top of page

Monarch caterpillars molt (shed their skin) five times throughout their larval stage. The "skin" that is left behind is actually the caterpillar's exoskeleton. An insect's skeleton is on the outside, as opposed to on the instead like mammals, fish, reptiles, amphibians and birds. Endoskeletons provide support inside the body in the form of bones and cartilage, whereas As caterpillars grow, their exoskeleton gets too tight, so they need to shed it in order to continue to grow. Each molt results in a new "instar" stage. Therefore, when the egg hatches, that tiny 2 mm caterpillar is in its first instar stage.

 

It will molt three more times and grow exponentially over a couple of weeks. Each stage lasts 3-5 days. The fifth and final molt is when the fifth instar caterpillar becomes a chrysalis.

Comparison3MilkweedFlowers.jpg

Welcome!

...about cool nature topics

...in community science programs

...what we still have before it's too late

...Latest Environmental News & Blogs

icon180 copy.png
icon180 2.png
rpicon180.png
icon180.png
hsicon180.png
kwicon180.png

Affiliations

Proud Partner Logo_transparent backgroun
SAH_Brand_Mark_Sig_H1L copy.png
Naturedigger_registered_tm copy 2.png
bottom of page