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Junior Member (Idle past 2688 days) Posts: 7 From: South Africa Joined: |
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Author | Topic: Extent of Mutational Capability | ||||||||||||||||||||||||||||||||||||||||||||
Pressie Member Posts: 2103 From: Pretoria, SA Joined: |
Yada, Yada, Yada.
Word salads. All the emprical, verifiable evidence from all over the world show that the first form of life as we know it were some forms of prokaryotes.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
... So cladistics does not test to determine IF they are related but rather HOW they are related. This cladogram is then the hypothesis as to how the organisms are related and possibly how a particular character has evolved. I would say "HOW they could be related" -- as you say it is an hypothesis.
IF there were no common markers then you could not develop a cladogram ... Enjoy Edited by RAZD, : iby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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Tangle Member Posts: 9512 From: UK Joined: Member Rating: 4.8 |
RAZD writes: You can also throw Homo neanderthalus in the mix as sister species in clade Homo, closer to H.sapiens than the Pan clade. This is where it gets messy, Neanderthals are now - along with at least 4 other human forms mostly classed as sub-species of Homo sapiens. They can't be species as they interbred. H. sapiens sapiens seems to be a bit of a mongrel. This has all changed since I formally studied it.Je suis Charlie. Je suis Ahmed. Je suis Juif. Je suis Parisien. Life, don't talk to me about life - Marvin the Paranoid Android "Science adjusts it's views based on what's observed.Faith is the denial of observation so that Belief can be preserved." - Tim Minchin, in his beat poem, Storm.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
This is where it gets messy, Neanderthals are now - along with at least 4 other human forms mostly classed as sub-species of Homo sapiens. ... Yeah, I'll accept that, the braided pattern on Peter & Rosemary Grant, Darwin's Finches and Evolution and Interweaving Evolution & Hybrid Vigor quote: Enjoyby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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Tangle Member Posts: 9512 From: UK Joined: Member Rating: 4.8 |
RAZD writes: Where C is not the same as A, but is a braided mosaic of B and D. Note that A, B, C and D still form a clade descended from A. Sort of but in the homo genus it seems that B, interbred with C,D, E and F. And C interbred with D & E but not F and so on depending who travelled where. All 5 sub-species co-existed and as late as 40,000 years ago. It makes you wonder whether all/most species whilst they're in the process of speciation meet up breed, move away, meet again etc etc and either finally separate for good like lions and tigers but can in principal interbreed or one outcompetes the others - as H. sapiens sapiens. I feels a little like horizontal gene transfer. Life is messy.Je suis Charlie. Je suis Ahmed. Je suis Juif. Je suis Parisien. Life, don't talk to me about life - Marvin the Paranoid Android "Science adjusts it's views based on what's observed.Faith is the denial of observation so that Belief can be preserved." - Tim Minchin, in his beat poem, Storm.
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dwise1 Member Posts: 5952 Joined: Member Rating: 5.2
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Greg, what is your background with this "creationism-vs-evolution debate"?
The first thing you should know is that "creation science" itself is a deliberately crafted legalistic deception. For most of the 20th century (circa 1920 to 1968, during which the "monkey laws" were in effect), anti-evolutionists could be open about having purely religious reasons for opposing the teaching of evolution in the schools. But then Epperson v. Arkansas (1968) led to the striking down of the "monkey laws" and after a few failed attempts the anti-evolutionists learned that the courts no longer allowed them to ban evolution for religious reasons. In response, they superficially scrubbed their published materials of all explicit references to the Bible and to God (who suddenly became an "unnamed generic Creator") and dishonestly claimed (ie, lied) to the courts that their objection to evolution was for "purely scientific reasons." That is traditionally known as their playing the game of "Hide the Bible." That deception was exposed in Edwards v. Aguillard (1987), whereupon the anti-evolutionists switched to playing the game of "Hide the Creationism" by calling it "intelligent design" instead of "creation science." "Creation science" is based on their "Two Model Approach", in which they "define" two "mutually exclusive models", the "creation model" and the "evolution model", and then set about attacking their "evolution model" and proclaiming that that proves their "creation model" without ever having to present, support, or defend that "model" -- in fact, repeatedly in creationist-run debates the creationists steadfastly refuse any discussion of their "creation model". Here is how Dr. Henry Morris, one of the Founding Fathers of "Creation Science", described the "Two Model Approach" to me (my emphasis added):
