Yes I did. That was me disagreeing.
You didn't understand the point that was being made.
Yes I did. That was me disagreeing.
Totally wrong concepts.
Not only is evolution very slow in most cases (see post 83 thru 131 for an exception) but also by extremely small steps, which very often are lost. Also evolution is never leading to some goal - it is just chance variations in the gene pool some of which help reproduction but the majority hinder it or are neutral.
The genes in an old woman are not counted in the evolution of the gene pool as she is no longer fertile. It is the "reproductively active" gene pool that is slowing changing that is evolution. Death can play a role in this change, but only if it removes the particular genes of an individual who might disproportionally transfer them to the constantly changing distribution of genes in the gene pool.
If all of your genes are quite common in the gene pool your living or dying, even while fertile, is not a significant concern / influence on / the evolution of that gene pool.
No I explained in my answer that your POV about a generation is not important or even well defined. I have no idea what you meant by a generation. Is that some fixed number of years? As a woman can have two separate births in 20 months, perhaps you should define your "generation" as 10 months? Please tell how many years or months you are talking about is a generation for an evolutionary step.The smallest unit of evolutionary change is not a single generation? Don't mind me asking, because you went on some tangent on some random topic, which is not understandable why for my rather logical mind trained for years being an accountant.
I'm not entirely sure by what you mean, but yes, behaviors can definitely influence co-evolution of traits. Domestic dogs, for instance, are very gentle and playful, even as adults, since there has been very strong selection to get rid of any wolf like ferocity in their 10 or 20 thousand year domestication.
Of course, this is all speculation, but there's no reason that some proto-dolphins, with an acute sense of hearing, began to find that if they clicked, they could locate prey easier, navigate under water, etc. Of course, the behavior for discovering clicking would also ultimately be genetic, and this is assuming that our proto-dolphin hung out in groups and was social. Even then, only parts needed to evolve to offer a slight advantage. Extra good hearing, for instance, to navigate under water, could have already been in development. A mutation that allowed the proto-dolphin to generate its own sound source to get a better acoustic map may have been useful.
You are assuming wholes without parts. Hippos, as far as I know, swim blind and without any way to navigate other than blundering around underwater. I could be wrong on this. But you could see how even a proto-echolocation system would be advantageous, given that scenario, yes?
Blacks in America which endured the slave trade endured harsh conditions. It seems as a result their offspring have certain advantages.
Bone density at all skeletal sites was statistically significantly greater in black persons than in white persons
Is this to you an example of behavior influencing genetics? If so how exactly does the DNA change. What is the transmitter here that I'm missing? How does a behavior translate to the genetic level?
We've estimated 25,000 human genes. Are there any genes we've fouond that are confirmed to be behavorial?
You see the Hippo is the perfect example. Eye's front in a predator style. It also comes up for air and spends a certain amount of time above water. It pursues it's prey like a croc, or gator from above water using stealth. To me this is where it may break down. It seems echolation would take a very long time to development.
Echolation seems like a long range sensor or even a probe. Imagine to begin to detect the differences in sound isn't just a ear issue it's a brain issue. You said navigation before. Cold water causes a change in sound especially over extreme distance. I could see the first echolocation being used to guage distances in the ocean but not to see. Of course the closer you get to something the faster the return. It allows you to know what the sound is aswell. To get good at this is a brain function. To become specialized to this is a physical function, the Melon, the phonic lips then of course the "array" that allows the dolphin to gather the sound from almost every direction.
It seems a bit much to ask of an un isolated species but then the ocean is it's own type of isolation. Whales and other sea life use echolocation but it's not as wide spread as I thought. Is there a copious amount of biosonar users?
I'll have to look into it.
No I explained in my answer that your POV about a generation is not important or even well defined. I have no idea what you meant by a generation. Is that some fixed number of years? As a woman can have two separate births in 20 months, perhaps you should define your "generation" as 10 months? Please tell how many years or months you are talking about is a generation for an evolutionary step.
I.e. do your even have any idea about what you are talking about? I think not. I think it is all just nonsense.
Is this to you an example of behavior influencing genetics?
I am becomeing convenced you are a troll as twice now I have told your that the smallest unit of evolurionary chage is not a generation and explainded that you are just posting nonsense as you can not even define what is a "generation" for that term to have any sensible application in a discussion of evloution.I only see discrediting the messenger and not the argument. Are you still denying that the smallest unit of evolutionary change is one generation span? Because it is just textbook knowledge. I just see people jumping on the bandwagon. They see 'friends' discrediting my statements and without thinking they do the same. My definition is exactly that of Darwin. Are you calling him wrong? That's a bit arrogant.
I may be wrong, but do not think this is quite correct, although it has come to mean behavior modifies genes in the Western world. I believe the Lamarckian POV was not so much that behavior modifies the genes or inheritance, but that genes were unimportant -All that was required was the correct environment.You are using Lamarckian concepts here....
