Why is evolution so controversial?

EnjoyEdited by RAZD, : typical creationist attempt to will away the evidence

No, your position is a joke, whether you realize it or not -- because it has been invalidated by objective empirical evidence that contradicts what you claim. Your position is a joke because you fail to understand the evidence for a population bottleneck from two different sources are talking about the same singular event. Your position is a joke because you think "between 50,000 and 100,000 years ago" is a 50,000 year long period rather than the approximate range within which a bottleneck event occurred. Another way to say it is that 75,000 +/- 25,000 years ago a population bottleneck event occurred. Curiously this compares quite well with the data from newer more accurate source that says the same singular population bottleneck event occurred ~70,000 years ago. One event, two different sets of data that are conscilient, reinforcing each other and giving us greater confidence in the results. There was only one bottleneck period in Homo sapiens history. Because mutations continue to occur and selection continues to occur. After a stochastic bottleneck event the selection pressure on the remaining population for stable phenotype is removed and so diversity will increase after that event at a higher rate than in a mature population in stasis with their ecology. Curious as to how you arrived at the "10,000 individuals" number -- without documentation and evidence it is just another claim you have pulled out of your posterior region. Not necessarily. Populations in genetic isolation have different selection pressures and will adapt via fitness selection in different ways. If the habitats are very similar then the selection process will be similar. If there is occasional gene flow then mixing with the main population will still occur. Moving into pocket habitats does not mean genetic isolation occurs. Why? If subpopulations remain genetically isolated then speciation can occur, just as has happened in the past (there are several sister Homo species in the past, one of them is Homo neanderthalensis).It is obvious from the world around you that the human population is NOT homogeneous, but has many varieties (races) that are observably distinct even though inter-breeding can and does occur. This is no different that different varieties in other species showing some distinctive geographical variations while maintaining inter-breeding capability.But there is no requirement for all Homo sapiens descendants to stay in the Homo sapiens species. Divergence can occur as it has in the past.And distinct varieties can develop while remaining in the Homo sapiens species and not staying homogeneous in non-breeding areas of the genome. Not true. Genetic mapping of genetic variations shows distinct geographical branching of several genotype variations within the species as a whole.People are all classed within the Homo sapiens species because they can (and do) inter-breed, not because their whole genomes are similar. Again, there was only one (1) bottleneck event. Nor does it have to be homogeneous, it just requires sexual compatibility for reproduction to remain in the same species. That is a small subset of the genome. And again you fail to understand that the period of the extinction event was not 50,000 years but a brief period within an approximate 50,000 year accuracy range -- at some point between 50,000 years ago and 100,000 years ago a brief bottleneck event occurred ... at some point around 75,000 years ago (+/- 25,000 years) a brief bottleneck event occurred -- an estimate that is now confirmed by new data showing that approximately 70,000 years ago a brief bottleneck event occurred -- ONE event, One brief bottleneck event. False (1) -- Do some research on punctuated equilibrium and the evidence for much longer periods of stasis in some species.False (2) -- our species origin occurred circa 160,000 years ago.Repeating false claims and opinions does not make them any more valid than when they were first refuted, it just shows a stubborn inability to accept your errors. Cognitive dissonance in full display.Enjoy.Edited by RAZD, :

Indeed.And when the only constraint on the equations is having the same beginning and end points, while ignoring the intermediate points, it becomes mundanely obvious that the number of possible equations is infinite.It also becomes mundanely obvious that virtually all such equations will fail to model the intermediate points. Some will, of course, model occasional intermediate points, in the way a straight line and a sinusoidal curve will model intermediate points, while diverging significantly in other places.This demonstrates that math can model reality, but cannot constrain it or control it or force reality to match the model.Enjoy

Curiously I have already presented it -- that you failed to understand it is not my fault. (Search thread for your post with "supper" in it). Which I have been. You confuse two different avenues of data as being about two different events, instead of one confirming the other, and you confuse uncertainty with exactly when within a 50,000 year window that event occurred with it lasting 50,000 years. These are comprehension problems on your end.You continue to make these mistakes. If you don't want a novel in response then reduce the errors in your posts to one at a time. Curiously this is in response to posts you have made with these numbers, so you are accusing me of failing to provide citations for material you used? Really?Perhaps you need to look back at where you got those numbers. So you take a speculative extreme view as fact because it suits your beliefs ...Another approach would be to start with understanding how bottleneck\founder events affect a species in general, and then seeing if that applies or not to the human situation.Population bottleneck - Wikipedia

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A population bottleneck is a sharp reduction in the size of a population due to environmental events (such as earthquakes, floods, fires, or droughts) or human activities (such as genocide). Such events can reduce the variation in the gene pool of a population. After an event, a smaller population (of animals/people), with a correspondingly smaller genetic diversity, remains to pass on genes to future generations of offspring. ...

