Monarch Butterflies are Poisonous

Friday, July 2, 2010

I never realized how much there is to learn about monarch butterflies until my daughter found a hurt butterfly and brought it into the house. I have since learned how to fix a broken wing, and learned that adult butterflies do not eat, they drink. The caterpillar of almost all butterflies eat various parts of plants. Each species may eat only a few kinds of plants or plant parts.

The monarch butterfly is sometimes called the "milkweed butterfly" because its larvae eat the plant. Adult female monarchs lay their eggs on the underside of milkweed leaves. These eggs hatch, depending on temperature, in three to twelve days. The larvae feed on the plant leaves for about two weeks and develop into caterpillars about 2 inches long. After awhile, the caterpillars attach themselves, head down, to a convenient twig. They shed their outer skin and begin the transformation into a pupa (or chrysalis), a process which is completed in a matter of hours. The caterpillar completes the miraculous transformation into a beautiful adult butterfly in about two weeks.

Most predators have learned that the monarch butterfly makes a poisonous snack. The toxins from the monarch's milkweed diet have given the butterfly this defense. In either the caterpillar or butterfly stage the monarch needs no camouflage because it takes in toxins from the milkweed and is poisonous to predators. Many animals advertise their poisonous nature with bright colors... just like the monarch!

Can you see the difference?

The butterfly to the left is the Viceroy Butterfly
(Limenitis archippus)

He's evolved to look like the poisonous monarch to the right so that predators will avoid him too!

Heartland Perspective - by Templates para novo blogger