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.
Our iOS Apps
Our iOS Apps
The Bat App
The Bat App is a field guide to bats that is full of cool facts (not myths) about all 47 bat species in North America and the three vampire bats found in Mexico and Central and South America. There are hundreds of images (many are courtesy of famed bat ecologist, Dr. Merlin Tuttle), and in-depth information about each species as well as locating bats by state or province. Included in the app is a comprehensive FAQ with over 80 questions, as well as tips on how to spot bats. The three vampire bat species are covered in great detail, so you can stop worrying about these little bats and get some sleep already!