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"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

by 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?
  - jdthedisciple 2y ago
    It's a great question you raise, I honestly am extremely curious to learn that myself. I don't know. There are just a few aspects about it that don't fully compute in my mind. Take this for example, and bear with me for a moment: The earth is 4.5b yrs old. Say 4b yrs ago life began. Just in the past 500m yrs, there were 5 major extinction events, with perhaps 80-90% of species going extinct each time on avg. Homo erectus are said to emerge something shy of 2 mio yrs ago. Denisovans are much younger. Us and Denisovans are genetically one species (we could produce viable offspring). The same holds with denisovans and homo erectus This means we could probably viably procreate with homo erecti from ~2 mio yrs ago. So across 2 mio yrs, pretty much no speciation occurred with us (if at all ever, remember that is still conjecture if we're being strict). Now remember the last major extinction was just ~65 mio yrs ago. Yet there are what, 1-2 billion different species alive today? I know there is parallelization involved as the model goes, but to me it seems there was still very little time for all that to happen given that a single speciation event takes millions of years. I'm not saying evolution by speciation is false. I'm just saying perhaps it's insufficient. --- All of that said, speciation - or even evolution and science in general (!) - is not at odds with my religious beliefs anyway, as long as we are being true to what's certain and what's conjecture.
nickpsecurity 2y ago
“ 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” We’d have to see them turn into organisms that were very different from their original form or even multi-cellular. That would be closer to what evolution as origin of life says. Instead, most (all?) stay what they are with minor adaptations. We’ve also observed billions of other creatures over thousands of years that didn’t turn into new insects or animals. Evolution’s predictions on a macro-level have failed over a billion times for thousands of years. On the fossil record, evolution predicted continuous streams of changes in all directions with piles of viable, intermediate forms. We don’t see that. We do see large jumps from one type to another happening after extinctions where there’s lower populations. “use a standard of evidence that they don’t use for any other scientific theory” That’s exactly what evolutionists do. These failures of the theory, both observational and historical, would have had it tossed long ago like most theories that fail that much. Instead, they keep making excuses for it or emphasizing again that it must be true. That’s not science. That is like dogma driven by emotional or socio-political factors. Which also provably exist in institutions promoting it. So, it’s not science since it (a) is driven by non-scientific forces and (b) continues to fail the scientific method.
- Thiez 2y ago
  > We’d have to see them turn into organisms that were very different from their original form or even multi-cellular. That would be closer to what evolution as origin of life says. Instead, most (all?) stay what they are with minor adaptations. Let's take a look at the E. coli long term evolution experiment [1]! Here we see 12 initially identical populations of bacteria live through over 80k generations over a period of 36 years. During this time these isolated populations have undergone significant changes (such as becoming at least twice as large) that would surely qualify as "very different from their original form". One of the populations evolved the ability to aerobically grow on citrate. Not being able to do this is one of the defining qualities of E.coli, so it must surely qualify as becoming 'very different'. > We’ve also observed billions of other creatures over thousands of years that didn’t turn into new insects or animals. Evolution’s predictions on a macro-level have failed over a billion times for thousands of years. Speciation is usually a gradual process. There won't be a clear instant where yesterday there was one species and today it's suddenly two species. So in that regard there isn't a specific moment one could personally observe. And with the time between generations for animals being relatively long, we don't see much progress being made. What we do see around us is species in various stages of speciation. Here is a nice example of speciation starting for European birds [2] that is very recent. Also I would argue that the E.coli experiment has shown speciation in a human lifetime. > On the fossil record, evolution predicted continuous streams of changes in all directions with piles of viable, intermediate forms. We don’t see that. We do see large jumps from one type to another happening after extinctions where there’s lower populations. Citation needed? We have lots of species living today that we can trace to shared ancestors, like how we can trace humans, chimps, and orangutans to a common ancestor. It's true that speciation happens much faster after an extinction, this makes sense because extinction events cause previously occupied ecological niches to get opened up. In a static environment the rate of change is low because most species will be in a local optimum. Everything we see appears to confirm evolution. If you think the fossil record disproves evolution you should consider if it merely disproves your understanding of evolution, which may be incorrect. > That’s exactly what evolutionists do. These failures of the theory, both observational and historical, would have had it tossed long ago like most theories that fail that much. Instead, they keep making excuses for it or emphasizing again that it must be true. You mean biologists? To call evolution a failed theory is absurd, it's one of the most successful theories science has produced. It's supported by the fossil record, by DNA research, by bacteria becoming resistant to antibiotics and gaining the ability to digest plastics. By vestigial organs. By the way that early fetal development for mammals all looks the same. And there are no counter examples. No species appearing out of nowhere without a historical ancestor. No species with completely incompatible biology to our own. > That’s not science. That is like dogma driven by emotional or socio-political factors. Which also provably exist in institutions promoting it. So, it’s not science since it (a) is driven by non-scientific forces and (b) continues to fail the scientific method. You are seeing a conspiracy where none exists. If you have a better theory than evolution I encourage you to publish, and in a decade or two we will all know you as a Nobel prize winner. Maybe share it with us here on HN, I for one would be delighted to have been one of the first to have read this new theory. I sure hope it doesn't rely on an invisible undetectable magic man steering everything. Even if a theory is invented to supplant evolution, I guarantee it will include evolution. Just like General Relativity supplanted Newtonian Physics, turns out that they have pretty much the same results at the scales and speeds we usually find ourselves at. And just like the Earth being an oblate sphere instead of a perfect sphere. The basic idea of evolution is correct and any hypothetical future changes will be a refinement on what we already know, not a radically different thing. 1. https://en.m.wikipedia.org/wiki/E._coli_long-term_evolution_experiment https://en.m.wikipedia.org/wiki/E._coli_long-term_evolution_... 2. https://evolution.berkeley.edu/evo-news/speciation-in-real-time/ https://evolution.berkeley.edu/evo-news/speciation-in-real-t...

