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Experiment with a (real) ant.

Started by November 21, 2005 06:39 PM
78 comments, last by Jets Connor 18 years, 11 months ago
Quote: Original post by Bad Monkey
can be explained by th differences in how the organism is composed (e.g. lack of hands means climbing things or throwing-catching games are less appealing to a cat).


Yes, of course they depend on the creature structure. Pigs don't fly (I think...). Those are the limitations of what they can do. How they perform their activities, the order in which they perform them is the behavior. You can teach a cat to flush the toilet, they are physically able to do it and they will do it just like you taught them, but you don't need to teach them how to hunt a bird, and all of them will do it almost the same way.

The way a creature develops it's organism during it's lifetime respond to an order and follow certain predefined steps, It's said that this order is imposed by the enviroment and recorded into the creature's DNA. This steps respond to the internal structure of the organism, but also respond to the medium. And it's undeniable that two creatures of the same species, raised in very different places do develop the same strategies (take "strategies" as "a sucession of ordered organic states fired by a need to satisfy others" if you want it that way) for certain things, the kind of animals they preffer to hunt, or the kind of stuff they do to mate (build a good nest, or to fight each other for a mate), for example.

There is a physical predisposition to adopt (secuentially) certain strategies (or physical states) to do it. Those are the kind of "genetic remembers" I'm talking about, the innate behaviors. The more complex these suscessions of states are, the more they look like a "learned" behavior.

I agree with the notion that learned behaviors, for some specific reasons (one of which could be "repetition"), are later translated into a set of organic configurations (it the case of behaviors, this configurations are secuential and immediate organic states) and this organic configuration translated into DNA, which is transmtied to the next generation. And I personally suspect that there should be no limitation for the complexity of these states/behaviors.

Quote: Original post by Bad Monkey
Take the concept that cats and dogs don't get along... exmaples of that can be seen everywhere... so explain why my cat and my dog play together,


All I'm saying here is nothing but deductions (or speculations if you want) based on what I've experienced myself (and the different oppinions I've heared on evolution). In that specific example I could say that domestic animals are adapted to domestic uses, and domestic uses implies convivence. The notion that cat and dogs do not get along may have changed in the curse of this behavioral adaptation.

Anyway I would like to see a lamb and a lion being rised togheter and particulary watch what they do if you leave them home alone a weekend you go out somewhere.
Maybe a domestic cat and a domestic canary would be enough.
[size="2"]I like the Walrus best.
Quote: Original post by Steadtler
Quote: Original post by owl
In natural evolution, a negative mutation into vital parts of a creature are mortal for the entire species.


Why? Why a single bad mutation of one creature is bad for the whole specie?


In the case of ants (and that's the context I phrased the sentence), it would be, because just one individual is in charge of the reproduction of the whole nest. Given a finite number of queens, and an infinite probability for a mutation to be detrimental, what pops into your logic that's the logical result?

It sounds more logical/plausible to me that changes in the organic configuration of creatures is due to the adaptation I exposed in the post above.


Quote: Original post by Steadtler
It the basic of evolution, and at the risk of sounding cheezy, its The Origin of Species.


I like that. And is perfectly possible, why not? Not just because I say "no" (and I don't). :)
[size="2"]I like the Walrus best.
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The only problem with the idea that an animal's experiences can be recorded back into its genetics is that there is absolutely no evidence for it. Biologists study genetics all the time now. If there was a mechanism for recording complicated experiences into a medium that could be passed from generation to generation it probably would have been found by now. No such mechanism has been found, and the systematic observation of the behavior of animals does not suggest that such a mechanism exists.

In the case of ants, a particularly disastrous mutation in a queen could cause that queen or its offspring to become unable to survive. Then this queen will be unable to start a colony, or its colony will be inefficient and die off by a failure to do whatever ants need to do to survive. But there are many, many ant colonies in the world. And some types of ants can have more than one queen per colony. One colony might die, but the other colonies will be unaffected by the harmful mutation. And if there is a benign or beneficial mutation, the queen carrying that mutation may survive and its decendants will also carry that mutation.

The genetic code is very complicated, and the rate of mutations in nature is somewhat low. The mechanisms for copying DNA and preventing errors were also evolved. Random variations that created mechanisms that decreased genetic instability would have been beneficial to early life forms, since it would allow those life forms to reproduce in a more stable way.
Quote: Original post by owl
Given a finite number of queens, and an infinite probability for a mutation to be detrimental, what pops into your logic that's the logical result?


Im not sure I follow you there. Surely you know that there is no such thing an an infinite probability. By definition, a probability is between 0 and 1. Even if there was an infinite number of possible mutations, the probability of it being detrimental would be lower than 1. (Since good mutations exist too).

Mutation may not be the ONLY factor of evolution, but the likelihood of it being one is pretty high.
Quote: Original post by Anonymous Poster
The only problem with the idea that an animal's experiences can be recorded back into its genetics is that there is absolutely no evidence for it. Biologists study genetics all the time now. If there was a mechanism for recording complicated experiences into a medium that could be passed from generation to generation it probably would have been found by now. No such mechanism has been found, and the systematic observation of the behavior of animals does not suggest that such a mechanism exists.


