Evolution and Speciation
Speciation is the process where a population among a particular species becomes reproductively isolated and because of environmental pressures evolves to become a new and distinct species.
Wiki Video Video
Though there is consensus among scientists about evolution and much of how it operates, speciation is a topic that is continually brought up by proponents of intelligent design(ID) and creationism. I have seen many an ID'er or creationist say that speciation does not occur and therefore macro-evolution cannot occur. As far as I am aware, speciation in the animal kingdom has never been directly observed by scientists. The examples used in most videos and in all the literature I've read(admittedly not much) seem to show what I'd call 'preference speciation' or 'barrier speciation' and not a pure genetic speciation.
For example, Western and Eastern Meadowlarks are considered separate species because they have different mating songs and therefore do not mate. While this is true, if one or the other of these species got the bird flu and managed to confuse a member of the other side to mate with it due to its raspy song, they could in fact produce offspring, and their offspring could produce offspring, and so forth.
So it's easy to see how, with enough time and change, this could potentially lead to genetic speciation, but it will not strike the incredulous believer(ha) as convincing.
So I ask you, do you believe speciation occurs? If yes, why? If no, why not?
Wiki Video Video
Though there is consensus among scientists about evolution and much of how it operates, speciation is a topic that is continually brought up by proponents of intelligent design(ID) and creationism. I have seen many an ID'er or creationist say that speciation does not occur and therefore macro-evolution cannot occur. As far as I am aware, speciation in the animal kingdom has never been directly observed by scientists. The examples used in most videos and in all the literature I've read(admittedly not much) seem to show what I'd call 'preference speciation' or 'barrier speciation' and not a pure genetic speciation.
For example, Western and Eastern Meadowlarks are considered separate species because they have different mating songs and therefore do not mate. While this is true, if one or the other of these species got the bird flu and managed to confuse a member of the other side to mate with it due to its raspy song, they could in fact produce offspring, and their offspring could produce offspring, and so forth.
So it's easy to see how, with enough time and change, this could potentially lead to genetic speciation, but it will not strike the incredulous believer(ha) as convincing.
So I ask you, do you believe speciation occurs? If yes, why? If no, why not?
Comments (52)
Thanks for the link. Do scientists consider viruses to be 'living'? I thought there was some debate over that point. Also, viruses don't reproduce in the same way large multi-cellular organisms do, so does that not discount the finding?
To be clear, I personally believe speciation occurs. I am trying to find interesting points on both sides of this so that I have more clarity and better explanations for myself and those I speak to about this subject.
Care to take a position?
Religionists of that level don't have anything useful to say about science nor are they worth trying to convince because their group identity is more important to them than being right. This has been studied extensively (see some of the podcasts I've linked to recently which give a good overview of the research ) and the results are as bleak as that. The best thing to do is to just leave them to their ignorance. Yes, speciation obviously happens otherwise there wouldn't be any different... species. And how it happens has been studied and described by scientists. It's not a mystery.
What? No. Obviously not. And no, speciation isn't the problem to me, here. It's the "believe" part. I don't see how hypotheses and/or theories require belief. Then again, I'm one of those people who distinguishes between conjecture and dogmatism. So. To be perfectly clear: Do I think speciation is a thing? Sure. Am I willing to chuck the notion in light of counter evidence? Uh, yes. Do I think that such counter evidence is likely to surface? No.
From memory, there are very obvious (and instantaneous) cases of speciation in plants, through chromosomes reconfiguration. It is probably the clearest example to provide to a recalcitrant non-speciacionist.
(And if the claim that chromosome reconfiguration is not "true speciation" somehow, remind them that they are cheating, since the layman's idea of "a species" has nothing to do with genotypes; it is about morphology).
Of course, the problem with that is that we have to live with these "ignorant" people. Govern our society together. Live next door to each other. There have been plenty of discussions on the forum about how a rigid reductionist "scientific" view of the world warps an understanding of how the world works.
There is a body of knowledge which is relevant here. Groups of the same species that are separated geographically they can mate with groups near to them, but a sort of chain is formed in which the groups at the most extreme ends of the chain can no longer mate. There is a name for this, sadly I cannot recall what that is.