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Population bottleneck followed by recovery or extinction

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... The population of American bison (Bison bison) fell due to overhunting, nearly leading to extinction around the year 1890, though it has since begun to recover (see table).

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Year	American bison (est)
Before 1492	60,000,000
1890	750
2000	360,000

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A classic example of a population bottleneck is that of the northern elephant seal, whose population fell to about 30 in the 1890s. Although it now numbers in the hundreds of thousands, ...

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From this simple sampling of actual data and information, three things should be mundanely obvious to the casual observer:

1. that the recovery from a bottleneck\founding event is highly variable between one extreme leading to extinction and another limited by the malthusian pure growth model (that in fact there are an infinite number of possible recovery rates), and
2. that thousands of years of recovery did not occur for bison or elephant seals^(*),
3. that recovery depends on a number of factors involving the fitness of the population to survive and reproduce in their current habitats, not on some pre-determined mathematical model of growth.

^(*) which depends on your definition of "recovery" -- you could argue that the (full) recovery has not occurred yet because those animal populations have not yet reached their previous size and genetic diversity. This of course contradicts your claim that the recovery period is characterized by a constant population with zero net growth.Or you could argue that recovery depends on when the species reaches a level of population and genetic diversity that they are no longer considered "endangered" ... another subjective categorization.Or you could argue that once the population starts to grow that it has recovered.Either way we do not see a necessary flat-lined recovery for "tens of thousands of years" ... which is your (indefensible\ill-defined) argument.If the bottleneck\founder event is stochastic (chance unrelated to fitness) and does not cause an extreme change to the habitat, then there is every reason to believe that the survivors are a random sample of the previous population that was adapted to the ecological habitat that exists following the event and should be well positioned to grow and evolve to fill the available resources and carrying capacity of that habitat.Thus an event that lasted one generation in affecting the habitat would be followed by near malthusian pure growth recovery until it started reaching the carrying capacity of the habitat, presumable the level of population before the event. Perhaps you should stop denigrating information and pay attention to the facts and empirical evidence rather than letting pet beliefs lead you off into untenable positions.Enjoy

And I like to use white backgrounds to gifs with transparent backgrounds to make them more readable, especially when you have dark colors against the dark blue background: The black dot point is unstable because the population tends to move away from that point towards either growth or death (extinction). The orange dot is stable because the population tends to return to that level because it is the carrying capacity for that ecology, and small oscillations can occur -- as has been observed in many cases.The tendency for a population to move along this theoretical curve is dictated by the difference between births and deaths -- as has been discussed already on this thread regarding your argument (see Message 627 for example):

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Of course, that doesn't mean that you would be able to understand what the Wikipedia article says, considering your demonstrated inability to understand your own sources: Biological exponential growth. It gives the formula as a derivative:

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If, in a hypothetical population of size N, the birth rates (per capita) are represented as b and death rates (per capita) as d, then the increase or decrease in N during a time period t will be:

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dN/dt=(b−d)N

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(b-d) is called the 'intrinsic rate of natural increase' and is a very important parameter chosen for assessing the impacts of any biotic or abiotic factor on population growth.

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Despite different variable names, that is the same equation that Olnick develops. When you integrate it and clean it up a bit, then it becomes the familiar:

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p(t) Ne^(b-d)t

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where p(t) is the function of population size with respect to time,
and your r = (b-d)

