genes such as pax-6, from the evo-devo gene toolkit. These genes are ancient, being highly conserved among phyla; they generate the patterns in time and space which shape the embryo, and ultimately form the body plan of the organism. Another is that species do not differ much in their structural genes, such as those coding for enzymes; what does differ is the way that gene expression is regulated by the toolkit genes. These genes are reused, unchanged, many times in different parts of the embryo and at different stages of development, forming a complex cascade of control, switching other regulatory genes as well as structural genes on and off in a precise pattern. This multiple pleiotropic reuse explains why these genes are highly conserved, as any change would have many adverse consequences which natural selection would oppose.

New morphological features and ultimately new species are produced by variations in the toolkit, either when genes are expressed in a new pattern, or when toolkit genes acquire additional functions. Another possibility is the Neo-Lamarckian theory that epigenetic changes are later consolidated at gene level, something that may have been important early in the history of multicellular life.

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