Amazing caterpillars and metamorphosis

  • Thread starter Greg Bernhardt
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In summary, my wife and I planted some milkweed seed last fall and were happy to see a nice crop grow this spring. To our delight we found two monarch caterpillars on a leaf and decided to put them in a bug box. Caring for and watching them work was surprisingly fun and fascinating! In one week they more than tripled in size! All day they eat and poop! Usually at the same time! The two caterpillars met a few times and their antenna's were flying around. I wonder what they were saying!?Eventually, the caterpillars will cocoon and emerge as butterflies. Inside the cocoon, they turn into a liquid state before reproducing and growing into adults. Interestingly, monarchs only come
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My wife and I planted some milkweed seed last fall and were happy to see a nice crop grow this spring. To our delight we found two monarch caterpillars on a leaf and decided to put them in a bug box. Caring for and watching them work was surprisingly fun and fascinating! In one week they more than tripled in size! All day they eat and poop! Usually at the same time! The two caterpillars met a few times and their antenna's were flying around. I wonder what they were saying!?

We were excited when they attached to the top of the box ready to cocoon (technically chrysalis). I'm blown away by the metamorphosis process. Firstly, these caterpillars completely cocooned themselves in 24hrs and now bare no resemblance of a caterpillar. Secondly my wife tells me inside the cocoon they turn into a liquid* state before recreating themselves as a butterfly. I know this is grade school stuff but watching it day to day is really amazing.

Right now they are still in cocoon state. I will take a photo and then a photo when they emerge!
 
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  • #2
Greg Bernhardt said:
they turn into a liquid state

That's not exactly what happens, sounds like a HS simplification :wink:
 
  • #3
Greg Bernhardt said:
Right now they are still in cocoon state. I will take a photo and then a photo when they emerge!

Generally when they will emerge as butterflies, they will sit there for quite some days, till they grow big. If possible, fix a camera at them. Later, increase the speed of the video. It looks amazing when you see them growing up.

I observed one such cocoon on a leaf when I was very young. Now in Kolkata, who gets to see all these! :frown:
 
  • #4
Wrichik Basu said:
they will sit there for quite some days

Most species I know will sit for a few hours at most.

edit: plus, they don't 'grow', they just pump up their wings and wait for them to dry.
 
  • #5
Borek said:
Most species I know will sit for a few hours at most.
My mistake. Phone autocorrect is stupid at times.
 
  • #6
Greg Bernhardt said:
found two monarch caterpillars on a leaf
I envy you --- parasitic wasps "get" all the eggs from the milkweed I've planted. :oldcry:
 
  • #7
Bystander said:
I envy you --- parasitic wasps "get" all the eggs from the milkweed I've planted. :oldcry:
I'm located in the upper midwest, maybe we don't have them or as many? OR will they emerge as wasps!? :wideeyed:
 
  • #8
Greg Bernhardt said:
OR will they emerge as wasps!?
No. Just kill(s) the eggs. Colorado, "Front Range." The Monarchs come by, lay eggs, and move on --- two or three days later, nothing.
 
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  • #9
Little sister in New Mexico "raises" the critters --- I'll have to pass along that there have been successes in Wisconsin. Can't help but wonder if there aren't "infections" of the milkweed; the plants came from NBS Boulder, and have been "sterile" as far as Monarch production for as long as I've had them. Have to do some reading.
 
  • #10
Greg Bernhardt said:
inside the cocoon they turn into a liquid* state before recreating themselves as a butterfly.
Borek said:
That's not exactly what happens, sounds like a HS simplification :wink:
The "liquid state" occurs when many of the larval cells die (and go mushy).
The larval surface is then replaced with cells from imaginal disks that spread through the larval body a form the developing adult body inside the pupae. Other specific sets of cells create new muscle and replace many nervous system cells (but not all).

Borek said:
Most species I know will sit for a few hours at most.
edit: plus, they don't 'grow', they just pump up their wings and wait for them to dry.
After the adult form emerges, it then increases its body size beyond that of the containing pupae's cuticle. It does this by sucking in air to inflate itself before the soft cuticle hardens after its coming out of the pupae. In general, this is how insects grow in size after each molting.
With flying insects, the hardening is required for the wings to be strong enough for flight.
If they don't enlarge or if they get bent during this soft cuticle phase, they will remain that way after the cuticle hardens.
 
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  • #11
[Guess I need to be more careful about wearing glasses... I initially thought the title read arming caterpillars...] :smile:
 
  • #12
Pics please! :biggrin:
Greg Bernhardt said:
All day they eat and poop!
Haha, poop! What? No one's laughing? Nyeh. You guys don't understand me. :oldtongue: :smile:
 
  • #13
I did it! One done, one left to emerge.

butterfly.png
 

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  • #14

1. What is metamorphosis?

Metamorphosis is the process of transformation that certain animals go through in order to reach adulthood. It typically involves major changes in body structure and function.

2. How do caterpillars transform into butterflies or moths?

Caterpillars undergo complete metamorphosis, meaning they go through four distinct stages: egg, larva (caterpillar), pupa (chrysalis), and adult (butterfly or moth). The transformation occurs during the pupal stage, in which the caterpillar's body breaks down and reorganizes into the adult form.

3. What is the purpose of metamorphosis in caterpillars?

The purpose of metamorphosis is for caterpillars to undergo a complete transformation in order to adapt to their changing environment. This transformation allows them to become more specialized and better suited for their adult life as a butterfly or moth.

4. How long does metamorphosis take for caterpillars?

The length of time for metamorphosis to occur in caterpillars can vary depending on the species and environmental conditions. Generally, it takes about 2-4 weeks for a caterpillar to fully transform into a butterfly or moth.

5. Can caterpillars still eat during metamorphosis?

No, caterpillars do not eat during the pupal stage of metamorphosis. They typically consume a large amount of food during their larval stage to store energy for the transformation process. Once they enter the pupal stage, they do not have a functioning digestive system and rely on the energy stored from their larval stage.

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