quote:In reality, the "creation model" is very highly restricted to young-earth creationism, which results in the vast majority of theistic creationist ideas (including most Christian ideas about Creation) being lumped into the "only alternative", their "atheistic" "evolution model." So of course they never dare to present or discuss their "creation model", since that would expose their game of "Hide the Bible." The other consequence of the "Two Model Approach" is that their "evolution model" has virtually nothing at all to do with evolution. At best, it is a caricature misrepresentation of evolution, a strawman for creationists to attack and crow about having defeated while steering clear of actual evolution itself. You yourself presented one such misrepresentation of evolution, also echoed by CRR: the idea that evolution would require animals "evolving from one kind to another", such as a cat "evolving" into a dog (even though from the cat's perspective that would be devolving). As I and others here have described, not only does evolution not say or require that but such an event would be completely contrary to evolution. So when a creationist "disproves" evolution by pointing out that we never see a cat evolving into a dog, he is actually lying to you. The approach you're taking in your year-old investigation appears to be one of collecting what both sides have to say. You are apparently treating what you collect as being different interpretations of the evidence (a commonly expressed creationist position and argument). But that cannot work when one side (the creationists) bases its "interpretations" on a misrepresentation of the other side. It would be like someone "disproving" Christianity by misrepresenting Communion as being nothing but cannabalism. Or "true Christians" redefining what Christianity is in order to claim that Catholics are not Christians -- a friend listens regularly to The Jesus Christ Show and it really gets Jesus angry whenever he hears that nonsense about Catholics not being Christians. So part of your investigation also needs to pay attention to whether both sides are being honest and truthful in what they say about the other side. In particular, are creationists being honest and truthful about how they represent evolution? Or are they misrepresenting it in order to turn it into a strawman thus deceiving you and themselves?
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Dr Adequate Member (Idle past 313 days) Posts: 16113 Joined: |
You can also throw Homo neanderthalus in the mix as sister species in clade Homo, closer to H.sapiens than the Pan clade. I specifically said "living organisms". Of course, it would indeed also be true if I'd said all species living or dead, but that wouldn't be testable, so it wouldn't be a testable prediction of the theory of evolution.
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dwise1 Member Posts: 5952 Joined: Member Rating: 5.2 |
It makes you wonder whether all/most species whilst they're in the process of speciation meet up breed, move away, meet again etc etc and either finally separate for good like lions and tigers but can in principal interbreed or one outcompetes the others That interbreeding happens a lot. A number of examples of canine hybrids and feline hybrids happen in the wild -- see my Message 9 for links. And a local creationist seems to love his "chicken or the egg" argument in which his answer is "two chickens", but they need to completely re-evolve their reproductive systems simultaneously, or so he claims (it makes absolutely no sense to me either). In reality, chickens (Gallus gallus domesticus) are still able to interbreed with their ancestral species, the red jungle fowl (Gallus gallus), such that it's now very difficult to find a red jungle fowl that is not a chicken hybrid (https://en.wikipedia.org/wiki/Red_junglefowl#Hybridisation). Yes, life can be very messy. Edited by dwise1, : "to find" and added a Wikipedia link
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Taq Member Posts: 10084 Joined: Member Rating: 5.1 |
Tangle writes: This is where it gets messy, Neanderthals are now - along with at least 4 other human forms mostly classed as sub-species of Homo sapiens. They can't be species as they interbred. Since speciation is not a binary event we can expect limited interbreeding during speciation for many populations. Whether we decide to call them separate species or subspecies does nothing to change the reality. The map is not the territory, as the old saying goes. What we do have is genetically distinct populations that did occasionally interbreed. What produced genetically distinct populations was a lack of free interbreeding between the populations, also known as speciation.
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Tangle Member Posts: 9512 From: UK Joined: Member Rating: 4.8 |
Taq writes: What we do have is genetically distinct populations that did occasionally interbreed. I wonder how distinct? "Neanderthal genetic differences to humans must therefore be interpreted within the context of human diversity." Neanderthal genome project - Wikipedia Our DNA is >99% the same as neanderthal but then again so are chimps....Je suis Charlie. Je suis Ahmed. Je suis Juif. Je suis Parisien. Life, don't talk to me about life - Marvin the Paranoid Android "Science adjusts it's views based on what's observed.Faith is the denial of observation so that Belief can be preserved." - Tim Minchin, in his beat poem, Storm.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
It makes you wonder whether all/most species whilst they're in the process of speciation meet up breed, move away, meet again etc etc and either finally separate for good like lions and tigers but can in principal interbreed or one outcompetes the others - as H. sapiens sapiens. Indeed, when llamas and camels can be bred it shows that genetic reproductive isolation does not always occur as populations diverge over time, and the ability to breed may survive thousands of years while populations spread to opposite sides of the globe. I remember a study of stickleback minnows done when I was at uni, and it showed that the hornier the male sticklebacks were, the more likely they were to attempt breeding with things that looked less and less like female stickleback minnows, ultimately trying to mate with a twig. This could be part of how biology encourages mating. When we look at the fossil record for Pelycodus we see some arbitrary species designations (linear speciation) and one speciation event dividing the breeding population into two separate populations.
