Monarch Butterfly Larvae Are Cannabalistic
The very first meal that a Monarch Butterfly caterpillar eats is its own eggshell. In order to hatch, it eats its way out of the egg, and then polishes off the remainder of the eggshell. It then starts to wander around the leaf and if it finds another Monarch egg, it will start to eat it.
Female Monarch Butterflies lay 300-500 eggs over two to five weeks of egg-laying. Normally, a Monarch only lays one egg at a time (on the underside of a tender, young milkweed leaf). It is fairly rare to find more than one egg on a leaf, or even on the same plant. After a female lays an egg, several seconds up to a minute goes by before she lays another egg (referred to as a refractory period). During this time she usually moves on and finds another milkweed plant on which to lay the next egg. This lapse of time between the laying of each egg probably evolved to discourage the laying of multiple eggs on one leaf and to encourage the dispersal of a female’s eggs on different milkweed plants so as to decrease the chances of cannibalism occurring.
According to Dr. Lincoln Brower, renowned Monarch entomologist, a cluster of Monarch eggs on any given milkweed leaf indicates that either milkweed is in short supply, or the female that laid the eggs is either sick, very old or she has been flying for a very long time and several eggs have matured.
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Second Edition of Naturally Curious Released
Nine years after the original edition of Naturally Curious came out, a second edition is being released. New photos have been added and updates have been made. I am delighted that it is still in print, especially because numerous schools and colleges have incorporated Naturally Curious into their curricula and I would love to see this practice continue. Thank you for purchasing a copy of the first edition – your endorsement is what made a second edition possible! A short “book trailer” video of the new edition can be seen here: https://www.youtube.com/watch?v=uFtGPjPWKv0 . If you are interested in purchasing a copy of the new edition, you can order directly from the publisher by clicking on the image of the cover on the Naturally Curious blog site, or you can order it from online bookstores.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
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