Tokis-Phoenix
^_^
In my opinion, i think the larger, older, slower reproducing and more intelligent a fish is the more likely it is to have pain receptors- i shall give some examples of these factors;
a. YOUNG FISH=FRY; Guppy fry for example i doubt have any pain receptors in them in the early stages of their lives- when you consider the huge losses a 30 strong batch of fry experiences in the wild and the means of their deaths it seems pretty pointless to put a lot of energy into building a highly tuned pain receptor system because most things that kill them, they have no chance against for surviving anyways.
The whole point of evolving a pain receptor system is to avoid making the same mistake again, you can also only evolve it if you survive from that mistake and live on to produce offspring that may inherit the same ability that saved you, but when a fry is about to get eaten by a larger predatory fish it has little chance of ever surviving.
I believe pain receptors are somthing that grow and multiply in fish as they grow get older and this system is very undeveloped in small fry- there is little point of the fry experiencing great pain if it has no chance of survival against, say a big predatory fish eating it. When you also consider the huge amounts of fry guppys produce they have only evolved this because of the huge number of ways they can die and so need to reproduce on a fast scale to survive, but this life insurance and the insurance of instaincts like moving away from somthing that could posibly pose a threat is more than enough to ensure that some fry will always survive- animals/fish though never evolve abilitys that they don't need to survive mainly because these abilitys need energy=food to run and it is pointless wasting energy on somthing that will serve you little, like pain receptors in the early stages of life of a fry.
I think this goes for practically all types of small fry.
b. LARGE AND OLD FISH; i believe the larger the fish, the more likely it is to have pain receptors in it as size takes a while to put on and the larger you get the less ways their are for you to die in comparison to a small defenceless fry. It would make sense for a guppy for example, to start investing more and more energy into a pain receptor system as they grow simply because it becomes more useful and the chances of it working efffectivily greater and thus a much more cost effective system to invest in.
c. INTELLIGENCE; it is a known observation that the more intelligent an animal/fish, the more likely it is to have pain receptors, this partly because more intelligent animals take longer to develope and mature than less intelligent animals and also because intelligence is often found in animals that rely less on instincts and senses of the body like smell and hearing to guide them through life than animals that do.
When you are evolving you have a selection of things that can be used as life insurance but brain capacity and body size limits how many you can invest in, intelligence can be a bit overated in terms of which life insurance is the best as the majority of animals that live in the world simply do not need it to survive. Without many instincts to guide you through life at hand though it is pretty vital.
Example= what need does a fly need as intelligence when it can already produce on a rapid scale and has high tuned instincts that already succesfully ensure its survival? It would be a waste of energy to produce such a system when it is already thriving on its current ones...
A gorrila though, which does not have great or highly tuned hearing, smell, fast reproductive rate or unlimited food source, needs intelligence on a great scale to survive as its body is less invested in other forms of life insurance.
In less defined exmples though such as fish, these examples still do aply and i am sure it is the same for a fish too.
REPRODUCTIVE RATES; the final factor, i do think the speed of which a fish can reproduce and grow is also an important factor of how nesarsary a highly tuned pain receptor system is as the longer it takes for you to reach maturity and produce a small number of offspring, the more important having a pain receptor system is.
As i mentioned earlier it would be of little use for a young guppy fry to have such a system as the energy it costs to run it would rarely ever pay off and save you. Having large amounts of fry on a regular basis helps overcome the large losses of fry that are lost without this system.
But for an animal like a foal or calf, where producing and successfully raising offspring is slower and on a smaller scale and the parents have to invest more energy into the survival of the baby, any system like pain receptors becomes much more inportant in rasing offspring succesfully, im sure it is the same for fish in a sense after the other factors like size, stage of growth and intelligence have been taken into consideration.
...
I think i have missed some points but i hope you get the jist of them anyways- at this point in time i think a guppy fry or neon tetra is far less likely to feel pain at all or on a big scale as say, a full grown oscar or sailfin plec.
