Ward's World Activity Guides

Page 2 There is no better way to study life cycles than by observing the complete metamorphosis of live butterflies. Provide your students with this extraordinary experience for a spring science lesson they'll never forget. Raising Painted Lady butterflies isn't just a great hands-on demonstration of the butterfly life cycle; it's also a way to help students learn a range of fascinating concepts like migration, photonic crystals, biopolymers, and insect endocrinology. Here are nine facts your students will be amazed to discover: 1. The Painted Lady butterfly and other insects are part of a class of invertebrates within the phylum Euarthropoda, including arachnids, myriapods, and crustaceans. Arthropods have an exoskeleton, segmented bodies, and jointed appendages. 2. The Painted Lady butterflies are one of the brush-footed butterflies (family Nymphalidae), also called four-footed butterflies. They have a five to nine-centimeter wingspan and live for about two to four weeks. 3. Painted Lady butterflies are found on every continent in the world except Antarctica and Australia. 4. In the wild, the females lay about 500 eggs in their short 2 – 4-week lifespan. To put that in perspective, the best laying chicken breeds can only lay about 5 – 6 eggs per week. Ok, they're fundamentally different species, but 500 butterfly eggs are still impressive for the lovely little lady. 5. During migration, the Painted Lady species travels a phenomenal 9,000-mile round trip from tropical Africa to the Arctic Circle! 1 Sorry North American Monarchs, that's almost double the distance of your significant migration. 6. We think of a cuticle as something on our fingers and toes, but that word refers to the skin (exoskeleton) on caterpillars. The exoskeleton is made of a biomaterial called chitin (fact #9 below explains the cool way chitin also affects butterfly wings). Chitin is one of the most important biopolymers in nature.2 It's the same biomaterial that lobsters, crabs, and other arthropods use in their hard exoskeletons. Strong hydrogen bonds between the chitin chains give chitin exceptional toughness, protecting the caterpillar's soft insides until it goes through metamorphosis. Or in the case of the lobster, protecting its succulent flesh until it turns into our buttery, gourmet dinner! Being that tough means that chitin doesn't stretch with growth, so caterpillars and other arthropods periodically shed their exoskeletons, i.e., they molt. 7. The larval stage of the Painted Lady butterfly is about 5 to 10 days. The caterpillars will eat and eat and eat; after all, how else are they going to turn into gorgeous butterflies? Caterpillars can consume 200X their birth weight in less than two weeks. They will increase their body mass by as much as 1,000 times or more during this stage. Imagine a seven-pound newborn child consuming 1400 pounds of formula in two weeks.3 As the caterpillar grows, its skin gets too tight, triggering a hormone (ecdysone) that regulates the molting process. A caterpillar changes its skin about four times before it's fully grown and ready to go into the chrysalis stage. And, no surprise, the vora- cious caterpillar doesn't just shed that skin; it digests and reabsorbs most of it. What an appetite! 9 facts you may not know about Painted Lady Butterflies and how to use them in the classroom

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