Whats the big deal about soft water cichlids in hard water. Rant
- Thread starter duanes
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Hello; The thread has morphed into a discussion of adaptability. This is a fine direction so I am not being critical. We do need to keep in mind that adaptation is a different thing for an individual than for a species.
In a natural setting the environment can and does over long time periods change. Hard water can become soft. Wet area can become dry and so on. A species can adapt if the changes are slow enough. That may mean out of many thousands of offspring most are adapted for the old conditions and only a few have better tolerance for the new changing conditions. In time those better suited to the new conditions will have the greater numbers of offspring. Those offspring should have a slightly higher percentage of fry with the new adaptations. This goes on until most individuals are well adapted to the new conditions (SIDE NOTE - This overlooks the notion of a suddenly appearing selective mutation which is a whole nother thing and might just be the driver of most evolution.) Thing is a species wide adaptation throws away a ton of individual lives.
Individual adaptation is different in my view. An individual fish placed in out of range conditions seems much more likely to be stressed in a number of ways. An individual does not have the overall plasticity of an entire species. I use to fish a lot. The same body of water had many different conditions during the seasons so any successful individuals have to be able to handle the different conditions at different times of the year. This does not mean I can take an individual fish from local waters and put it into a very different environment and expect it to thrive. I may be able to take thousands of individuals of a species to a different environment and see which individuals actually survive. Might have to move many sets of thousands before I get a few that tolerate the new conditions well enough to thrive. Many may live for a while but never reproduce. May be that mature individuals live longer than juveniles or the other way around. May be they spawn and the fry never survive My point being we fish keepers are dealing with individuals.
I suppose I could start a breeding program and over time with lots of culling and selective breeding come up with a soft water fish that does well in hard water. I also bet the resulting fish would have morphological (physical) changes.
I think of the Russian experiment to breed a fox with very distinctive fur so it was less aggressive. They wound up with a less aggressive fox alright but the fur distinction was also lost.
I live in karst (limestone) formation country. I keep fish more suited to my water and look at the pictures of those I cannot keep well.
In a natural setting the environment can and does over long time periods change. Hard water can become soft. Wet area can become dry and so on. A species can adapt if the changes are slow enough. That may mean out of many thousands of offspring most are adapted for the old conditions and only a few have better tolerance for the new changing conditions. In time those better suited to the new conditions will have the greater numbers of offspring. Those offspring should have a slightly higher percentage of fry with the new adaptations. This goes on until most individuals are well adapted to the new conditions (SIDE NOTE - This overlooks the notion of a suddenly appearing selective mutation which is a whole nother thing and might just be the driver of most evolution.) Thing is a species wide adaptation throws away a ton of individual lives.
Individual adaptation is different in my view. An individual fish placed in out of range conditions seems much more likely to be stressed in a number of ways. An individual does not have the overall plasticity of an entire species. I use to fish a lot. The same body of water had many different conditions during the seasons so any successful individuals have to be able to handle the different conditions at different times of the year. This does not mean I can take an individual fish from local waters and put it into a very different environment and expect it to thrive. I may be able to take thousands of individuals of a species to a different environment and see which individuals actually survive. Might have to move many sets of thousands before I get a few that tolerate the new conditions well enough to thrive. Many may live for a while but never reproduce. May be that mature individuals live longer than juveniles or the other way around. May be they spawn and the fry never survive My point being we fish keepers are dealing with individuals.
I suppose I could start a breeding program and over time with lots of culling and selective breeding come up with a soft water fish that does well in hard water. I also bet the resulting fish would have morphological (physical) changes.
I think of the Russian experiment to breed a fox with very distinctive fur so it was less aggressive. They wound up with a less aggressive fox alright but the fur distinction was also lost.
I live in karst (limestone) formation country. I keep fish more suited to my water and look at the pictures of those I cannot keep well.
This brings up an interesting aspect of adaptation. How long does it actually take to produce an adaptable population, and how many individuals survive or die in producing that adaptation?
As with what happens with some soft water species that spawn in high pH water.
I had a spawning group of Alcolapia a few years back, they were producing in waters around the lowest temp range of their norm, (low 80s), in Milwaukee tap water, with conductivity very low in comparison to Natrons higher than sea water osmotic content. Almost all my fry ended up females, but their survival rate was quite good.
Since Lake Natron is only 8000 to 14,000 years old (a tiny blip in evolutionary time) it is obvious these species with Tilapine ancestores adapted and developed quite quickly (less than 10,000 years).
Does this kind of accelerated evolution apply to taking already acclimated fish the have developed over millions of years, and putting them into differing conditions in an aquarium translate.
To go from their generalist Tilapine ancestor, that probably had spawns in the thousands, to Alcolapia with spawns of less than 100, how many in those thousands perished?
How many died of disease from elevated temps, and near 10 pH.
Very drastic changes, but to get there they had to evolve into what is considered a separate species
Even though cichlids are known to be plastic, would taking a Uaru fern .... from pH 5 and dropping it in Milwaukee pH 8 high mineral content water, equate to the 8000 years of survival of the fittest selection, that generations took to produce Alcolapia from a generic Tilapia.
