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Author | Topic: Is there evidence for macroevolution? | |||||||||||||||||||||||||||
Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
I see you say later on in this thread that you are a mathematician, I suppose that explains your bizzarely hardline approach to 'Scientific Terms'. Perhaps you aren't familiar with Biology but if your line is the correct one then I fear we will have to give up on biology being a science altogether.
TTFN, WK
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Chiroptera Inactive Member |
But I am afraid that it is wasted on me. I never use the words "micro-" or "macroevolution". I could give very precise definitions for them, but I'm not sure that anyone would find my definitions useful, heh.
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Chiroptera Inactive Member |
Is my approach to definitions really so bizarre? Definitions were pretty darned precise when I was studying the physical sciences. I also recall that definitions were pretty precise when I took geology as a college freshman. My high school AP course was quite a while ago, I admit, but I think I recall that the definitions used there were relatively precise.
But maybe, as in my reply to sfs, I am distinguishing between a precise definition being used to describe phenomena that exists in a continuum, whereas you are not? It is possible for a definition to be very precise but there to be situations where it becomes blurred whether the situation fits or does not fit the definition (sfs's example of species); maybe you still count this as an imprecise definition?
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sfs Member (Idle past 2563 days) Posts: 464 From: Cambridge, MA USA Joined: |
Which hard sciences did you study? Biology undoubtedly has looser definitions than physics does -- it's a messier subject. (At least that's my impression, and I've been both a physicist and a biologist.)
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Mission for Truth Inactive Member |
So, to get it straight then. Is Homo Erectus a different species then what we are today, because of it's own unique gene pool? Even though we are so closely related? If so, I can't understand how Cro-Magnon man (being a different species) could walk the streets of L.A. and not be noticed, like people say. My question is, in these two close "look-alike" cases, how could two groups of human be two different groups of species as well? My current view of different species are humans and cats, or giraffes and lions, for example. That, to me, makes sense.
Don't get me wrong though. I believe evolution makes sense and I want to believe it, but I'm obviously not clear on the concepts. However, I don't blame this fault on myself, if evolution is actually true then I think creationists should stop with their "creation science" because to someone like me they seem to make sense (even though it could be one of those ignorant lies), but then again, so do the evolutionists. So, please, help me get my facts together!
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coffee_addict Member (Idle past 506 days) Posts: 3645 From: Indianapolis, IN Joined: |
Mission writes: So, to get it straight then. Is Homo Erectus a different species then what we are today, because of it's own unique gene pool? Even though we are so closely related? If so, I can't understand how Cro-Magnon man (being a different species) could walk the streets of L.A. and not be noticed, like people say. My question is, in these two close "look-alike" cases, how could two groups of human be two different groups of species as well? My current view of different species are humans and cats, or giraffes and lions, for example. That, to me, makes sense. What about tarantulas? Do you believe that they are all the same species? To you people, they all look the same, right? Edited: To be more clear, do you think that the following 2 tarantulas are of the same species?
The answer is NO! The 2 are almost identical in looks. However, they not in the same species. Heck, they're not even in the same genera. If you ever succeed in interbreeding the 2, you will probably get a nobel prize for doing so. Their genetic makeup is just too different to be qualified as the same species. With that said, looks aren't the only thing that constitute a species. If you want to get technical, you have to expand your definition of what constitute as different species. By the way, the top one is a phormictopus atrichomatus and the bottom one is a grammostola alticeps. I know, I'm a tarantula freak. This message has been edited by Lam, 05-05-2004 12:37 AM The Laminator
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Sylas Member (Idle past 5289 days) Posts: 766 From: Newcastle, Australia Joined: |
Mission for Truth writes:
So, to get it straight then. Is Homo Erectus a different species then what we are today, because of it's own unique gene pool? Even though we are so closely related? If so, I can't understand how Cro-Magnon man (being a different species) could walk the streets of L.A. and not be noticed, like people say. Cro Magnon are not a different species. The term refers to a Stone Age culture group; not a species. The Cro Magnons were fully anatomically modern humans. They were weren't even archaic form Homo sapiens; they were basically just like people today, defined by a cultural identification of some kind. This has long been recognized by palaeontologists, and recently confirmed by genetic evidence that puts them slap bang in the middle of the existing human diversity. See:
Evidence for a genetic discontinuity between Neandertals and 24,000-year-old anatomically modern Europeans discussed in more detail at Message 37by D. Caramelli et. al., in PNAS, May 27, 2003, vol. 100, no. 11, pp 6593-6597 My question is, in these two close "look-alike" cases, how could two groups of human be two different groups of species as well? My current view of different species are humans and cats, or giraffes and lions, for example. That, to me, makes sense. The term species is the closest we have to an objectively defined taxonomic rank; and yet even that admits grey areas. For example, is chimpanzee a species? Within chimpanzees, the two main species are Pan troglodytes (common chimpanzee) and Pan paniscus (pygmy chimpanzee, or bonobo). Within the common chimpanzees there are three clearly recognized subspecies: Pan troglodytes troglodytes (central chimpanzee, or black-faced chimpanzee), Pan troglodytes verus (western chimpanzee, masked or pale-faced chimpanzee) and Pan troglodytes schweinfurthii (eastern chimpanzee, long-haired chimpanzee). Recently there has also been identified Pan troglodytes vellerosus (Nigerian chimpanzee) which is the rarest. There have also been hints of another unknown form of giant chimpanzee, as yet unconfirmed, called the "Bondo mystery ape". It is most likely a group of large chimpanzees, but whether it is a new subspecies or not is not known. I believe that all these species of chimpanzee are actually interfertile, though I am currently waiting on an email from an expert on the subject to confirm this. The groups do not interbreed naturally in the wild (at present?) and conservation efforts seek to maintain this natural diversity in captivity. The term "human" is ambiguous. For example, are Neandertals human? I would say yes; although they were most likely a distinct species, separated by a genetic distinct comparable to that between subspecies of common chimpanzee. This is discussed in Message 6. Similarly, I call Homo erectus human, although they were certainly a different species, and very different to ourselves. I think it may have been Richard Leakey who proposed that the term "human" could reasonable be taken to mean "bipedal ape", which makes the Australopithecines human as well. I'm fine with that; it is not a big issue in the present as the only humans are the one species of Homo sapiens, which is actually very homogeneous genetically speaking, and not able to be divided even into subspecies any reasonable way. Living humans incorporate less genetic diversity than any one of the chimpanzee subspecies, I believe; though I'm still in search of good numbers on that. Basically, the comparatively high genetic homogeneity of living humans indicates to most scientists that there was a significant population bottleneck around 70,000 years ago or so.
