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joey'd is da man
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Discussion Starter · #1 ·
I was searching the web for info on Eartheaters and I came across an intreging site about Eartheaters.







heres a handy link
 

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joey'd is da man
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Discussion Starter · #3 ·
does it match up with what you know about these fishes?
 

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Photographic Genius
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It doesn't really help that much. It just states in more of a scientific jargon that the two species are easily confused. I will take some pictures from that book I recommended when I get home from work. Perhaps that will help. They are actually very easy to tell apart. According to that, all the highly pearled ones are S. leucosticta. They even have a slightly different body shape. S. juraparis tend to appear more streamlined, especially at the snout.

I would venture to say that all of the fish pictured above, except for the bottom one, are S. leucosticta. But remember, I am no ichthyologist...I'm just going by what I have seen for myself along with research.
 

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joey'd is da man
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Discussion Starter · #5 ·
so how is it that one species of fish can look so differant than others of the same species?
 

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Here comes the scientific part! First of all the concept of a species is one still being argued by graduate students and professors all over. Second, geographic variation is always (and often) a possibility. Third, I'd say the conditions they were raised in; social, food, water conditions, etc. Fourth I'd go with dominance (more social conditioning) where testosterone (or 11-keto-testosterone...another story) influences appearance.

...And fifth, you can be a loser and inject fish with artificial dye
 

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joey'd is da man
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Discussion Starter · #7 ·
acestro said:
Here comes the scientific part! First of all the concept of a species is one still being argued by graduate students and professors all over. Second, geographic variation is always (and often) a possibility. Third, I'd say the conditions they were raised in; social, food, water conditions, etc. Fourth I'd go with dominance (more social conditioning) where testosterone (or 11-keto-testosterone...another story) influences appearance.

...And fifth, you can be a loser and inject fish with artificial dye
can you explain these further?
 

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That's what this forum is for!
I think I'll leave species concepts for another thread. It boils down to does being able to reproduce and produce viable offspring make you a species or is it something more geographical or genetic. I guess that's not really boiled down...I'll get back to that!


Geographic variation is more like "races" or "subspecies". No one argues that we are one species but we have different races. If you catch a banded water snake in Louisiana it will have less bands than a banded water snake in Florida. Still considered the same species.

Conditions breaks down to "you are what you eat" and what other chemicals make up or influence what makes up yourself. Fast flow can lead to different muscles or fin development or loss that are plastic, meaning they won't look the same in different situations. Interactions can be included here with fish of the same and different species.

Social effects and the hormones work because being dominant or suppressed affects the hormone mixture and hormones have a lot to do with fish color. I'd also like to add that something as simple as the background the fish is against works too because a lot of the color in a fish comes from reflective materials and dark or light colors can influence mood as well.

And injecting dye is just us human losers thinking we can match up with what God and/or nature does so much better!
 

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joey'd is da man
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Discussion Starter · #9 ·
so is a species a species because it will breed with each other?

as far as I know plattys can interbreed with swordtails - but these are seperate species


how does that work?
 

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It doesn't. It's the biological species concept and it has inherent flaws unless you add stipulations to it. A supporter of this concept would, however, point out that there are barriers to this happening in the wild. Consistant differences in the genetics could work better but this can possibly make for too many species! Not trivial, either. Think endangered species act. What do we protect?
 

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joey'd is da man
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Discussion Starter · #11 ·
OK so in plain English there is no true definition os what makes a species a species and not a "varient"


so how do we know if something is one thing or another?

like a swordtail - how is it not the same as a platty, but a "variation"???
 

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How we know is consistent differences between the two kinds of animals. We also know by whether they are officially named by us (humans) as a species. It may have no evolutionary consistency with other decisions or may have no evolutionary basis at all.
 

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joey'd is da man
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Discussion Starter · #13 ·
can you please explain further?
 

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Some would say it's as simple as whether or not they can breed.
Can't breed=different species. (it can get more complex but...)

Some say it's one or more "fixed" gene differences between two populations. For example; swordtails all have swords (amongst other things) and platys don't. Being able to breed means not so much.

The latter works better because it most likely represents what has happened evolutionarily.
 

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joey'd is da man
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Discussion Starter · #15 ·
so there really is no true defenition then?
 

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joey'd is da man
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Discussion Starter · #17 ·
so how can you know if you have a seperate species or a variation?
 
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