Are aquarists willing to watch 19 of their 20 Uaru die from lack of adaptation, as it might occur in nature?
Or as in many soft water species do forced into a hard water aquarium, , not die of acute illness, but end up scarred from the chronic effects when not provided with proper water parameters, and/or with water changes that do not mimic the constant changes and lack of nitrate provided by nature.
As with what happens with some soft water species that spawn in high pH water.
I had a spawning group of Alcolapia a few years back, they were producing in waters around the lowest temp range of their norm, (low 80s), in Milwaukee tap water, with conductivity very low in comparison to Natrons higher than sea water osmotic content. Almost all my fry ended up females, but their survival rate was quite good.
Since Lake Natron is only 8000 to 14,000 years old (a tiny blip in evolutionary time) it is obvious these species with Tilapine ancestores adapted and developed quite quickly (less than 10,000 years).
Does this kind of accelerated evolution apply to taking already acclimated fish the have developed over millions of years, and putting them into differing conditions in an aquarium translate.
To go from their generalist Tilapine ancestor, that probably had spawns in the thousands, to Alcolapia with spawns of less than 100, how many in those thousands perished?
How many died of disease from elevated temps, and near 10 pH.
Very drastic changes, but to get there they had to evolve into what is considered a separate species
Even though cichlids are known to be plastic, would taking a Uaru fern .... from pH 5 and dropping it in Milwaukee pH 8 high mineral content water, equate to the 8000 years of survival of the fittest selection, that generations took to produce Alcolapia from a generic Tilapia.
Are aquarists willing to watch 19 of their 20 Uaru die from lack of adaptation, as it might occur in nature?
Or as in many soft water species do forced into a hard water aquarium, , not die of acute illness, but end up scarred from the chronic effects when not provided with proper water parameters, and/or with water changes that do not mimic the constant changes and lack of nitrate provided by nature.
Hello; Interesting that we both had similar thoughts. I must have been writing my post about the same time as you.
There is a notion went around years ago that appears to be proving out. Two examples come to mind. The pythons in Florida and the "killer "bees. Many thought both these species would be limited to more tropical climates but it appears to they are moving north and surviving the occasional cold spell.
The notion if I recall correctly is families of plants and animals have over long time been exposed to and adapted to succeeding and very different environments. That many species have a data bank so to speak of those adaptations stuck back and kept in their DNA. That a desert adapted species has some information about cold survival tucked away. So a desert species can if given enough time adapt to other environmental conditions without having to reinvent the "evolutional wheel" so to speak. Sort of a genetic memory perhaps. (NOTE- this does not include the "behavorial adaptations" that individuals can use. The pythons and the bees may use behavior to survive cold short term just as I put on a coat.
No argument. And I'm not saying population dynamics is no longer a factor, but the science is advancing in genetics and this is no longer the complete picture, which includes genetic switches, epigenetics, and complexities we're still unraveling. Genetic switches mean that it's not just a species that can adapt over long (or short) periods, which clearly happens. But adaptation may be within a single generation or in an individual during its lifetime, in some cases within weeks, days, hours or less. It simply depends on the species and condtions we're referring to. This means some species (or even individuals) are capable of repeatedly switching according to oscillating conditions.. take nuchal humps, for example, or intestinal morphology. This is software, or at least software-like.
Among scientists, some compare DNA to software, some don't care for the comparison. The software comparison works for me because I used to be a software technical writer, so it's an easy and obvious comparison. What's undeniable is the system is much more sophisticated and complex than we once thought and when you apply some of this to biological adaptation, species radiation, etc. it has to be integrated and accounted for in our models for how it all works. Maybe fifteen years ago I had a conversation with a scientist acquaintance about species radiation and invoked the traditional model-- population dynamics, etc. He essentially rolled his eyes at me and politely changed the subject, he knew it's not that simple. Since then, and partly triggered by that, I've done a lot of reading on genetics (I Iused to be more into theoretical physics). Huge subject, hard to absorb and keep up with it all-- I say hard, more like impossible unless it's your field-- but it changed my understanding of how it all works.
Hopefully this isn't too for OT, but here's a sample of what I'm talking about.
https://www.quantamagazine.org/how-the-dna-computer-program-makes-you-and-me-20180405/
We're far from understanding it all. We should expect future research to further change our model of how it all works.
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I say switching genes off and on above... even that can be simplistic, in some cases DNA segments are actually substituted or rewritten according to existing instructions from controlling mechanisms...
Theoretical physics hasn't advanced substantially in the past 20 years, they found the Higgs boson, yay. String theory is decades old and still unproven. Genetics, though, wow!
None of what I've written is meant to disprove that we should keep fish within their natural limits or conditions. I agree on that. But we should also understand their ability to adapt-- within reason and limits-- to circumstances in our tanks that don't match exactly their wild homes.
Theoretical physics hasn't advanced substantially in the past 20 years, they found the Higgs boson, yay. String theory is decades old and still unproven. Genetics, though, wow!
None of what I've written is meant to disprove that we should keep fish within their natural limits or conditions. I agree on that. But we should also understand their ability to adapt-- within reason and limits-- to circumstances in our tanks that don't match exactly their wild homes.
I've been holding back here for years on this subject, finally had to let it all out.
