Raising Butterflies:
A Hydrogen Isotope Experiment from Environment Canada and the University of Kansas


NOTE: This experiment was done by Mr. Smith's 1996-97 third grade in Granger, Texas. This year's 4th grade class in Hannibal will be having their own adventures with Monarchs. We are expecting 10-12 larvae from the people at Monarch Watch at the University of Kansas during the first weeks of school.

What We Were Doing -- On 8-16-96 we started raising little Monarch butterfly caterpillars from eggs. The eggs were stuck on milkweed leaves and most hatched into caterpillars (also known as larvae). Monarch caterpillars only eat milkweed. We fed our caterpillars milkweed that grew in a horse pasture and had been watered only by rain. The caterpillar on the brush is 3.2 centimeters long. It is in the 5th instar stage and about to become a pupa!


What Our Scientist Partners Were Doing --Scientists at Environment Canada were studying the Monarch to learn more about its migration path. Scientists at the University of Kansas assisted with wild rearing and captive control experiments. So what are hydrogen isotopes and how do they help scientists find out about Monarchs? Isotopes are forms of elements. Deuterium is one isotope (or form) of hydrogen. And we all know that hydrogen and oxygen make water, right? Right.And deuterium is in rain water and rain in different places has different amounts of deuterium. Minnesota rain has different amounts of deuterium in it than Georgia or Texas. Rain with deuterium in it falls on milkweed, Monarch butterflies lay eggs on milkweed, the eggs hatch into hungry caterpillars which eat the milkweed leaves, and later turn into butterflies and fly away. So how do scientists put all this together and know where the butterflies came from?

Here is a scientific drawing by Chad.

Here is another scientific drawing by Ashley.

Can you tell the difference between the male and female Monarch? See the dot? How are the veins different?

Inside our 36" x 36" x 36" butterfly cage: This chrysalis is one of fifteen we raised and studied. Up close, you'll find tiny gold mystery dots. Why? What do they do?

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