New Species
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New Species
Post #1How different does an organism have to be to be classified as a new organism? Like, on the evolutionary charts, they only name the "major" organisms, but leave the ones along the way unnamed. Like for instance, on this chart I am looking at right now in my biology book, on the bottom fo the tree is the Remote Common Ancestor (early vertebrate). A "branch" is drawn up to the right Recent Common Ancestor (armidillo-like mammal). It branches there once again now into 2 branches. One leads to the Glyptodont. The other one to the Armidillo. Now in this section of the chart alone, only 4 organisms are named, but shouldn't there be millions of forms named instead. Or are the ones along the branches ignored because they are half-half or is it REALLY because evolution is wrong?
Post #11
Naming species different names is classifying them. Our similarity to apes could be chance, just like the Big Bang was chance, and that the primordial soup becoming small organisms is chance, etc. How different do we have to be to be classified differently from our "ancestors"? So what your saying is we classify organisms differently today than from organisms living way back when?
You are right animals change over time, as in microevolution. Macroevolution has not been observed yet. Why could we not classify an organism the same even tho it changes some.
You are right animals change over time, as in microevolution. Macroevolution has not been observed yet. Why could we not classify an organism the same even tho it changes some.
Post #12
No, since adapting to environments is observable. You accept micro-evolution is proven, then you have to accept that we adapt.adherent wrote:Naming species different names is classifying them. Our similarity to apes could be chance, just like the Big Bang was chance, and that the primordial soup becoming small organisms is chance, etc.
We are forced to, since we don't have DNA and can't study biology apart from skeletal structure. Obviously.How different do we have to be to be classified differently from our "ancestors"? So what your saying is we classify organisms differently today than from organisms living way back when?
As I said, we cannot clasify species as the same because we lack the data. We have to rely on other means. If we find two triceratops the same, with one having slightly pointier horns, and both are attributed to roughly the same era, no scientists is going to say, "wow, dude, we just discovered two different species!" You are abandoning practicality.You are right animals change over time, as in microevolution. Macroevolution has not been observed yet. Why could we not classify an organism the same even tho it changes some.
As for macro-evolution not occuring, speciation has been observed. If you would like a list, I can provide one.
<i>'Beauty is truth, truth beauty,—that is all
Ye know on earth, and all ye need to know.'</i>
-John Keats, Ode on a Grecian Urn.
Ye know on earth, and all ye need to know.'</i>
-John Keats, Ode on a Grecian Urn.
Post #13
"We are forced to" is not really that good of a reason and should not even be a reason. And of course we adapt, it doesn't however mean that an organism will change species. Isn't speciation where one species evolves into another? If there were examples of speciation then we would know for sure macroevolution is right. If we can't classify organisms like we do living organisms today, then we shouldn't classify them at all and find another theory that supports classification of both the living and extinct.
Post #14
adherent wrote:"We are forced to" is not really that good of a reason and should not even be a reason. And of course we adapt, it doesn't however mean that an organism will change species. Isn't speciation where one species evolves into another? If there were examples of speciation then we would know for sure macroevolution is right. If we can't classify organisms like we do living organisms today, then we shouldn't classify them at all and find another theory that supports classification of both the living and extinct.
Ah, so evolution is wrong because it doesn't name species like you'd want them to? It's not evolution that decides the names of the species, however. Evolution simply interprets the meaning of these similar fossils from observation and logic, not through semantics arguments.
<i>'Beauty is truth, truth beauty,—that is all
Ye know on earth, and all ye need to know.'</i>
-John Keats, Ode on a Grecian Urn.
Ye know on earth, and all ye need to know.'</i>
-John Keats, Ode on a Grecian Urn.
Post #15
"Like I'd want them to?" nope, they incorrectly name 'em becuase they have a faulty classification system. Well evolution is where one species evolves into another. How do we know its a new species? Arg... you keep ignoring the question: How dominant does a feature have to be for the organism to be a different species from its ancestor?"<-- that points to the evolution of the extinct animals
Post #16
The classification of animals into groups based on similarity is not un-Christian. Linnaeus was a Christian. Classifying animals based on similarity is simply convenient.
The fossil problem is very big. As one paleontologist said in a Discover magazine I once read, "If future scientists discovered the skeletons of Danny DeVito and Arnold Schwarzenegger, they would probably classify them as different species." (Paraphrased; I can't find the exact article, so this is from memory).