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A little inspection will show you that your r = (b-d) is the r_o above.In addition, it should be mundanely obvious that after a stocastic event that does not permanently alter the habitat for a surviving population that r_o will be greater than zero because selection pressure deaths will be less -- the habitat is capable of supporting a much larger population.If you want to argue your point you need to provide evidence that r_o = 0 and must remain at 0 for the time after the bottleneck\founding event.You haven't. All you did was solve the 0 point for r_o -- which is mundanely true, but doesn't constrain future growth, the ecology does that (not math). The next generation will have its own r value.You have not shown any cause for the r to stay at 0 for the black dot location. That "instability" is the tendency for population size to change, which in terms of population growth and adaptation is that a population that is adapted to the habitat will tend to increase until it reaches the carrying capacity, while a population that is not adapted to the habitat will tend to decrease until it is extinct -- ie the extremes on this graph: Where there are an infinite number of possibilities depending on the adaptation to the habitat (fitness within the ecological network). Only if the adaptation to the habitat (fitness within the ecological network) is unknown and uncertain. From the graph above we see an infinite number of possibilities between rapid growth and rapid death, balanced in a wide plane around a stable zero growth population.In a bottleneck event we KNOW that the species is well adapted to the habitat if the habitat is not permanently altered, from its previous history in that habitat.We also KNOW that populations do not behave along pure mathematical model lines, that the ecology varies not just the species, and that one bad year can be followed by one good year, that the rate of population growth, the r=(b-d) can change from negative to positive and oscillate around any value. Math doesn't control\constrain\mandate reality.Enjoy.Edited by RAZD, : finishing post

Rather than being logically consistent in your application of Occam's razor you only apply it to the benefit of your argument. You can't even be consistent in two consecutive posts ... Confirmation Bias, Cognitive Dissonance, cherry picking and ide fixes, are not the tools of an open-mind or an honest skeptic, and continued belief in the face of contradictory evidence is delusion.EnjoyEdited by RAZD, : ...

And where did you demonstrate that they were wrong? Post number and quote please. I am not inventing the bottleneck event -- that is what the data shows from a number of different sources. One recent DNA study showed that it occurred at the same time as the Toba eruption, thus providing support for that theory. So, to put it in plain english, evolutionary scientists need to invent "impossible bottleneck scenarios" because there is evidence for a bottleneck event.Fascinating.Even more curious is the fact that these same scientists did not at once claim there was a bottleneck event, rather they investigated the possibility of a bottleneck event and went looking for evidence that this has in fact occurred.What we find is increasing evidence from various other sources for such an event at about the same time, evidence that is conscilient and that supports such an event. Curiously this is no different functionally from any species moving into a new habitat and being able to exploit the opportunities there, increasing the overall population.Humans also poison and trash their habitats to an unprecedented level untouched by any other species and ignore the evidence of global changes due to their actions.Why are there so many deaths from starvation every year if we are so good at modifying our ecological resources.Do the increases in droughts in the west from global climate change improve our habitat carrying capacity? Until it isn't.It varies from year to year oscillating as it is affected by the ecology around it, until it begins to be affected the carrying capacity of their current habitat when growth slows down, birth rates drop, death rates increase. Or in plain english: you can continually modify the equation so that it applies to each generation, each year, each week, each day, in order to force it to fit the observed objective empirical data that show that the formula unmodified is inadequate to model the date in even the most cursory application.Or to be plainer still: you can't use the equation to predict the population for any time period where you have not made adjustments to fit actual known data.Or to take it one step further: the same process can be used to adopt any of an infinite number of function to match the actual data, even sections of straight lines or sine curves or circles, to force a fit between any (each and every) two known data points.Or to be plainer still: until it becomes useless as a predictive model.If you modify the formula to fit situation A
and modify it again to fit situation B
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and modify it again to fit situation Y ...Then you cannot predict the results of situation ZEnjoy.Edited by RAZD, : clrty

The amount of Neanderthal DNA in humans is <5%.This is consistent with some occasional interbreeding during a period of transition from one species into two distinct breeding species as interbreeding fertility decreases with succeeding generations.We see occasional fertile cross breeding between horses and donkey, and yet that doesn't mean that they are one species instead of two. Same with Zebras. Rather this is evidence of common ancestry in the final stages of reproductive isolation. The evidence is that the frequency was low and that it became lower. What is your definition?My definition involves speciation events characterized by separated breeding populations that do not interbreed, whether due to genetic infertility or behavioral patterns, where gene flow is reduced to negligible levels and habitat adaptation is moving in different directions.Now I will specify that I don't think there is a one-size fits all definition for species, just one that is practical in application: a group of organisms that do not normally interbreed with other groups of organisms. Certainly some groups can be forced to breed with others: lions and tigers, camels and llamas, horses and donkeys, etc etc etcIt is evident that interbreeding between sapiens and neander was in that realm of very low occurrence during the time period of early overlap. For interbreeding to occur there has to be genetic compatibility, opportunity, and attraction\willingness.This doesn't include anagenic speciation, also known as "phyletic speciation", as we are clearly talking about cladogenic speciation involving an evolutionary branching event of a parent species into two or more closely related sister species, and the formation of nested hierarchies. They are members of Homo genus so this is rather more indicative of making sloppy confused claims on the order ofNeanderthals are clearly not a different species than apes ...But they are a different species than Homo sapiens.Species | The Smithsonian Institution's Human Origins Program

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While the exact number of early human species is debated, on this page are links to summaries of the early human species accepted by most scientists. ...