So, what is the evidence for speciation? Not viruses, not unusual plant behavior, just regular organisms evolving from one species to another. 1) fossil record. 2) comparative genetic studies between organisms 3) experience with breeding 4) observations in nature 5) What else?
https://en.wikipedia.org/wiki/Ring_species
It's no more rigid or reductionist to ignore the talking-snake crowd than it is to ignore the flat-earth crowd when it comes to science. They have zero to bring to the table and indulging them serves no purpose. And maybe you have to live next door to them, but most of us don't. In terms of developed countries, they're almost exclusively an American phenomenon. That being the case, you should know that what really warps an understanding of science, and can potentially destroy it, especially among the young, is giving these people a platform that leads to political influence, particularly over educational policy. They won't be given a similar platform here in the science category to spread pseudoscientific nonsense. Again, that has nothing to do with scientism or scientific reductionism. Philosophy and science itself are perfectly valid means to criticize the prevailing scientific orthodoxy.
I think that shows your rigidity and lack of understanding rather than any fault in religious people. You can't separate science from the rest of society.
Quoting Baden
So, let's exclude a large portion of the electorate because we don't agree with their understanding of the world.
Quoting Baden
Where did that come from? There is no discussion here about what should be allowed on the forum. @ProbablyTrue has expressed an interest in interacting with these troglodytes you have such disdain for. Maybe evolution denial is not welcome here, but how to talk to evolution deniers and how to understand what we think is true about evolution should be.
I'm not talking about religious people in general, I'm talking about religious people who maintain that their religious beliefs have a scientific grounding or who try to enforce their religious views re science in the education system, which can only result in mass levels of ignorance, and is a form of abuse as far as I'm concerned.
Quoting T Clark
I don't know exactly what you mean by this. On some level, it's trivially true, but science is the remit of scientists just like engineering is the remit of engineers. I'm not going to go tell an engineer how to build a bridge on the basis of my religious beliefs, or lack thereof, and if I did, he shouldn't listen to me, or we'd have a lot more cars in rivers.
Quoting T Clark
It's not about agreement because there is no debate. The fact is that the Bible is not going to help in any way in understanding evolution. If you can't get that far, then you are not doing science to start with. You're still doing religion. So, yes, let's absolutely exclude them from this area because they have nothing of relevance to say. (In a conversation concerning morality, or theology or philosophy or even science if they are willing to keep religion out of it, that doesn't hold, of course).
Quoting T Clark
I'm just making it clear that we don't want pseudoscience (e.g. so called "ID" or creation science) in the science category. I'm not referring to anyone here, specifically, religious or otherwise. There are lots of ways to criticize evolutionary theory without going that route. We're not at the end of the road with evolution, we simply have a theory, which can and should be criticized, but not on the basis that it contradicts some group's holy book. That's just not the right way to go about things in this field.
Quoting Science News
BLACK AND WHITE As soot settled onto trees in Britain during the Industrial Revolution, a black version of the peppered moth (right) started to overtake the mottled-wing form (left). Scientists have now found the mutation that caused the color shift in a gene called cortex.
Is that really speciation? Can the different varieties interbreed? Do they? Are they present in the same populations, areas?
All dogs are considered the same species, right? Even with very significant differences in form, size, and color.
The burden of proof is really upon those who dispute speciation. (And it becomes a really big burden when we consider that speciation has been observed in many different contexts; "X cannot happen" is a tough proposition to defend when X is all around you).
It wouldn’t be yet. But given an environmental obstruction between the two variants, eventually further biological evolution would bring about two species that won’t interbreed, either for genetic or behavioral reasons. Two examples: Galapagos finches and new world finches (yes, there are more species than the just mentioned); chimps and bonobos.
Edit: this being just one scenario in which specification [doubleedit for the typomister: otherwise known as speciation] would occur.
I think I remember from somewhere that, for large mammals, there has to be 200,000 years of separation before populations will no longer be able to interbreed? Has anyone else heard that.
Also - It is believed that homo sapiens interbred with both Neanderthals and Denisovans and that some of us share genetic material from them.
Don't know about the first issue you bring up. But with this one ... one professor during my university days said that given our genetic similarity it is nearly indisputable that one can have a human-chimp offspring, only that whether or not this offspring would itself be able to reproduce is unknown .... think of mules here (and who in their right minds would even want to find out empirically) ... paraphrasing all this, obviously. Homo sapiens could have genetically interbred with Neanderthals; whether or not the two species (/variants?) interbred despite behavioral differences is in a good deal of dispute from what I know. New info on this is always of interest, though.
