What is the advantage of growing slow?

[Omrit]

Some species will grow slowly no matter what you do, and this is strange to me. What benefit is the fish getting from growing slowly?

For example altolamprologus are famously slow growers. You can keep the tank warm, feed them 3 times a day, and change the water daily yet they will still be slow growers compared to most species. I have seen a theory about this that said "They have to grow slowly because they have special super hard scales which take more energy to grow than a regular fishes scales" this sort of makes sense but then I think about the numerous fast growing armored catfish that also have rock hard scales. There are also plenty of scaleless or less thickly scaled fish that are also slow growers.

The clown loach is a great example. They eat well, eat anything, and have no obviously complex/unusual physical traits that would warrant them growing slowly. There are even species that are nearly identical except for the color that grow much more quickly.

So if given plenty of space and plenty of food what is the advantage of growing slower than the other fish? Why would their biology want to prevent them from reaching their adult size faster when the resources to do so are available?

 

[TheTerminutter]

It probably wouldn't matter how much you feed them in captivity if they come from a wild environment with scarce levels of food.

 

[Backfromthedead]

I believe growth can be more complex than just feeding habits in communal species like the loach example. I think the dominant individuals will grow to be larger than the next competing loach in the heirarchy. If youve kept clown loach in a group its common for one or several to leap out ahead of the others pretty early on, the biggest usually being the dominant female.

I suspect this type of growth and hormones involved is propagated by breeding. So theres a lot more competition driving this growth in a wild population with a lot of breeders, and therefore larger individuals get that way quicker. CL rarely breed in aquaria...i think the only captive breeders use hormones...they still have the engrained communal behavior but i just dont think they ever face the competition and stress required for their bodies to make big growth spurts.

 

[Backfromthedead]

But to answer your question if there were a reason that an animal would choose to inhibit its growth, it would most likely be due to seasonal or otherwise periodic changes in food supply or feeding habits. A fish has to sustain its mass once it puts the mass on, and in some parts of the world fish will go with little to no food available for months.

Many fish will go without eating for extended periods when breeding and spawning as well.

 

[esoxlucius]

All fish grow at different rates, and not just from species to species, but often within the same species too. The reasons are wide, varied, and complex. But location, temp, food availability and genetics are probably the main factors.

I don't really see many advantages for the fish in the wild which are notoriously slow growers because predation must be rife. To combat this some species may have huge spawns to maximise the chances of fish reaching adulthood.

Slow growing fish in an aquarium though can be great....for us, who can enjoy the fish for longer in a tank without constantly worrying about upgrades. How crap would it be if all fish grew at the rate of an Oscar! Yikes.

 

[duanes]

Fish (and every other animal) evolutionarilly adapts traits to match its habitat and resources.
Why are rhinos in Africa giant, compared to the ones in Borneo?
Resources, predators (or lack thereof), survival of the fittest for topography (savanah/jungle).
Compare the two Chuco intermedia below....same species.....different rivers....only a few miles apart

Topography such as color of substrate, rocky or sandy, availability of vegetation.
Even within same species populations, genes will get passed on to the fittest for an area.

Tilapine species above, all evolved from the same basel ancestor.
The 1st Alcolapia get about 5 ", and live in Lake Natron, shallow, saltier than the ocean, high water temp, detritus feeders.
2nd Stomatepia pindu a predator gets 7" from a small crater lake in Cameroon Barumbi mbu, shaped like a bowl
3rd and 4th, T niloticus, riverine, generalized feeder, can get almost 2 feet long

 

[Omrit]

All fish grow at different rates, and not just from species to species, but often within the same species too. The reasons are wide, varied, and complex. But location, temp, food availability and genetics are probably the main factors.

I don't really see many advantages for the fish in the wild which are notoriously slow growers because predation must be rife. To combat this some species may have huge spawns to maximise the chances of fish reaching adulthood.

Slow growing fish in an aquarium though can be great....for us, who can enjoy the fish for longer in a tank without constantly worrying about upgrades. How crap would it be if all fish grew at the rate of an Oscar! Yikes.

Wasn't intended as a complaint I was just thinking about it not making sense. Growing as fast as possible in order to breed as soon as possible makes the most sense, but some species just won't do it which is what triggered my question.