Don't get me wrong though. I believe evolution makes sense and I want to believe it, but I'm obviously not clear on the concepts. However, I don't blame this fault on myself, if evolution is actually true then I think creationists should stop with their "creation science" because to someone like me they seem to make sense (even though it could be one of those ignorant lies), but then again, so do the evolutionists. So, please, help me get my facts together! Of course... although getting facts together is not easy. You should continue to read and explore; and not just take the word of anyone uncritically. As you read more, from more sources, you gradually build up a reasonable picture of what is known, and not known (and who makes sense in describing it!) Cheers — Sylas
Edited to emphasise that Homo erectus is a different species to Homo sapiens. Fixed spelling while I was at it. This message has been edited by Sylas, 05-05-2004 01:12 AM
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RAZD Member (Idle past 1434 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Small Correction
Cro Magnon is not a separate species but Homo sapiens You want to go back to Homo heidelbergensis to get to another species, and even then the looks would not be uncharacteristic of many people on earth due to the racial diversity. See: http://www.mnh.si.edu/anthro/humanorigins/ha/sap.htm(from Smithsonian website http://www.mnh.si.edu/anthro/humanorigins/ha/a_tree.html -- you can click on each bar to get details) we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}
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coffee_addict Member (Idle past 506 days) Posts: 3645 From: Indianapolis, IN Joined: |
Sylas writes: Similarly, I call Homo erectus human, althuogh they were certainly very different to ourselves. I think it may have been Richard Leakey who proposed that the term "human" could reasonable be taken to mean "bipedal ape", which makes the Australopithicines human as well. I'm fine with that; it is not a big issue in the present as the only humans are the one species of Homo sapiens, which is actually very homogeneous genetically speaking, and not able to be divided even into subspecies any reasonable way. Nah. I'm more comfortable with keeping the word "human" strictly for homo sapiens and and "hominid" for all bipedal apes. The Laminator
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coffee_addict Member (Idle past 506 days) Posts: 3645 From: Indianapolis, IN Joined: |
RAZD writes: Cro Magnon is not a separate species but Homo sapiens I think he meant different species to the homo erectus... at least that's what it sounds like to me when I read it. The Laminator
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coffee_addict Member (Idle past 506 days) Posts: 3645 From: Indianapolis, IN Joined: |
Never mind. After reading it more carefully, it does sound that he meant cro magnons were of different species than modern man.
The Laminator
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Dr Jack Member Posts: 3514 From: Immigrant in the land of Deutsch Joined: Member Rating: 8.3 |
Jean Paul,
Do you have a reference for that claim? Huh? I don't understand. What do you need a reference for? A luca it's own clear and precise definition. And please don't call me MJ, either Jack, or Mr. Jack will do fine.
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Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
One of the points I was trying to make in my post is that it is not a case of a highly specific definition being used to study a phenomenon occuring along a continuum but that there are in fact several different and competing definitions, some highly specific and some less so.
I simply chose Futuyma's from one amongst many because I happen to like his book and it seemed broad enough to encompass many of the more highly specific definitions. Does the existence of many competing definitions preclude something being a scientific term? If so I fear life itself may have to be excluded. TTFN, WK
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Proboscis Inactive Member |
Hey everybody,
I need some information for a research paper I am writing on the topic of Creation vs. Evolution. I am trying to be as open minded as I can to both sides, but I REALLY need some evidence for macro evolution. If someone could give me about five evidences for macro evolution from the fossil record, then give me a place where I could get some backup for those evidences, that would be great. I have plenty of evidence for Creation, but I would still like it if some other creationists could give me some more evidence too. Thanks! Proboscis
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sidelined Member (Idle past 5937 days) Posts: 3435 From: Edmonton Alberta Canada Joined: |
Proboscis
I wonder if you might rather take in a website devoted to links on the issue at http://www.origins.tv/darwin/eyes.htm
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