It has been reported that Neanderthal genetic material shows signs of homo sapien DNA and vise versa. At one point I guess that was controversial, but I think it has been resolved. Maybe someone can confirm or refute.
No, it's been tried and it didn't work.
https://en.wikipedia.org/wiki/Humanzee
It does. E.g.:
https://news.nationalgeographic.com/news/2010/05/100506-science-neanderthals-humans-mated-interbred-dna-gene/
I had heard that there had been some alternative scenarios proposed for how the DNA got where it is e.g. Neanderthals and humans having a common African ancestor.
The vast majority of the evidence seems to be on the side of interbreeding. E.g:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4947341/ (Full paper)
https://www.nature.com/articles/nature12961 (Abstract)
There is also this that mentions the other hypothesis but comes down on the side on intebreeding anyway:
http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1002947 (Full paper)
from the article:
Quoting wikipedia page
1920's might not have been as advanced in artificial insemination as 1980's; I won't push the issue though. I'd like what you've said to be conclusive and this quoted account to have been a hoax. Still, in one way it makes my hairs stand up that humans have tried this, in another way nothing shocking ... given our capacities for amorality, to put it nicely (as thought the life that would've been birthed could then be dispensed away with after birth ... interesting)
Unfortunately, scientists have historically carried out gruesome experiments on humans that make this kind of thing look relatively mild. I think it's safe to assume pretty much everything has been tried (and will continue to be though some of it covertly to be sure).
Thanks.
To me, you're missing a crucial term here: some. To lump all scientist together like this is might be a disservice to scientists as a whole. Akin to: humans have historically .... you know what, I won't even mention examples. Linguistic gripe, that's all.
Fair point.
But it only takes "some" scientists to ensure that everything that can be studied by science will be. If there really is any danger from AI taking over or genetic catastrophes, some scientist somewhere will go ahead with it anyway. If there really had been a significant chance that the CERN collider could cause a black hole that would consume the Earth, someone would have done it anyway.
I’ve got a better one: organic-molecule nano-technology robots that make use of nucleic acids in combination with proteins … make these “robots” complex enough so that they actually do meaningful things and eventually they will biologically evolve due to mutations (Jurassic Park at the micro reality level). A simple understanding of evolution at the molecular level will attest to this. Un-seeable little robots mutating and replicating worldwide and doing things around and within our bodies … what a thought. And it’s not currently sci-fi touted as science … as is strong AI. Nano-technology research is very sexy, meaning it get's lots of cash from corporations and governments, and we progress in field at a good rate.
Here’s the example that came to mind which I didn’t want to give:Akin to: humans have historically made bets on the sex of third-trimester fetuses and have slashed the pregnant women’s stomach in laughter with knives so as to find out who will win the bet (to me, this is yet a relatively mild example compared to other war atrocities … to not even get into the latter portions of the Roman Coliseum days ) … and humans always will, regardless.
Some humans have historically done this … and the fatalism to “always will because it is in our genetic/God-given nature to” doesn’t sit well with me.
Yes, some humans are a mixture of psychopath and suicidal, and some of these humans happen to be in positions of science. Still, we’re better than animals because … remind me again. Something about forethought, wasn’t it?
Digressing form the topic of the thread, but I thought its worth mentioning.
What’s us with all the fatalism about human behavior anyway? As though life can’t evolve. My take at least.
Denisovans interbred primarily with Asian H.S., while neanderthals interbred with European H.S.
"Yes, Virginia, you actually are a bit of a neanderthal."
They aren't separate species, as far as I know -- not enough time has elapsed. And as is the case of dogs, the number of genes involved in the moth's difference in color is one lousy gene. The wide array of dog shapes and sizes is likewise controlled by one or two genes (which I guess activate other genes). Foxes become tame, with more barking in adults and more upright tail waving, simply because a stress hormone gene is suppressed in the taming. (Tails go up, ears come down. The tame foxes aren't a different species either -- their just tame foxes.
They wouldn't be more dog like until they passed on the gene suppression to their offspring over many generations. How stable the gene suppression is, don't know. The gene suppression that tamed the foxes also ruined their fur for trade purposes.
I saw a documentary about that. It was fascinating. To think that as simple a thing as selecting for tameness could lead to an array of significant body changes. Shows the silliness of reductionist behavioral Darwinism.
Cool.
