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Let's make it extremely simple for you: Can you name a single species whose speciation-by-random-mutation we have witnessed? Have I missed the Down-syndrome on

Let's make it extremely simple for you: Can you name a single species whose speciation-by-random-mutation we have witnessed? Have I missed the Down-syndrome one (or any analogous known gene mutation) which has been continuously procreating all this time? Besides the fact that Down-syndrome is a terrible example since Down-syndrome-parents would not necessarily produce offspring with the same genetic disorder, hence no speciation-by-random-mutation. I thought people learn this stuff in HS...

Thiez 2y ago
"Species" itself is a vague concept in biology. It makes sense at a HS level like "dog is a different species from elephant" but it breaks down in more complex cases, e.g. lion + tiger. Ring species are also a nice example where individuals from A breed with B so same species, B breeds with C so same species, …, but A does not breed with E so not the same species. If we exterminate the populations B, C, and D, A and E are now definitely different species, so I would argue we could observe speciation that way? But while the populations between them exist, it's more muddled. Since evolution moves slowly there are two ways to see it in action: either you experiment with a species that reproduces very rapidly, or you look at fossil records. For the first type bacteria are usually used, but since bacteria don't have sexual reproduction a naysayer could always cast doubt on whether a new species has truly been created (are any two individual bacteria really the same species? Who can tell, short of verifying base-by-base equality of their DNA), so it won't convince someone who is determined to doubt evolution. For the fossil records we have literal mountains of evidence where the development of existing and extinct species can be observed. But I imagine you won't count that as "witnessing" it happening. I feel like many people who doubt evolution use a standard of evidence that they don't use for any other scientific theory, and probably not for any other area in their life either. Other people have mentioned it already: plate tectonics, almost all of astronomy... we could extend it to history too. Did you witness the founding of the United States? If documented history count as proof of stuff like founding of the US, the civil war, and the first world war, then why don't fossils count as proof of evolution?
- jdthedisciple 2y ago
  "Species" simply means can interbreed AND produce fertile offspring. This why your lion + tiger is not some special case, it trivially fails the definition: Their offspring are sterile. Now ring species as you describe have not been shown to exist. Let me refer you as well to this brilliant article by an evolutionist explaining that: https://whyevolutionistrue.com/2014/07/16/there-are-no-ring-species/ https://whyevolutionistrue.com/2014/07/16/there-are-no-ring-... In short, the suspected ring species were found to produce fertile offspring when interbreeding at the ring-closing point (!). > The authors [...] found, contrary to previous information, that there are indeed some hybrids (fertile ones, since they backcross) produced where the ring closes at the top, so they aren’t really acting like full biological species. So we cannot be certain that where the ring closes, inter-breeding is impossible, because it has been shown to occur. Further: > In the end, the authors conclude [...]: there are no good examples of ring species in nature --- It's not about "doubting" in a religious sense. As an intellectual and academic I simply reserve the right to challenge and poke holes as rigorously as I can into any theory presented to me. What I found is that speciation-by-random-mutation appears to fail my (admittedly difficult but nonetheless valid) challenge. As for plate tectonics: Look, if I were to say the evidence in my eyes does not support the theory well enough, would that make me unscientific? Of course not! The best counter-example I just posted are ring species - scientists once had extreme confidence in their existence, only to be disappointed after new findings.
  - Thiez 2y ago
    The brilliant article you post argues against ring species, but it does so by demonstrating geographic breaks that caused... speciation. So perhaps ring species as a concept sadly aren't as much a thing as was suggested in my HS days (I suppose science moved on, thanks for updating my knowledge) but if you accept the contents of that article then you must also agree that speciation is a thing that happens. But in the interest of considering the topic from an intellectual and academic point of view, what is your proposed alternative explanation for the huge number of species we see today, apart from evolution and speciation?
    - 2y ago

Thiez 2y ago

"Species" itself is a vague concept in biology. It makes sense at a HS level like "dog is a different species from elephant" but it breaks down in more complex cases, e.g. lion + tiger. Ring species are also a nice example where individuals from A breed with B so same species, B breeds with C so same species, …, but A does not breed with E so not the same species. If we exterminate the populations B, C, and D, A and E are now definitely different species, so I would argue we could observe speciation that way? But while the populations between them exist, it's more muddled. Since evolution moves slowly there are two ways to see it in action: either you experiment with a species that reproduces very rapidly, or you look at fossil records. For the first type bacteria are usually used, but since bacteria don't have sexual reproduction a naysayer could always cast doubt on whether a new species has truly been created (are any two individual bacteria really the same species? Who can tell, short of verifying base-by-base equality of their DNA), so it won't convince someone who is determined to doubt evolution. For the fossil records we have literal mountains of evidence where the development of existing and extinct species can be observed. But I imagine you won't count that as "witnessing" it happening. I feel like many people who doubt evolution use a standard of evidence that they don't use for any other scientific theory, and probably not for any other area in their life either. Other people have mentioned it already: plate tectonics, almost all of astronomy... we could extend it to history too. Did you witness the founding of the United States? If documented history count as proof of stuff like founding of the US, the civil war, and the first world war, then why don't fossils count as proof of evolution?

jdthedisciple 2y ago
"Species" simply means can interbreed AND produce fertile offspring. This why your lion + tiger is not some special case, it trivially fails the definition: Their offspring are sterile. Now ring species as you describe have not been shown to exist. Let me refer you as well to this brilliant article by an evolutionist explaining that: https://whyevolutionistrue.com/2014/07/16/there-are-no-ring-species/ https://whyevolutionistrue.com/2014/07/16/there-are-no-ring-... In short, the suspected ring species were found to produce fertile offspring when interbreeding at the ring-closing point (!). > The authors [...] found, contrary to previous information, that there are indeed some hybrids (fertile ones, since they backcross) produced where the ring closes at the top, so they aren’t really acting like full biological species. So we cannot be certain that where the ring closes, inter-breeding is impossible, because it has been shown to occur. Further: > In the end, the authors conclude [...]: there are no good examples of ring species in nature --- It's not about "doubting" in a religious sense. As an intellectual and academic I simply reserve the right to challenge and poke holes as rigorously as I can into any theory presented to me. What I found is that speciation-by-random-mutation appears to fail my (admittedly difficult but nonetheless valid) challenge. As for plate tectonics: Look, if I were to say the evidence in my eyes does not support the theory well enough, would that make me unscientific? Of course not! The best counter-example I just posted are ring species - scientists once had extreme confidence in their existence, only to be disappointed after new findings.
- Thiez 2y ago
  The brilliant article you post argues against ring species, but it does so by demonstrating geographic breaks that caused... speciation. So perhaps ring species as a concept sadly aren't as much a thing as was suggested in my HS days (I suppose science moved on, thanks for updating my knowledge) but if you accept the contents of that article then you must also agree that speciation is a thing that happens. But in the interest of considering the topic from an intellectual and academic point of view, what is your proposed alternative explanation for the huge number of species we see today, apart from evolution and speciation?
  - 2y ago