https://tinyurl.com/microcosmicgod
I won't spoil it for you. It's still a great bedtime read.
Unless you mean, no one has seen it happen inside a lab? But that's not true either.., accelerated evolution experiments with uni-cellular species with different "sexes", leading to reproductive isolation (ergo, speciation) has been shown [3].
How about multi-cellular species where this has been demonstrated at the broad genetic & physiological / behavioral level? That's been done too. See these two for a review of some of the work [4,5].
[1] https://academic.oup.com/zoolinnean/article/3/9/45/2701607
"On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection", Darwin & Wallace
[2] https://en.wikipedia.org/wiki/Speciation#The_effect_of_sexua...
[3] http://www.pnas.org/content/112/14/4405
"Molecular coevolution of a sex pheromone and its receptor triggers reproductive isolation in Schizosaccharomyces pombe"
[4] http://www.pnas.org/content/97/23/12398
"Natural selection and speciation"
[5] http://www.pnas.org/content/102/suppl_1/6522
"The genetic basis of reproductive isolation: Insights from Drosophila"
And all this from a cursory 5 minute search (including time to type this up)..
Your citation #3 states "In conclusion, we have succeeded in creating an artificial reproductive group that is isolated from the WT group." They artificially castrated a species; that is not evolution.
Citation #4: "The authors suggest that reproductive isolation has evolved in situ as a result of...". Again, not proof.
Citation #5 adds no value at all: "Although the sample of genes characterized thus far by various laboratories remains small, and concentrated in the genus Drosophila, I suspect that these patterns may prove general, although likely not universal. Our recent work, along with that of several other groups, also suggests that the selection underlying the evolution of speciation genes may sometimes assume a surprising form, response to intragenomic conflicts, perhaps involving meiotic drive." Keywords: suspect, suggests, may, perhaps
You may want to believe evolution so badly, but science doesn't have the proof yet, and that is a fact.
That’s utter nonsense. No general definition of evolution (whether as a general concept or whether via a specific mechanism, such as natural selection) requires sexual reproduction. Only some mechanisms do (in particular, obviously, sexual selection). Evolution by random mutation and natural selection (the core concept of the modern synthesis, which underpins all of modern biology) is completely independent of sexual reproduction.
> For sexually reproducing organisms, speciation occurs when an organism can no longer reproduce with its predecessor
You’re misunderstanding something that is used for convenience, but is really a vast simplification. In reality speciation isn’t one defined point in time (hence it’s idiocy to ask what species the parents of the first human were — evolution is gradual!). To name just one specific example where your example breaks down: ring species [1].
> […] science still can't prove [speciation in sexually reproducing organisms].
Once more, that’s utter nonsense (e.g. [2]).
[1] https://en.wikipedia.org/wiki/Ring_species [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1635482/
Now all you have to do is prove that a "random mutation" created a new species.
Second, you cite the Ring Species wiki, which links to an article which argues ring species don't exist. The proof is nebulous. https://whyevolutionistrue.wordpress.com/2014/07/16/there-ar...
"On human terms, the LTEE generations span the equivalent of well more than a million years of human evolution."
Haven't we evolved a lot more in 68,000 generations than the bacteria have? Or put another way, all the bacteria has done in this time period is go from consuming glucose to citrate, nothing else in its shape, structure, etc. So how did humans and other creatures evolve so much over 68,000 generations?
I am 100% on board with evolution, I'm just curious about this. This is only 6-7 times more generations than when humans split from chimps (quick google search said 6-7 million years ago).
Is it because we have way more interaction with our environment and these bacteria are just in a little petri dish? Sounds likely.
Has anyone ever heard of people questioning evolution? I think he was saying something about how impossible it would be to have every single thing we see in nature be pre-written in DNA - it has just been all expressed in genes over the millennia through natural selection.
You can observe the same thing in genetic algorithms, where crossover ("sexual" reproduction / mixing of two candidates) is often performed because it creates more viable offspring than simple cloning with mutations.
This is just amazing. Kudos to this team of scientists.
Here's a summary I found surrounding the issue. https://arstechnica.com/features/2008/06/conservapedias-evol...
