How do we define a "new" species.

Here's a question for all you atheist's out there. In the process of evolution, How can you justify that one creature's DNA is different than another?
The whole process of evolution is dependant on the fact that animal's physical characteristics change through adaptation, right? Yet There are HUNDREDS of breeds of dogs that have purposefully had their physical traits selected and changed from the originals. Here's the problem, however, every single breed has the same DNA as the wolves and dingos ect. that they descended from. How? I mean, we can't classify an animal as a new species unless it's DNA is different from it's parents, right? So then, every evolved species on the planet should have the same DNA, right? But we don't! Monkeys and Humans have differing DNA, so then we can't be the "New" species, because no matter how different our physical characteristics are, our DNA has to be the same if we descended from them, right? Wrong? C'mon, guys, give me some imput! If you have an answer to all this, tell me! If not, here's my explanation; God instructed Jesus Christ on how to create the earth. Through the centuries, The Lord placed new species on the land which since they had not evolved from old ones, had differing DNA. Although man can use breeding to get different physical appearences in animals, only the Lord can manage to truly customize a new species. Anybody disagree? Agree?

Thread moved here from the Proposed New Topics forum.

Atheists and evolutionists are two different things. Everybody's DNA is different. Don't you watch CSI? That's how they can catch rapists and stuff from DNA. It's like a fingerprint. Well, no, they don't. If they had the same DNA, they'd look the same as those animals. The only organisms that have identical DNA are identical twins. Right and wrong. The majority of our DNA is the same as that of other apes, like chimpanzees, our closest relative. (Chimps are not monkeys, BTW. Monkeys have tails.) In places, however, our DNA is different, which is why we're not all chimps. Well, since we stimulate the formation of new species all the time in the lab; and since we observe it all the time in the wild, I'd say you were wrong about that.

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In the process of evolution, How can you justify that one creature's DNA is different than another?

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Because we can sequence the DNA, and those sequences are different.

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The whole process of evolution is dependant on the fact that animal's physical characteristics change through adaptation, right?

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No, the whole process is dependent on random mutations and natural selection. These two mechanisms CAUSE characteristics to change over time.

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Yet There are HUNDREDS of breeds of dogs that have purposefully had their physical traits selected and changed from the originals. Here's the problem, however, every single breed has the same DNA as the wolves and dingos ect.

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Umm, no they don't. In sexually reproducing animals, no offspring has the same DNA sequence as it's parents or siblings (barring identical twins which came from the same egg and sperm).

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I mean, we can't classify an animal as a new species unless it's DNA is different from it's parents, right?

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Species are defined as populations, not individuals. Species are defined by a group that interbreeds. Since different dogs interbreed, they are considered to be a single species. Species are not defined by their DNA but by the flow of DNA through each generation. Different species may even be able to produce fertile offspring. However, if they do not produce offspring in the wild, or very rarely do, they are considered different species. Again, it is a question of gene flow, not gene sequence.

Can I ask something then? All animals carry the DNA their parents "flow" to them, right? So if a Chimpanzee is born with a very long tail, and eventually it presents some kind of advantage over it's parents until it's parents can't compete, and then die, is that monkey a different species than it's parents? It has the same DNA that they passed on, doesn't it?
I guess my real question to you guys is, at what point in the family tree, or at what generation gap can you consider a new species born? A human can be born with brown hair while his parents have blonde hair, but he still inherited his DNA from them. Does it mean he is the new and improved super-homo-sapien?

In fact there are several different definitions used of species.To start with the chimp-with-a-tail his DNA would NOT be the same as that governing his parents morphology. Amd in fact he would probably be different enough to be classed as a new species under the "morphological species concept". Which incidentally is the way fossil species are usually classified on the basis that morphology is all a fossil preserves (and not all of that).By the definition more commonly used for living species capable of sexual reproduction (the "biolgical species concept") the chimpanzee-with-a-tail would be part of the same species. That concept is based on interfertility. Isolated populations can easily drift into becoming new species on this basis as in the example of the mosquitoes in the London Tube system.Actually telling the differnece between a subspecies and a true species is quite difficult in the wild. It was only recently recognised that there were two species of African Elephant.
http://news.nationalgeographic.com/.../1217_leeelephant.html

Yes, it has the same DNA "they passed on", but not the "same" DNA as it parents, otherwise there would be no genetic difference that would result in the major morphology difference - the tail. Inherited DNA contains some mistakes (mutations) not present in the parental DNA - if a chimp was born with a tail it would likely be due to a mutation not present in its parents' DNA, since chimps don't normally have tails. I'm not sure what you mean by "generation gap", but a distinction between two species is a failure to interbreed under normal (wild) conditions. Thus, if tailed and normal chimps interbreed, they are one species. If the tail presents some barrier to mating between tailed and normal chimps, even if just behavioral, then a "new species" has likely formed.

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All animals carry the DNA their parents "flow" to them, right?