When scientists look at the fossils of living things now extinct, they reconstruct them as well as possible and group/name them by similarity because it is convenient to do so. However, there are limits to what one can know based on fossils, so mistakes can easily (and probably often do) happen in classifying species. Even with DNA, we are incapable of observing behavior, which is sometimes the only difference between different species.
Grouping organisms according to how they are "related" makes perfect sense within the evolutionary mindset. Pointing out a problem with evolutionary taxonomy does not hurt the possibility of evolution. The converse, pointing out a problem with evolution will reduce the credibility of the evolutionary models of taxonomy, is true.
The fossil problem is very big. As one paleontologist said in a Discover magazine I once read, "If future scientists discovered the skeletons of Danny DeVito and Arnold Schwarzenegger, they would probably classify them as different species." (Paraphrased; I can't find the exact article, so this is from memory).
When scientists look at the fossils of living things now extinct, they reconstruct them as well as possible and group/name them by similarity because it is convenient to do so. However, there are limits to what one can know based on fossils, so mistakes can easily (and probably often do) happen in classifying species. Even with DNA, we are incapable of observing behavior, which is sometimes the only difference between different species.
Grouping organisms according to how they are "related" makes perfect sense within the evolutionary mindset. Pointing out a problem with evolutionary taxonomy does not hurt the possibility of evolution. The converse, pointing out a problem with evolution will reduce the credibility of the evolutionary models of taxonomy, is true.
Post #17
The reason species are so confusing is entirely our own faults. A "species" is not something real in nature, but a concept that we humans try to force onto biodiversity in order to help us make sense of things.
This causes all sorts of problems, because biology isn't kind to the human desire to label and neatly categorise everything: it's messy, full of grey areas and exceptions to rules, and everything that seems solid turns to sand in your grasp at the margins. Until you're used to it, this is very disorienting for anyone who wants to find objective lines in the dirt. It feels unscientific, because science books are full of definitions and classifications to the extent that it feels like anything we can't objectively pigeonhole is a failure.
Species definitions are one area where this is felt acutely. First, there's the distinction between cladogenesis and anagenesis: Cladogenesis is where one species becomes two separate species, anagenesis is where evolutionary changes add up in a single lineage until the population has changed enough to be classified a new species. The latter seems to be what's causing the problem.
The reason this is a problem is because the Biological Species Concept (BSC, already described in this thread) breaks down. How can you test to see if humans today could breed with humans from 10 000 years ago? You can't, of course, so you can't use that definition of species.
What's worse, that's far from the only case where the BSC breaks down. Other examples abound: The reproductive barriers of plants are far less robust than in most animals, and populations of plants that are really extremely different from one another are known to produce fertile hybrids all the time. Sometimes these interfertile plants are from totally different families!
Ring species, such as the famous arctic herring gulls, are another good example of why an objective species definition is impossible. This is a "species" that lives around the arctic circle, but not inside the circle itself. Where the two ends of the population meet, individuals are reproductively incompatible, and are thus from different species according to the BSC. However, and this is the kicker, the species has an unbroken graduation from one end to the other, so individual A from one end of the species's range could breed with individual B from a few kilometers further around the circle, who could breed with individual C even further around, and so forth. If you wiped out a section of the population, you'd suddenly have two incompatible populations. So, this demonstrates the subjective nature of species classifications in general. It's an artificial category imposed on a far more complex reality for our own convenience, and no-one should be suprised if any given definition has exceptions.
Paleontology, to actually come to the point (sorry for rambling), is yet another exception to the biological species concept. You can't test to see if any two dinosaur fossils could interbreed because, being nothing but stone casts of old skeletons, they lack the necessary reproductive equipment to carry out such an experiment
. Hence, one of the major things paleontologists do with their time is argue with each other about what fossils are what species, and what to call that jawbone, and which skulls are related to which other skulls. It's called phylogenetic systematics, which is the attempt to discover the evolutionary relationships of organisms (be they represented by living or dead specimens) and classification is only one part of it. Paleontologists apply a variety of complicated methodologies to try and answer the question that adherent is posing here. For a simple example, if we have a hundred fossils that are all pretty similar, and we find one more that is similar, but differs significantly in some feature, paleontologists can carefully measure critical anatomical features to see if the new specimen lies outside the range of variation in the other specimens. If it does, it can be considered statistically likely that the specimen comes from a different population from all the others.