Sadly, absence of proof is not proof of absence! But the likelihood is small. There are some interesting views about this in the otherwise mild "Lost World" book.

Quote:
Given a finite number of queens, and an infinite probability for a mutation to be detrimental, what pops into your logic that's the logical result?


I agree most mutations would probably kill the colony. Just like most mutations in a dog would kill the dog. But there are many more ant colonies than there are dogs, and I'm sure the life of a queen is alot shorter. So I imagine ant colonies could evolve alot faster than a large animal like a dog.
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Quote: Original post by Steadtler
Quote: Original post by owl
Given a finite number of queens, and an infinite probability for a mutation to be detrimental, what pops into your logic that's the logical result?


Im not sure I follow you there. Surely you know that there is no such thing an an infinite probability. By definition, a probability is between 0 and 1. Even if there was an infinite number of possible mutations, the probability of it being detrimental would be lower than 1. (Since good mutations exist too).

Mutation may not be the ONLY factor of evolution, but the likelihood of it being one is pretty high.


Yes, I was thinking about what I wrote and I noticed it was bad expressed. When I said infinite probability I meant that there are really big chances of bad mutations to be consecutive. Today you have lots of colonies arround the world, but it was (probably) not always that way.

The probabilities for a mutation to be exactly what a species needs to survive in a specific moment of it's evolution, and particulary for ants where the reproduction rate of the population is so low in comparision with other species (like cockroachs) is so improbable that I felt like saying it was infinite.

I preffer to belive that there exist chemical (and probably atomic) interactions between life and the medium that makes the elements that compose this creature get arranged in specific ways. And for some (still unknown) procedure, there is a way to take note of creature's current structure and write it into DNA.

The fact that there is a record of a creature's morphology (and the instructions on how to make it, and how it must develop it's structure during it's life time) speaks of an interest, need or tendency of nature on "ordering" information. There is order everywhere in the universe, everything seems to follow a pattern, so saying things happen by accident, or randomly (if there exist such a thing as "random events") looks improbable.

I've been thinking that maybe de enconding of DNA is also a sort of compression algorithm. Maybe with a certain organic configuration there is also a specific behavior that flows naturally from it.

And about mutation. If mutation happens so frequently in nature, how is that creatures don't tend to get deformed during it's lifetime that frequently? You see, reproduction of genetic information also happens in cell reproduction, so, why if you get hurt your body re-constructs the missing part flawlessly? And not only when you get hurt. All your body cells (exept for neurons) get all replaced (by reproduction) quite frequently. Why your body always follow the same pattern and doesn't mutate? There are lots of cells in most complex creatures. Mutation should pop-up into one eyes at cellular level so frequently that it should be evident. And it isn't.

If adaptations are "convenient accidents", why technical/planned breading of animals such as cows or horsed works as expected and doesn't mutate into something else "randomly" ?
[size="2"]I like the Walrus best.
Quote: Original post by owl
Yes, I was thinking about what I wrote and I noticed it was bad expressed. When I said infinite probability I meant that there are really big chances of bad mutations to be consecutive. Today you have lots of colonies arround the world, but it was (probably) not always that way.


This is a misconception I often see in regards to discussions on evolution.

Quote: Original post by owl
The probabilities for a mutation to be exactly what a species needs to survive in a specific moment of it's evolution, and particulary for ants where the reproduction rate of the population is so low in comparision with other species (like cockroachs) is so improbable that I felt like saying it was infinite.


Pretty bad assumptions here. A species is not thought to evolve quickly nor is there any reason to believe that they must evolve quickly. If a species as a whole needs to evolve in order to survive in its current environment, then its quite plainly doomed to lose its foothold in said environment. The saving graces are that most environmental changes are gradual (so that the test is not If they survive, but How Well they survive), and that most species populate multiple environments (so that Even If the species can't keep up with a changing environment, it still populates another)

Quite frankly your arguement endevours to place a species in an impossible situation when there is no obvious requirement for that condition to be enforced.

Quote: Original post by owl
You see, reproduction of genetic information also happens in cell reproduction, so, why if you get hurt your body re-constructs the missing part flawlessly? And not only when you get hurt. All your body cells (exept for neurons) get all replaced (by reproduction) quite frequently.


Yes. Individual cells split from time to time. One of the more dramatic bad mutations that can happen during this process causes cancer, where cells are encoded to split much faster than they should.

Quote: Original post by owl
Why your body always follow the same pattern and doesn't mutate? There are lots of cells in most complex creatures. Mutation should pop-up into one eyes at cellular level so frequently that it should be evident. And it isn't.


It is evident, as in the case of cancer. Its the ramifications of a mutation which is tripping you up. A single change to a single cell is isolated. Only through time is it possible for that change to propogate, and propogation is not garanteed. In the case of cells in the human body, there is a terminus where all the cells must die. Cancer isnt infectous. When you die, all your isolated cell mutations die with you.