by Thiez 2y ago

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?
- jdthedisciple 2y ago
  It's a great question you raise, I honestly am extremely curious to learn that myself. I don't know. There are just a few aspects about it that don't fully compute in my mind. Take this for example, and bear with me for a moment: The earth is 4.5b yrs old. Say 4b yrs ago life began. Just in the past 500m yrs, there were 5 major extinction events, with perhaps 80-90% of species going extinct each time on avg. Homo erectus are said to emerge something shy of 2 mio yrs ago. Denisovans are much younger. Us and Denisovans are genetically one species (we could produce viable offspring). The same holds with denisovans and homo erectus This means we could probably viably procreate with homo erecti from ~2 mio yrs ago. So across 2 mio yrs, pretty much no speciation occurred with us (if at all ever, remember that is still conjecture if we're being strict). Now remember the last major extinction was just ~65 mio yrs ago. Yet there are what, 1-2 billion different species alive today? I know there is parallelization involved as the model goes, but to me it seems there was still very little time for all that to happen given that a single speciation event takes millions of years. I'm not saying evolution by speciation is false. I'm just saying perhaps it's insufficient. --- All of that said, speciation - or even evolution and science in general (!) - is not at odds with my religious beliefs anyway, as long as we are being true to what's certain and what's conjecture.

nickpsecurity 2y ago

“ 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” We’d have to see them turn into organisms that were very different from their original form or even multi-cellular. That would be closer to what evolution as origin of life says. Instead, most (all?) stay what they are with minor adaptations. We’ve also observed billions of other creatures over thousands of years that didn’t turn into new insects or animals. Evolution’s predictions on a macro-level have failed over a billion times for thousands of years. On the fossil record, evolution predicted continuous streams of changes in all directions with piles of viable, intermediate forms. We don’t see that. We do see large jumps from one type to another happening after extinctions where there’s lower populations. “use a standard of evidence that they don’t use for any other scientific theory” That’s exactly what evolutionists do. These failures of the theory, both observational and historical, would have had it tossed long ago like most theories that fail that much. Instead, they keep making excuses for it or emphasizing again that it must be true. That’s not science. That is like dogma driven by emotional or socio-political factors. Which also provably exist in institutions promoting it. So, it’s not science since it (a) is driven by non-scientific forces and (b) continues to fail the scientific method.