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While some of the early species categories maybe debated, the classification of neanderthals is not:Homo neanderthalensis | The Smithsonian Institution's Human Origins Program

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Neanderthals (the ‘th’ pronounced as ‘t’) are our closest extinct human relative. Some defining features of their skulls include the large middle part of the face, angled cheek bones, and a huge nose for humidifying and warming cold, dry air. Their bodies were shorter and stockier than ours, another adaptation to living in cold environments. But their brains were just as large as ours and often larger - proportional to their brawnier bodies.

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Distinct physical differences, different phenotypes, that don't match Homo sapiens physical characteristics.There is an interesting discussion of DNA here. You'll need to provide me with more details than that. What I found is a list of publications onPage not found – Department of Anthropology – UW—Madisonand Population Bottlenecks and Pleistocene Human Evolution, published while he was at U of Utah, and which doesn't appear to support your claim, but rather makes a different argument altogether.He wrote (or co-authored) many papers -- which one are you citing? Are you a student of his? Curiously I have not see any evidence from you that shows common descent does not occur, which would be remarkable given that speciation events have been observed, thus demonstrating common descent. All you have provided is your opinion.Enjoy.

Ah, so you did not demonstrate this and thus cannot provide the post number and a quotation, but devolve into ad hominem logical fallacies to lessen the cognitive dissonance between your claiming to have done something and your inability to show that you have done something.Classic.Enjoy.

There are plenty of critics within the field -- where do you think the "explosion of new supposed of hominids" comes from? Dogmatic pontificators?ALL science adapts to new information -- why would evolution be different?The question on this thread is "Why is evolution so controversial?" and you have made an interesting, convoluted and sometimes funny argument, but not one that - even if accepted - would change biological evolution teaching or alter the Theory of Evolution.Your problem is more internal inconsistency and failure to address known facts of population growth.Enjoy.

additional humorous claims by Zaius* the human growth is exponential, and that variation in actual population numbers from the idealized "pure growth" formula can be easily accounted for by adjusting the constants to different values for different time periods.* that one article talking about a human bottleneck occurring between 50,000 and 100,000 years ago and another article talking about a human bottleneck occurring 70,000 years ago are talking about two different events rather than the same event.* that the article on the human bottleneck occurring between 50,000 and 100,000 years ago means that the population stayed at the bottleneck level for 50,000 years with zero net growth.Some other minor claims were also made, but these (&Dr A's) are the main ones being discussed.EnjoyEdited by RAZD, : ...

They are unsubstantiated because YOU haven't provided citations from actual papers that document YOUR claims. The onus is on you to support claims you make, rather than expect people to go off on a wild-goose chase.Enjoy

Which means either you did not understand the article or the genetic study was in error -- the objective empirical evidence from several sources show the earliest Homo sapiens was 160,000 years ago: this makes the 5,000 year date for an earlier ancestor rather preposterous ... and applying Occam's razor (as you boast about using) would mean rejecting the single paper based on dubious genetics (see other replies to your post) instead of the consilient findings of generations of archaeologists from different countries\universities\foundations\etc.Curiously, the findings from fossils and radiometric dating are used to correct dating derived from genetic studies, because genetic studies make assumptions about mutation rates to calculate past events, and those assumptions are only valid when they are calibrated from known fossil dates.Genetic dates cannot be used to correct fossil dates. Rather they are like dates derived from the geological strata before radiometric methods were developed: they are relative dates that show the order of events without the actual dates of the events. Looks like silly misunderstanding to me ... he's talking about modern Homo sapiens versus Homo sapiens at the time of neanderthals (and he is still wrong for reasons sfs has pointed out in Message 720). Curiously your article claims that the rate of mutation is speeding up in modern humans compared to older Homo sapiens ... more reading incomprehension?Enjoy

It appears he is misreading John Hawks's papers and misunderstanding what they say.Enjoy

No, I'm in the middle of renovating an old house (1785 ish) and just uncovered some structural damage. Working to fix that is rather exhausting. Good idea. You might want to start with an outline of your argument and your major points with references to substantiate the basic claims.btw - I do usually read all posts in a thread I am interested, and what I limit is the number of threads I participate in.EnjoyEdited by RAZD, : ..