The evolution of cells is different from the evolution of species. In the case of species mutation, the offspring is defined by *specific* strands of DNA. Lung cancer doesnt effect the DNA in sperm or egg.

You, physically, are totally defined by your DNA for sure. You contain billions of copies of your original blueprint. Pretty much all the copies have their own mutations. Most of the time, a mutation has little to no effect because that specific gene isnt used in that specific cell.

- Rockoon (Joseph Koss)
Quote: Original post by owl
The probabilities for a mutation to be exactly what a species needs to survive in a specific moment of it's evolution, and particulary for ants where the reproduction rate of the population is so low in comparision with other species (like cockroachs) is so improbable that I felt like saying it was infinite.

Evolution doesn't provide an improvement that the population needs to survive, it provides some improvement over what the population had before. Electric lights aren't necessary for survival, but after they were invented they ended up mostly replacing older forms of lighting such as buring wax or oil or gas.

If one population of ants was significantly better at surviving than some other population, it would reproduce at a faster rate and competition for survival would result in the better population becoming more prevalent. If two populations are equally good at surviving, but then there is some change in the environment such as a climate change or a new predator and one of the populations was better at surviving than the other in the changed environment, then that population would probably eventually dominate the species since it would survive better. The change in the environment doesn't cause the beneficial mutations. The mutations were already present and the change in the environment makes them useful (or maybe the species becomes extinct, and the better adapted species survive).

Quote: Original post by owl
And about mutation. If mutation happens so frequently in nature, how is that creatures don't tend to get deformed during it's lifetime that frequently? You see, reproduction of genetic information also happens in cell reproduction, so, why if you get hurt your body re-constructs the missing part flawlessly? And not only when you get hurt. All your body cells (exept for neurons) get all replaced (by reproduction) quite frequently. Why your body always follow the same pattern and doesn't mutate? There are lots of cells in most complex creatures. Mutation should pop-up into one eyes at cellular level so frequently that it should be evident. And it isn't.

Significant mutations do not happen frequently. There are biological mechanisms that attempt to prevent errors during the copying of DNA, and there is a lot of DNA that doesn't seem to serve a direct functional purpose so in many places a mutation would not even be noticable. A mutation may cause a protein to have one amino acid in some place instead of another, but amino acids can be somewhat similiar. A mutation might not necessary have a strong effect on the functioning of individual molecules.

The cells in living organisms do have occasional mutations. If the mutation prevents a cell from functioning, it might die, and then the other systems in the body would simply clean up the dead cell. Or the mutation might not significantly affect the functioning of the cell. The worst case is that the cell could start functioning in a way that is harmful to the body. Cancer is an example of this.

Quote: Original post by owl
If adaptations are "convenient accidents", why technical/planned breading of animals such as cows or horsed works as expected and doesn't mutate into something else "randomly" ?

Selective breeding does not rely on mutations during the breeding process. Natural variation already exists in the genetics of the species (caused by mutations which occured during the evolution of the species). Selective breeding selects individuals to breed based on the desired traits. The traits may be caused by the genetics of the individuals, and so some of the offspring may possess similiar traits. The offspring that possess the traits are used for futher breeding.

Quote: Original post by Anonymous Poster
Quote: Original post by owl
The probabilities for a mutation to be exactly what a species needs to survive in a specific moment of it's evolution, and particulary for ants where the reproduction rate of the population is so low in comparision with other species (like cockroachs) is so improbable that I felt like saying it was infinite.


Pretty bad assumptions here. A species is not thought to evolve quickly nor is there any reason to believe that they must evolve quickly.


Well, if you consider adaptation as part of evolution, cockroachs are able to become resistant to poison from one generation to another (and that period of time may be months). What's going on there? Mutation?


Quote: Original post by Anonymous Poster
Quote: Original post by owl
You see, reproduction of genetic information also happens in cell reproduction, so, why if you get hurt your body re-constructs the missing part flawlessly? And not only when you get hurt. All your body cells (exept for neurons) get all replaced (by reproduction) quite frequently.


Yes. Individual cells split from time to time. One of the more dramatic bad mutations that can happen during this process causes cancer, where cells are encoded to split much faster than they should.


Cancer is caused by the inability of certain cells to produce a particular component that inhibits the process of reproduction. That's a very specific kind of malfunction, can you name any other cell malfunction caused by mutation?
Cells perform lots of activities apart from reproduction. Besides, is there some proof that cancer is the result of an accidental mutation? Or is it just an assumption too? :)

Quote: Original post by Anonymous Poster
Quote: Original post by owl
Why your body always follow the same pattern and doesn't mutate? There are lots of cells in most complex creatures. Mutation should pop-up into one eyes at cellular level so frequently that it should be evident. And it isn't.


It is evident, as in the case of cancer. Its the ramifications of a mutation which is tripping you up.


Again, what evidence supports that cancer is the ramification of a mutation? I mean, to know that you need a copy of the DNA right before reproduction and the resultant mutated DNA that shows a new element which happens to be the cancer code. Is there such a proof?

[size="2"]I like the Walrus best.

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