Butterfly

[har0bed1813]

How could a butterfly be the result of random mutation... The developemental stages are so specific it is hard to imagine an inbetween form. Could someone shed some light?

[Dr.Stein]

What do you mean by "random mutation"?

[har0bed1813]

you know... genetic faults due to mutation, and then with survival of the fittest you get the genes that work.. but how can such a complex thing as a 3 stage butterfly developement thingy work????

[mith]

If you're talking complexity, there are many creatures that have a larvae form, sponges, sea squirts, frogs....

[har0bed1813]

yes, I know that, but what I don't understand is how it can be helpful in surviving to have a multiple stage developement.

[James]

Think of metamorphosis as growing up from young to adult, just in one spurt.

[Dr.Stein]

Because they are equipped with several genes that are responsible to each differentiation stage (metamorphosis phases), that's help them to keep survive in each of their instars (development phases).

Also, there are a couple of hormones that regulate their stages of life, you know JH and ecdyson. Oh this reminds me of a research done by my friend from another lab:
- She kept Attacus atlas (wild silkmoth cater... oops larvae... it is the same though hehe... OMG, I am shivering and can feel my cold sweat while writing this...awawawawaa...) in her lab. I called this moth as 'kite' because if you spread wings of this moth, it will as long as your 15 inch monitor whoaaaaa...
- She administered JH for the first group and applied ecdyson for the second group. The third group was for control.
- After few times, larvae from the first group became giant larvae compared to the third group (whoaaa I saw monster brrrrr...), the instar phase was longer. While larvae from the second group started to make a cocoon, actually that was too early or their instar phase was shorter, because the third group (control) still in their middle instar phase.

[mith]

How it would be desirable to have multiple stages?

Think food sources. If adults and adolescents ate the same food, there would be a potential food shortage, so this is a form of resource partitioning.

Caterpillar-leaves
Butterfly-nectar

[Dr.Stein]

Because JH keeps insects in larva stage (juvenile), so they will have extra instar phase(s).

[har0bed1813]

thank you.. i think i get it

[Darwin Dude]

[i]How it would be desirable to have multiple stages?

Think food sources. If adults and adolescents ate the same food, there would be a potential food shortage, so this is a form of resource partitioning.[/i]

Actually I don't think that is a good argument as it would imply some sort of group selection. I suspect that it is more likely that some advantage accrues to the individual caterpillar from having the food source they do as teenagers..rather than any implied competition with the adults.

[Speadskater]

and if they stayed in their larva stage they would only eat leaves their whole life, which might cause a shortage of food and may kill the tree that provides the leaves. but having two stages allow them to use both nectar and leaves so that no resource is used too much or too little.

If you can use the nectar to your advantage why would you waste it and just eat just leaves?

Again...I'm young so if I'm wrong tell me. this is just my thinking with little experiance.