Polaris #fundie

Polaris #fundie atheistforums.org

Well there are two types of evolution: macroevolution, which is much easier to accept, and microevolution.

The key with macroevolution is taking the evidence and extrapolating a pattern.

Microevolution is more about taking the theory of evolution and trying to assert it is happening currently in a certain species over a very limited amount of data from genetic divergence within a control group over time period significantly less than what should be used to determine if evolution is occurring.

[LOL, macro and micro refer to our perspective of the event, not the process. Don't start this tired shit. Microevolution -is- macroevolution. Titl the lens into closer focus, pan out over wider focus. End of.]

Going back and forth between genetic changes is not what I call evolution. Just because a species is undergoing Darwinian mechanisms does not mean it is really experiencing evolution.

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old comment by John_in_Oz

He raises an interesting question.
The example I'm thinking of was written about by Olivia Judson in the New York Times. http://opinionator.blogs.nytimes.com/2008/07/22/a-natural-selection/
She writes under the pen name 'Dr Tatiana'. Do yourself a favour and read her articles. Read her book. Watch the TV episodes. Read her academic papers.
Her example came from the same Galapagous Islands which famously inspired Darwin. Weather causes changes in the food supply which causes changes in the relative abundance of genes within the species. That change is what Dawkins in 'the Greatest Show on Earth' p33 defines as "what we mean by evolution". However, weather changes, and the genetic effects change with it. The relative abundance of genes shifts back and forth. Has the species evolved? Dawkins himself did limit evolution to systematic increase or decrease in the frequency of genes.
Judson calls it evolution, as I would as well, but if a species' gene pool ends up the same as what it started with, even though it has been subjected to Darwinian mechanisms of natural selection of genes, has it evolved? And if not, can we claim to have observed 'evolution in action'?
I'm going to end up disagreeing with him, but he's raised an important nuance to be aware of when discussing evolution.
If we think of evolution as the production of novel alleles that then spread through the population by Darwinian natural selection, then presumably he's right that we haven't yet observed it in action. Of course, for that to be true, the alleles for the effects that others mention above, would have to have been already present in the population at some frequency.

old comment by

under lab conditions, scientist studying the evolution of bacteria got a bacteria that uses glucose for energy, or "food", to start using fructose as energy as well(the bacteria in question could not process fructose originally, no change in control group).

how? by introducing them to an environment that had required amounts of glucose for the bacteria culture to survive, and fructose. about a 50/50 split. after a certain amount of time, they moved bacteria in the culture to a new environment that was predominantly fructose. they found that, most of the bacteria died shortly after the change, but some did not. some had spontaneously(seemingly) gained the ability to process fructose. after allowing the bacteria to reproduce and introducing it to an all fructose environment, and the bacteria continued to reproduce, consuming fructose for energy.

this is a perfect example of how evolution works. a stress is placed on a being, and individuals with accidentally mutated genes that provide a beneficial trait which makes them able to deal with their environment better, tend to survive. the first bacteria that gained the ability probably couldn't do it very well. a very low efficiency would be probable. but that bacteria can now survive just that much easier, and when nothing is threatening its reproductive potential, it will thrive. after enough time passes, and enough generations, the fructose consuming bacteria will get better at it, until they have a fully developed ability to process fructose efficiently.

you could not call the fructose consuming bacteria the same species as the original, as the original could not process fructose, the control group did not see any changes, and you know beyond all doubt that no fructose consuming bacteria went IN to the petri dish(lab conditions, after all), so where did they come from? evolution is the only logical explanation(that does not depend on the existence of sky-daddy)

old comment by Felix Wilde

Certain bacteria consume nylon (a substance which has existed for well under a century). A fungus found in Chernobyl consumes radiation from the contaminated environment (just google "radiophagic fungus"; it's awesome! It uses melanin like plants use chlorophyll, so it's black in colour). A mosquito exists which lives only in subterranean train systems (the London Underground mosquito). Genetic analysis of these species has revealed their lineage and, along with other studies, that they are unique species.

I don't have a plant example, but that's three kingdoms. Off the top of my head, I can think of three species from three different kingdoms which are adapted to environments humans have made in recorded history. They could not have existed until very recently.

Care to explain how that's not macroevolution?

PS - Does anyone know if there is an online list of recently-evolved species? I'd love to peruse it for other interesting examples. Especially animals, as they tend to be the most striking examples. I like how the human head louse and body louse seem to be mid-speciation at the moment too... Not capable of breeding due to behaviour, but still genetically compatible. And of course ring species are similarly astonishing examples... Damn, biology is so much fun!

“Well there are two types of evolution: macroevolution, which is much easier to accept, and microevolution.”
So, one DNA gene changing a function in an organism, without much physical cahnge woul be microevolution. You think that something like A, B, AB, and 0 blood gaining a Rhesus factor, to make APos, Bpos, 0pos and ABpos, is less acceptable?
Major physical changes, like a moose’s antlters, or an elephant’s trunk, or a whale’s tail flukes, that’s more acceptable to you?
You made a typo.

“The key with macroevolution is taking the evidence and extrapolating a pattern.”
The pattern is the gradual accumulation of microevolution changes.

“Microevolution is more about taking the theory of evolution and trying to assert it is happening currently in a certain species over a very limited amount of data from genetic divergence within a control group over time period significantly less than what should be used to determine if evolution is occurring.”
TELL me what SHOULD be the window to determine if the frequency of certain allelles changes over time within a species. And how do you know?
There’s no time limit for macro or micro evolution. We compare a gene pool at two different times. If the average DNA of members is different between those two times, then evolution has occurred.
That’s it. All it takes.

“ oing back and forth between genetic changes is not what I call evolution.”
WHo gives a shit? Seriously. You’re on the outs, here, with your personal definition. Learn what the real one is or don’t but don’t pretend your made-up-shit has any bearing on the discussion.

“Just because a species is undergoing Darwinian mechanisms does not mean it is really experiencing evolution.”
That’s exactly what evolution IS, genius. Life on this planet reproduces imperfectly. Trends develop and some aspects are saved, rising to dominate future generations.
There is NO DIFFERENCE between micro and macro evolution except for the accumulation of more results.

Polaris #fundie atheistforums.org

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