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Yes and no. The egg and sperm carry half of the parents DNA. Also, during the production of eggs and sperm, errors occur when the DNA is copied resulting in mutations. So the offspring carry a mixture of their parents DNA in addition to mutations not found in either of the parents.

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So if a Chimpanzee is born with a very long tail, and eventually it presents some kind of advantage over it's parents until it's parents can't compete, and then die, is that monkey a different species than it's parents?

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Nope, populations are species, not individuals. If a chimp is born with a tail, that tail must allow the chimp to have more children than chimps without tails in order to be deemed beneficial. As you can imagine, if the tail helps the chimp to gather better food, to be healthier, etc. it will probably also have more children. So, the children may also have this tail, through heredity. These children will also have a better chance of having children. Repeat this process over and over and soon you will find that most of the chimp population now has a tail. However, this is not speciation.

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I guess my real question to you guys is, at what point in the family tree, or at what generation gap can you consider a new species born?

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The production of a new species is a difficult thing to deny, yet it obviously happens (well, to us evos anyway). It is like asking when a hill becomes a mountain. If you put a 10 foot berm and Mt. Everest next to each other it is easy to see the difference. However, there are some hills that look a lot like mountains, and vice versa. Also, species form over time, not all at once. What constitutes a new species and what constitutes two separate living species are very different questions.

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A human can be born with brown hair while his parents have blonde hair, but he still inherited his DNA from them. Does it mean he is the new and improved super-homo-sapien?

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The definition of species has to do with reproduction. If this new human breeds with other humans it is still a human.

I think it would be clearer for LDS if you explain to him the processes that are involved, meiosis, cross-overs, etc. I believe that it would shed some light on LDS's confusion of how the scientific community understand the matter rather than what LDS's preconceived idea of it.LDS's use of the word "flow" is very telling of how limited his knowledge of the subject really is. I think a more precise explanation will help much.Besides, when I was a child I believed that the wedding ring is what's responsible for pregnancy. If you said something like you did to me back then, I would have just assumed you were just making up some stuff.

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Here is something to relieve stress.
Assume that a does not equal b.

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a + b = t
(a + b)(a - b) = t(a - b)
a - b = at - bt
a - at = b - bt
a - at + t/4 = b - bt + t/4
(a - t/2) = (b - t/2)
a - t/2 = b - t/2
a = b
Since all numbers are the same, math is useless.

Quote: "If a chimp is born with a tail, that tail must allow the chimp to have more children than chimps without tails in order to be deemed beneficial."So does every mutation that decided a new species according to the theory of evolution have to have increased the species ability to have children? Then why does the average Human mother only have one child at a time, when other mammals have bigger broods of young and less time of pregnancy? How did people supposedly gain a reproducing edge over monkies and such? Also, people and monkies are not... 'incompatible' in reproducing. So we are still monkies if you are using that definition.This message has been edited by LDSdude, 01-25-2005 15:50 AM

Oh, not to bug you, but where is the icon that allows you to quote past statements? I don't see it on my screen.

I'm curious what leads you to believe this is the case. I'm not familiar with any experiments that resulted in monkey-human hybrids. (maybe you meant "ape"? Like, gorillas? I'm not familiar with any human-gorilla hybrids either.)

LDS, if you press the "peek" button on the bottom right of the text field of anyone, you can see how they do their quote fields. Also I believe the FAQ has instructions on how to use some of the functions.

Natural selection generally favors populations of individuals who can not only have children, but sucessfully raise them to an age at which they can reproduce and have children of their own. One of the reasons there are lots of humans even though we take a long time to reproduce is because we take care of our offspring and make sure they don't die. Other animals don't do this, but instead make up for it by having lots of babies, or by having babies that can fend for themselves.Sea turtles, for example, don't take care of their young. They bury their eggs in the sand and then when the baby turtles hatch most of them get eaten, whether while running to the water or later on. They lay so many eggs though, that they don't have to take care of them to reproduce. If one out of a hundred survives and reproduces, that is good enough for them.

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So does every mutation that decided a new species according to the theory of evolution have to have increased the species ability to have children?

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No. Going back to the tail, the tail might have allowed some of the chimps to live in trees that are not accessible to non-tailed chimps. They will reproduce at the same rate, but in different niches. Speciation occurs when only the tailed chimps mate with each other, and consequently the non-tailed chimps mate with each other. This creates two separate gene pools which may result in large differences in morphology over time.As an analogy, let's look at oral traditions. Let's pretend that a culture had a certain story that was always being told around the campfire. Through migration, this culture split into two tribes that are on opposite sides of a mountain range. The two tribes only rarely talk to each other. Now, what is going to happen to that oral tradition? It is a common human trait to change stories between each telling, or between generations. But since these two tribes don't talk to each other, the changes will be different in each tribe. Over time, the stories will not resemble each other. Names, dates, and plots may change so that they are no longer recognizable as being derived from the same story. This is how isolated gene pools work, by isolating different changes in different gene pools.This message has been edited by Loudmouth, 01-25-2005 17:29 AM