Haven't been keeping up with the research on this. So its nice to know. Personally, I most associate Neanderthals with "those who threw flowers into the graves of their deceased" ... seems to be a wide spread practice nowadays. :wink:
Which behaviors are in our genes isn't entirely clear, but certainly some fairly socially unattractive features are bred in the bone. Homo Sapiens have a tremendous potential to be really awful, and frequently are. BUT, we also have tremendous potential to be really splendid, and we also are -- fairly often at least. Some goodness is genetic, some badness is genetic, and a lot of it is mediated by culture. For instance, the marines (a cultural institution) build soldiers by overcoming biological and cultural resistance to following orders implicitly through thorough-going training.
Convents, religious orders like the Jesuits, monasteries, and the like also overcome biological and cultural drives to create nuns, monks, and priests. Boarding schools, residential colleges, prisons, and the like also shape behavior by thorough-going training. (No institution, of course, is always successful.)
Right. The neanderthals were not the clod-kicking club carrying characters of cartoons. They engaged in aesthetic activity (ochre coloring and holes added to sea shells) and were capable of kindness. There is a skeleton of either a very early homo sapiens or neanderthal who was quite deformed, but who reached adulthood. He would have had to have been cared for to survive, and survive he did, apparently well cared for.
Not so clear cut:
http://www.macroevolution.net/bonobo-chimpanzee-hybrids.html
https://evolutionnews.org/2014/03/nature_galapago/
Eha, I'd argue that we are the most behaviorally plastic species on earth. The only genetic component to ethics, for me, would be our innate self-interest in warmth, more non-phyisical than physical, with which we're birthed. Then, via interaction, we gain methods/heuristics with which to best safeguard this warmth--from utter selfishness to the opposite tendency.
Its why I don't uphold a position of fatalism as concerns our mores.
Quoting Bitter Crank
Very interesting.
Quoting Janus
Akin to what does and doesn't get added to posts, the very notion of species isn't clear cut to begin with. What to do?
True enough, and if the very notion of species is not clear cut then the notion of speciation would be all the less so.
Man, there some degree of uncertainty everywhere if you look for it intently enough. We do our best to map out the reality we live in all the same. There is no doubt that a bacteria is a different species from a human, cat from dog from bear, etc. even though they all branched out from common ancestors. (not here entertaining biological evolution deniers)
Will be logging out for the day ...
It's true there are different species, and the evidence certainly appears to show that evolution (in the sense of a changing and progressive series of more or less related plant and animal species) has occurred; the rest is conjecture.
Quoting Baden
Quoting T Clark
Quoting Baden
I do have an interest in debating these things with some religious people, more specifically, religious people that make up my family and friends. I'm fully aware that a committed ID'er or a creationist will not be convinced by almost any evidence; as you said Baden, it's a group identity thing. However, your run-of-the-mill religious person who has yet to be convinced of the full scope of evolution lives off the scraps of the ideologues. I should know too: I was brought up as a young earth creationist.
It's not necessarily an attempt to disabuse these people of their religious beliefs(the evangelist in me can't help but try), but rather an attempt to help them correct their scientific misunderstanding so that their religious belief at least conforms to reality.
Quoting T Clark
I think 1-4 make a compelling case on their own, and when you add viruses and plants to the equation it bolsters that case. When one steps back and takes into account cosmological timelines, geological timelines, and all of the above, it paints a fairly holistic picture that is hard to make sense of with any other description.
Fair points. I've had some exhausting experiences debating creationists and the like and seen many others suffer the same fate, so my attitude is somewhat jaded.
The percentages of success are dismally low, but it does happen from time to time. Worked for me anyway.
:up:
Well, I do think the idea of geographical isolation is the most (and perhaps the only) plausible explanation we can presently come up with for the observed (in fossil remains) progression of special changes.
As we discussed in the Shoutbox, the fact that the person you are trying to have this discussion with already is open to the idea of cosmological/geological time is half the journey. I think that's a much bigger conceptual jump than evolution is.
I'm not sure that's true in this case. I think it's easier for people to believe in a grand time scale for the universe than it is for them to accept that they evolved from other species. What's important from his religious perspective is that we are wholly different from other animals. His openness to a cosmic time scale is just a foothold; it doesn't get us all the way up the mountain.
I'm always moved by signs of love among people who are considered less than us. Of course they loved their children, their mothers, their fathers, their husbands, their wives. Of course, of course, of course, of course. Why would we possibly imagine they wouldn't.