Beautiful but deadly :

Monarch Butterflies

• Rania Berrada 1

Life cycle

1. The Egg

• Laid on milkweed plant• Eggs hatch into larvae in about four days

2. The caterpillar

• Eats only milkweed leaves• Milkweed is poisonous

• The caterpillar stage is 2 weeks long 2

Life cycle

3. The Pupa

• Forms a silk cocoon : The chrysalis• Forms wings and adult organs.• Pupa stage 2 weeks

Link to video of caterpillar creating chrysalis

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Life cycle

4. The Butterfly• Dries it’s wings and makes them strong. It can fly now. • Short life: about 2 to 6 weeks long. • Adults feed on nectar from flower BUT poison remains in their

body

The whole life-cycle

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The great migration• From Canada and the US to Mexico. • Hibernation. • Fly back when spring comes.

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The poison• What does milkweed contain that makes it poisonous ?

Cardenolide

• A form of a steroid (cyclic organic compounds)• Cardiac arrester • Poisonous to most vertebrates

Click on the image to get further information about the chemical structure of cardenolide. 6

Defense against predators• Caterpillar : black white and yellow bands • Butterfly : orange and black coloration

Warning of poisonous characteristics and the bitter taste !!

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Cardenolides as medecine

• Similar to digitalis (used for heart problems)

• Treat congestive heart failure• The force of muscle contractions increases

Should not exceed the stated dose !!

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Interaction with human being• Can’t kill humans. Still can run after a beautiful Monarch Butterfly …

• However, the plant is dangerous.• Extremely dangerous to the eye, can cause blindness

Don't eat them ! (Just in case…)

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Resources

Books :

• Monarch Butterfly, Volume 1 by David M. Schwartz• Monarch Butterfly Biology & Conservation (Page 55) by Karen

Suzanne Oberhauser

Internet links :

• Interactions with Milkweed• Monarch butterfly life cycle

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ContactsContact me :• Rania Berrada: engineering student in TELECOM Saint Etienne• E-mail: rania.berrada(At)telecom-st-etienne.fr• Web page: telecomAcademy

Contact a professional : • MONARCH WATCH : Dedicated to Education, Conservation and

Preservation• Website: http://www.monarchwatch.org/• E-mail: monarch(At)ukans.edu

• THE MONARCH MAGIC CO: Jenny and Jon Hobson• Website: http://www.monarchmagic.com• E-mail: monarchmagic(At)hotmail.com 11

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