The area between depths 1200 and 1400 could be a braided interaction period, where packs would divide, meet up, divide again, depending on ecological changes (droughts, floods, normal weather, etc) Were they fully reproductively isolated when they did finally divide for good? Or did they just move into different habitates and never met up again? Enjoyby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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Taq Member Posts: 10084 Joined: Member Rating: 5.1
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Tangle writes: I wonder how distinct? "Neanderthal genetic differences to humans must therefore be interpreted within the context of human diversity."
The question I often ask in return is how do they know that 5% of the modern human genome is made up of Neanderthal DNA? How do they tell the difference between Neanderthal DNA and modern human DNA? The answer is pretty simple. It's different. Not only is it different now, it was different then. I can't seem to find it now, but if memory serves they found an ancient (25,000 years old?) modern human fossil and were able to extract mitochondrial DNA. The mtDNA from the ancient modern human closely matched that of living modern humans. Neanderthal mtDNA does not.
green is modern human v. modern human, red is modern human v. Neanderthal, blue is modern human v. chimp [these are values for living modern humans and Neanderthals] I think it is also worth mentioning that these Neanderthals were identified by morphology. If this were just a case of a diverse modern human population, then why the correlation between the very different mtDNA and the very different morphology? The best answer, IMHO, is that they were separate species. Edited by Taq, : No reason given. Edited by Taq, : No reason given.
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Pressie Member Posts: 2103 From: Pretoria, SA Joined: |
Taq writes: Great explanation. I'd like to add that not all humans have Neanderthal DNA. Remains of Neanderthal genomes are found in Europeans and East Asians for example, but people of Sub-Sahara African ancestry don't have those genes. The question I often ask in return is how do they know that 5% of the modern human genome is made up of Neanderthal DNA?... Scientists Identify Neanderthal Genes in Modern Human DNA | Anthropology | Sci-News.com First part:
In two new studies, genetic researchers have shown that about 20 percent of the Neanderthal genome survives in modern humans of non-African ancestry and identified exactly which areas of the human genome retain segments of Neanderthal DNA. So, they know exactly where to look for remains of the Neanderthal genome in humans. Edited by Pressie, : No reason given. Edited by Pressie, : No reason given. Edited by Pressie, : No reason given. Edited by Pressie, : No reason given.
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Tangle Member Posts: 9512 From: UK Joined: Member Rating: 4.8 |
Taq writes: The best answer, IMHO, is that they were separate species. But at that level, the term 'species' doesn't really mean much. A great dane and a shitzu could reasonably be called morphologically different species and I doubt they could breed naturally...... but we have them as the same species. Sapiens and Neanderthal's lived together and sucessfully mated - for thousands of years. It looks like Neadethals could speak - they certainly used tools, drew art, had clothing and ornaments. I suspect if they were living with us now, we'd call them human - in the general usage of that word and science might not even classify them as a subspecies. But who knows, it's all pretty interesting though.Je suis Charlie. Je suis Ahmed. Je suis Juif. Je suis Parisien. "Life, don't talk to me about life" - Marvin the Paranoid Android "Science adjusts it's views based on what's observed.Faith is the denial of observation so that Belief can be preserved." - Tim Minchin, in his beat poem, Storm.
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Taq Member Posts: 10084 Joined: Member Rating: 5.1 |
Tangle writes: But at that level, the term 'species' doesn't really mean much. Of course it still means something. It means that limited interbreeding is producing statistically significant genetic divergence which can be objectively measured.
A great dane and a shitzu could reasonably be called morphologically different species and I doubt they could breed naturally...... but we have them as the same species. Maybe we shouldn't treat them as separate species.
Sapiens and Neanderthal's lived together and sucessfully mated - for thousands of years. It looks like Neadethals could speak - they certainly used tools, drew art, had clothing and ornaments. I suspect if they were living with us now, we'd call them human - in the general usage of that word and science might not even classify them as a subspecies. But who knows, it's all pretty interesting though. 1. If there was free interbreeding then they would fall into the range of variation for modern humans. They don't. 2. They were recognized as not being anatomically modern humans when we first found them. Time isn't going to change that.
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