Hmm. I think I have rattled on for a bit long. I'll leave it at that, lest I enthuse too copiously and induce comas.
Yours
-Timothy.
This causes all sorts of problems, because biology isn't kind to the human desire to label and neatly categorise everything: it's messy, full of grey areas and exceptions to rules, and everything that seems solid turns to sand in your grasp at the margins. Until you're used to it, this is very disorienting for anyone who wants to find objective lines in the dirt. It feels unscientific, because science books are full of definitions and classifications to the extent that it feels like anything we can't objectively pigeonhole is a failure.
Species definitions are one area where this is felt acutely. First, there's the distinction between cladogenesis and anagenesis: Cladogenesis is where one species becomes two separate species, anagenesis is where evolutionary changes add up in a single lineage until the population has changed enough to be classified a new species. The latter seems to be what's causing the problem.
The reason this is a problem is because the Biological Species Concept (BSC, already described in this thread) breaks down. How can you test to see if humans today could breed with humans from 10 000 years ago? You can't, of course, so you can't use that definition of species.
What's worse, that's far from the only case where the BSC breaks down. Other examples abound: The reproductive barriers of plants are far less robust than in most animals, and populations of plants that are really extremely different from one another are known to produce fertile hybrids all the time. Sometimes these interfertile plants are from totally different families!
Ring species, such as the famous arctic herring gulls, are another good example of why an objective species definition is impossible. This is a "species" that lives around the arctic circle, but not inside the circle itself. Where the two ends of the population meet, individuals are reproductively incompatible, and are thus from different species according to the BSC. However, and this is the kicker, the species has an unbroken graduation from one end to the other, so individual A from one end of the species's range could breed with individual B from a few kilometers further around the circle, who could breed with individual C even further around, and so forth. If you wiped out a section of the population, you'd suddenly have two incompatible populations. So, this demonstrates the subjective nature of species classifications in general. It's an artificial category imposed on a far more complex reality for our own convenience, and no-one should be suprised if any given definition has exceptions.
Paleontology, to actually come to the point (sorry for rambling), is yet another exception to the biological species concept. You can't test to see if any two dinosaur fossils could interbreed because, being nothing but stone casts of old skeletons, they lack the necessary reproductive equipment to carry out such an experiment
. Hence, one of the major things paleontologists do with their time is argue with each other about what fossils are what species, and what to call that jawbone, and which skulls are related to which other skulls. It's called phylogenetic systematics, which is the attempt to discover the evolutionary relationships of organisms (be they represented by living or dead specimens) and classification is only one part of it. Paleontologists apply a variety of complicated methodologies to try and answer the question that adherent is posing here. For a simple example, if we have a hundred fossils that are all pretty similar, and we find one more that is similar, but differs significantly in some feature, paleontologists can carefully measure critical anatomical features to see if the new specimen lies outside the range of variation in the other specimens. If it does, it can be considered statistically likely that the specimen comes from a different population from all the others. Hmm. I think I have rattled on for a bit long. I'll leave it at that, lest I enthuse too copiously and induce comas.
Yours
-Timothy.
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Oolon Colluphid
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Post #18
Hmmm. Well, speciation has been observed, but creationists claim that it's just within the 'kind' (AiG even goes as far as to claim that rapid speciation is part of the creation model). So, if speciation isn't really macroevolution, we need to know what would count. If it is one 'kind' turning into another, we need a definition of 'kinds'.
So to check if 'kinds' really are immutable, we have to know what a 'kind' is. Would any kind creationist here like to hazard a guess please? It's not species... so is it genus, family, order, class... or something else?
Note that 'baraminologist' Kurt Wise thinks that it is approximately 'family', as with bovidae, felidae etc.
Any takers?
Cheers, Oolon
So to check if 'kinds' really are immutable, we have to know what a 'kind' is. Would any kind
creationist here like to hazard a guess please? It's not species... so is it genus, family, order, class... or something else?Note that 'baraminologist' Kurt Wise thinks that it is approximately 'family', as with bovidae, felidae etc.
Any takers?
Cheers, Oolon