Thiez 2y ago
> We’d have to see them turn into organisms that were very different from their original form or even multi-cellular. That would be closer to what evolution as origin of life says. Instead, most (all?) stay what they are with minor adaptations. Let's take a look at the E. coli long term evolution experiment [1]! Here we see 12 initially identical populations of bacteria live through over 80k generations over a period of 36 years. During this time these isolated populations have undergone significant changes (such as becoming at least twice as large) that would surely qualify as "very different from their original form". One of the populations evolved the ability to aerobically grow on citrate. Not being able to do this is one of the defining qualities of E.coli, so it must surely qualify as becoming 'very different'. > We’ve also observed billions of other creatures over thousands of years that didn’t turn into new insects or animals. Evolution’s predictions on a macro-level have failed over a billion times for thousands of years. Speciation is usually a gradual process. There won't be a clear instant where yesterday there was one species and today it's suddenly two species. So in that regard there isn't a specific moment one could personally observe. And with the time between generations for animals being relatively long, we don't see much progress being made. What we do see around us is species in various stages of speciation. Here is a nice example of speciation starting for European birds [2] that is very recent. Also I would argue that the E.coli experiment has shown speciation in a human lifetime. > On the fossil record, evolution predicted continuous streams of changes in all directions with piles of viable, intermediate forms. We don’t see that. We do see large jumps from one type to another happening after extinctions where there’s lower populations. Citation needed? We have lots of species living today that we can trace to shared ancestors, like how we can trace humans, chimps, and orangutans to a common ancestor. It's true that speciation happens much faster after an extinction, this makes sense because extinction events cause previously occupied ecological niches to get opened up. In a static environment the rate of change is low because most species will be in a local optimum. Everything we see appears to confirm evolution. If you think the fossil record disproves evolution you should consider if it merely disproves your understanding of evolution, which may be incorrect. > That’s exactly what evolutionists do. These failures of the theory, both observational and historical, would have had it tossed long ago like most theories that fail that much. Instead, they keep making excuses for it or emphasizing again that it must be true. You mean biologists? To call evolution a failed theory is absurd, it's one of the most successful theories science has produced. It's supported by the fossil record, by DNA research, by bacteria becoming resistant to antibiotics and gaining the ability to digest plastics. By vestigial organs. By the way that early fetal development for mammals all looks the same. And there are no counter examples. No species appearing out of nowhere without a historical ancestor. No species with completely incompatible biology to our own. > That’s not science. That is like dogma driven by emotional or socio-political factors. Which also provably exist in institutions promoting it. So, it’s not science since it (a) is driven by non-scientific forces and (b) continues to fail the scientific method. You are seeing a conspiracy where none exists. If you have a better theory than evolution I encourage you to publish, and in a decade or two we will all know you as a Nobel prize winner. Maybe share it with us here on HN, I for one would be delighted to have been one of the first to have read this new theory. I sure hope it doesn't rely on an invisible undetectable magic man steering everything. Even if a theory is invented to supplant evolution, I guarantee it will include evolution. Just like General Relativity supplanted Newtonian Physics, turns out that they have pretty much the same results at the scales and speeds we usually find ourselves at. And just like the Earth being an oblate sphere instead of a perfect sphere. The basic idea of evolution is correct and any hypothetical future changes will be a refinement on what we already know, not a radically different thing. 1. https://en.m.wikipedia.org/wiki/E._coli_long-term_evolution_experiment https://en.m.wikipedia.org/wiki/E._coli_long-term_evolution_... 2. https://evolution.berkeley.edu/evo-news/speciation-in-real-time/ https://evolution.berkeley.edu/evo-news/speciation-in-real-t...