The efficacy of selection depends on the effective population

What are the fundamentals of evolutionary biology

canada goose black friday sale Dan Graur, who is Professor of canada goose outlet black friday sale Biology and Biochemistry at the University of Houston, describes himself on Twtter as Very Angry Evolutionary Biologist, a Very Angry Liberal, and an Even Angrier Art Lover His Tumblr says he a very low threshold for hooey, hype, hypocrisy, postmodernism, bad statistics, ignorance of population genetics and evolutionary biology masquerading canada goose discount uk as omics, and hatred of any kind. yesterday he tweted a link to a document containing canada goose parka outlet uk what he called of evolutionary biology in 12 paragraphs, 237 words and 1,318 characters Here they are for your delectation. I made some comments at the end feel free to chip in (you too, Dan!). canada goose black friday sale

canada goose coats 7. The fate of mutations that do not affect fitness is determined by random canada goose outlet washington dc genetic drift; that of mutations that do affect fitness by the combination of selection and random genetic drift. canada goose coats

8. Evolution occurs at the population level; individuals do not evolve. An individual can only make an evolutionary contribution by producing offspring or canada goose outlet shop dying childless.

Canada Goose Coats On Sale 9. The efficacy of selection depends on the effective population size, an historical construct that is different from the census population size, which is a snapshot of the present. Canada Goose Coats On Sale

Canada Goose Outlet 10. Evolution cannot create something out of nothing; there is no true novelty in evolution. Canada Goose Outlet

uk canada goose 11. Evolution does not give rise to «intelligently designed» perfection. From an engineering point of view, most products of evolution work in a manner that canada goose outlet las vegas is suboptimal. uk canada goose

Canada Goose Parka 12. Homo sapiens does not occupy a privileged position in the grand evolutionary scheme. Canada Goose Parka

Canada Goose Online I canada goose outlet store new york think the main thing that not quite right about this is 5, novelty in evolution starts as a single mutation arising in a single individual at a single time point While this is essentially true, it misses out two canada goose kensington parka uk of the most canada goose outlet phone number significant novelties in the history of life, which were not created by mutation, but instead by instances of predation that went wrong and instead produced symbiosis, with one kind of cell living inside another. Canada Goose Online

buy canada goose jacket The first such event took place around 2 billion years ago, somewhere in the ocean. Prior to that moment, all life had consisted of small organisms called prokaryotes which had no cell nucleus or mitochondria (these are the tiny cellular structures that help provide you and me and giraffes and mushrooms with canada goose outlet energy). Everything changed when one unicellular life form, known as an achaebacterium, tried to eat another, called a eubacterium. On this one occasion the eubacterium survived inside its would be predator and became trapped, losing many of its genes to its host and eventually turning into a molecular powerhouse canada goose outlet store quebec the mitochondrion that produced energy from chemical reactions and was used by the canada goose outlet new york city new eukaryotic cell. These new eukaryotic life forms were canada goose outlet winnipeg address a weird hybrid, composed of two different organisms. They were our ancestors. buy canada goose jacket

A second, similar, event occurred around a billion years ago, when a eukaryotic cell, complete with mitochondria, canada goose outlet niagara falls engulfed a eubacterium that had long ago evolved the trick of acquiring energy from sunlight, through photosynthesis. Predation went wrong again, and another form of symbiosis eventually appeared. This gave rise to algae and eventually plants, in which small organelles called chloroplasts, the descendants of the intended eubacterial victim, turn light into energy for the benefit of the eukaryotic host.