Thanks. You are absolutely correct. I work from memory and had merged these two very different POVs into one. Again thanks for correcting me.Billy T I am not referring to Lysenkoism.
http://en.wikipedia.org/wiki/Lysenkoism
I am referring to Lamarck, a one time student of Buffon back in the 1700s in France.
http://en.wikipedia.org/wiki/Lamarck
You are using Lamarkian concepts here. This is like supposing that the giraffe has a longer neck because it reaches to feed. One of the early evolution theories was the notion that traits were modified during the lifetime of the organisms. It was learned that this was not correct. Evolution does not occur to the individual, but to the species.
Tuberculatious evolution does not happen to the individual. It happens to a species.
Since we realize what you are doing with "smallest unit of evolutionary change" why don't you toss out your idea in a clear manner. Accountants can do that well.
I am becomeing convenced you are a troll as twice now I have told your that the smallest unit of evolurionary chage is not a generation and explainded that you are just posting nonsense as you can not even define what is a "generation" for that term to have any sensible application in a discussion of evloution.
I have asked you at least four times to try to define it or at least tell how many years of months you think is a generation for an evolutionary step. You have not, so as I suspected, you can not. Thus, I conclude you are just a troll who just continues to post your nonsense.
After three stikes you are out, so I will not reply more to your trolling on this, until you at leas try to define waht you mean by "generation" that has even the slightest sense as an evloutionary step.
In case you do not even know the form of a definition, I will help you get started:
A generation for use in discussion of evolution is _________ .
The DNA is already changed. Within any given generation of organisms, you'll find a wide degree of variation. Just look at your family- even though you are all closely related, you are all quite different! So some blacks would have had higher bone densities to begin with, and your "behavioral" example would select for those with higher density, so the average density would go up over time.[
Other behaviors that could be selected for would be, for instance, mimicry behaviors. There are many insects and spiders that pretend to be ants, because most birds (a major predator of arthropods) don't like to eat ants. These spiders move like ants- their movement could be described as "antlike behavior". They're very convincing. Unless you get down on your hands and knees, you'd think they were ants! You have to count their legs to realize that they're not in Hexapoda. The evolutionary explanation for how these spiders became such good mimics would be that ancestors that were the best mimics of ants produced the most offspring. And in each subsequent generation, only the best mimics got to pass on genes.
I'm not sure why you would an isolated species. Isolation leads to the loss of traits, not the gain of traits, since isolation tends to remove selective pressures. You seem hung up on the idea that newly evolved traits are handicaps.
You have to remember that even pieces of systems can be immensely beneficial, and that we also tend to have pieces of systems that we don't need that later get used. Eukaryotic genomes are quite large, which leads to a lot of variability. I refer you again to the LTEE:
"In 2008, Lenski and his collaborators reported on a particularly important adaptation that occurred in one of the twelve populations: the bacteria evolved the ability to utilize citrate as a source of energy. Normally, E. coli cannot transport citrate from outside the cell to the cell interior (where it could be incorporated into the citric acid cycle); the lack of citrate transport is considered a defining characteristic of the species. Around generation 33,127, the experimenters noticed a dramatically expanded population-size in one of the samples; they found that this population could grow on the excess citrate in the growth medium. They found that the ability to use citrate could spontaneously (although rarely) appear in cultures replicated from earlier frozen samples of that population, from before the citrate mutation appeared, but not in the other 11 populations or in samples before generation 20,000. According to the authors of the study, this suggests that the mutation depends on an earlier, perhaps non-adaptive, change—and more generally (following the argument of Stephen Jay Gould) "that historical contingency can have a profound and lasting impact" on the course of evolution.[4]"
Wikipedia has only mammals listed as echolocaters: cetaceans, bats, and shrews. This might be because manipulating all the complex information from echolocation requires a big, warm-blooded brain. Of course, their may be arthropods, molluscs, birds, or fish out there that use it, but we haven't yet observed.
Of course.
Natural Selection. The strongest surviving increasing the number of the strong. FASCINATING how that worked in just some 400 years!
So they observe and study other creatures for their own survival.
But how does the behavior get passed on?
ah...no that's not what I'm thinking.
I'm looking for "velocity" ...in a way.
I'm sorry it seems like this was saying that certain bacteria couldn't change to the new source. Why?
Then if you could describe whether this is an adapation or a mutation.
I see mutation yet i'm thinking this was an adaptation.
Now that's fascinating.
Thanks for the time.
You really do not get it.... So they observe and study other creatures for their own survival. But how does the behavior get passed on? ...
Only the most intelligent creatures (all in the ape family, I think) learn by watching others or educate their off springs (to pass acquired behaviors on to the next generation, such as how to process a twig by chewing on end of it etc. so that more delicious termites will stick to it when it is inserted and then width drawn from a termite nest.)