I think for example, using freezing as a form of euthanasia is acceptable on a tiny fry but totally unaceptable on say, a 10inch plec. This is based on my conlusions of the baove points. What do you think?
a. YOUNG FISH=FRY; Guppy fry for example i doubt have any pain receptors in them in the early stages of their lives- when you consider the huge losses a 30 strong batch of fry experiences in the wild and the means of their deaths it seems pretty pointless to put a lot of energy into building a highly tuned pain receptor system because most things that kill them, they have no chance against for surviving anyways.
The whole point of evolving a pain receptor system is to avoid making the same mistake again, you can also only evolve it if you survive from that mistake and live on to produce offspring that may inherit the same ability that saved you, but when a fry is about to get eaten by a larger predatory fish it has little chance of ever surviving.
I believe pain receptors are somthing that grow and multiply in fish as they grow get older and this system is very undeveloped in small fry- there is little point of the fry experiencing great pain if it has no chance of survival against, say a big predatory fish eating it. When you also consider the huge amounts of fry guppys produce they have only evolved this because of the huge number of ways they can die and so need to reproduce on a fast scale to survive, but this life insurance and the insurance of instaincts like moving away from somthing that could posibly pose a threat is more than enough to ensure that some fry will always survive- animals/fish though never evolve abilitys that they don't need to survive mainly because these abilitys need energy=food to run and it is pointless wasting energy on somthing that will serve you little, like pain receptors in the early stages of life of a fry.
I think this goes for practically all types of small fry.
b. LARGE AND OLD FISH; i believe the larger the fish, the more likely it is to have pain receptors in it as size takes a while to put on and the larger you get the less ways their are for you to die in comparison to a small defenceless fry. It would make sense for a guppy for example, to start investing more and more energy into a pain receptor system as they grow simply because it becomes more useful and the chances of it working efffectivily greater and thus a much more cost effective system to invest in.
c. INTELLIGENCE; it is a known observation that the more intelligent an animal/fish, the more likely it is to have pain receptors, this partly because more intelligent animals take longer to develope and mature than less intelligent animals and also because intelligence is often found in animals that rely less on instincts and senses of the body like smell and hearing to guide them through life than animals that do.
When you are evolving you have a selection of things that can be used as life insurance but brain capacity and body size limits how many you can invest in, intelligence can be a bit overated in terms of which life insurance is the best as the majority of animals that live in the world simply do not need it to survive. Without many instincts to guide you through life at hand though it is pretty vital.
Example= what need does a fly need as intelligence when it can already produce on a rapid scale and has high tuned instincts that already succesfully ensure its survival? It would be a waste of energy to produce such a system when it is already thriving on its current ones...
A gorrila though, which does not have great or highly tuned hearing, smell, fast reproductive rate or unlimited food source, needs intelligence on a great scale to survive as its body is less invested in other forms of life insurance.
In less defined exmples though such as fish, these examples still do aply and i am sure it is the same for a fish too.
REPRODUCTIVE RATES; the final factor, i do think the speed of which a fish can reproduce and grow is also an important factor of how nesarsary a highly tuned pain receptor system is as the longer it takes for you to reach maturity and produce a small number of offspring, the more important having a pain receptor system is.
As i mentioned earlier it would be of little use for a young guppy fry to have such a system as the energy it costs to run it would rarely ever pay off and save you. Having large amounts of fry on a regular basis helps overcome the large losses of fry that are lost without this system.
But for an animal like a foal or calf, where producing and successfully raising offspring is slower and on a smaller scale and the parents have to invest more energy into the survival of the baby, any system like pain receptors becomes much more inportant in rasing offspring succesfully, im sure it is the same for fish in a sense after the other factors like size, stage of growth and intelligence have been taken into consideration.
...
I think i have missed some points but i hope you get the jist of them anyways- at this point in time i think a guppy fry or neon tetra is far less likely to feel pain at all or on a big scale as say, a full grown oscar or sailfin plec.
I think for example, using freezing as a form of euthanasia is acceptable on a tiny fry but totally unaceptable on say, a 10inch plec. This is based on my conlusions of the baove points. What do you think?