canada goose clearance sale What happened after these events took place was entirely down to natural selection, following the kind of processes that Dan describes above. But the source of the novelty and pace his point 10 above, these were truly novel organisms was not mutation, but an incredibly unlikely pair of events. canada goose clearance sale

canada goose clearance It is striking that these two acts of predation gone wrong were able to open up the potential of life in ways that genetic mutation + natural selection have not been able to do in 3.5 billion years of evolution. Life on Earth without mitochondria prokaryotic canada goose outlet germany life is limited to the microscopic because of the physical limits imposed on the transport of matter, energy and information from the environment into the inside of the organism. In the absence of an additional, powerful energy source, prokaryotic life cannot carry out those operations beyond certain tiny physical dimensions. The co option of the energy producing mitochondria first enabled eukaryotic cells to grow large, and then, eventually, to become multicellular. Mutation and natural selection were not able to do this. Similarly, no eukaryotic organism has on its own mastered the trick of evolving photosynthesis; the only way the ancestors of plants were able to do this was through symbiosis with photosynthetic bacteria. canada goose clearance

buy canada goose jacket cheap Other people have pointed this out on Twtter; Dan response was to redefine in point 5 canada goose outlet store toronto as heritable change Which is fine, but would have been canada goose outlet online uk clearer had he said so from the outset buy canada goose jacket cheap

It looks basically great in terms of evolution = genetic change (in allele frequencies) over time. But there nothing about speciation and its converse common ancestry. One canada goose outlet new york could completely understand and agree with everyone of his points, but not understand or agree that humans are canada goose outlet belgium related to dogs, redwoods, morels, and E. coli.

Canada Goose online Without common ancestry of canada goose outlet 2015 all of currently living species, there would not even be a cohesive field of biology, with common principles/facts about central dogma, genetics, cell devision, metabollism, etc. nothing in biology makes sense except in the light of evolution! Canada Goose online

I am also concerned about Evolution cannot create something out of nothing; there is no true novelty in evolution. as well. It seems that a lot of new features acquired by life over the past 500 Myr or so indeed arose from canada goose factory outlet modified duplicated genes or repurposed genes, canada goose outlet online store but what if we go back 3.5 or 4 billion years ago, when life was just beginning? Was one gene formed at random on a clay mineral template, sucked into a proto cell, and then all new genes in all subsequent bacteria and archea are mutated duplicates of this one?

cheap Canada Goose It an interesting definitional canada goose outlet uk question. Quantum events can reasonably be said to come from nothing. And Inflation erased information about what might have preceded, so, even if it might have made sense to say that something Inflation, said something doesn exist for any meaningful definition of the word. Division by zero, http://www.mycanadagoosejacket.org effectively answers are equally valid, and so therefore no answer is valid. cheap Canada Goose

Causality is a notion of extremely limited utility. Is the water boiling because of the heat added to it from the stove, or because you want a cup of tea? You can use causality as a tool for forward projection and planning I want a cup of tea, then I should set the pot on the stove, and so on. But inverting it and looking backwards why do you want a cup of tea, and shouldn that be the cause? And so on.

Very interesting, and a pretty useful list from Dan.

canada goose I too jumped on 5, in that at times an upswing in fitness does not always emerge after a single mutation. Sometimes this happens after an earlier, effectively neutral or canada goose outlet toronto factory slightly deleterious mutation is combined with a 2nd mutation. There are different canada goose outlet store uk examples of this, and ironically Larry Moran has a post about this sort of thing today. canada goose

canada goose coats on sale But I think it is a good list overall, and I would rather not add a lot of extra s to it lest it become overly long. canada goose coats on sale

canada goose uk black friday 8. Evolution occurs at the population level; individuals do not evolve. An individual can only make an evolutionary contribution by producing offspring or dying childless. [emphasis added] canada goose uk black friday

canada goose uk shop I take issue with the part I emphasized. An individual can also make quite significant evolutionary contributions by influencing the breeding and survival of others. All of agriculture is the result of humans directing the reproduction and death of other organisms, and it long been canada goose outlet factory a staple of human society to apply similar principles to ourselves. Arranged marriages? Infanticide (especially of the children of rivals)? Jealous spouses murdering rivals canada goose outlet us and potential rivals canada goose uk shop.

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