BUGS BUGS BUGS! Museum Victoria Early Learning Program. Bugs Bugs Bugs! Resource Kit. Acknowledgements

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1 BUGS BUGS BUGS! Museum Victoria Early Learning Program This kit was designed to provide background information that will enhance children s visit to the Bugs Alive! exhibition or to see the bugs in the Children s Gallery. It is intended to provide information about bugs and ideas for activities that will build on the experiences children had during their visit. These are designed in sections to cater for a variety of learning experiences. 1. Background information about bugs 2. Science experiences relating to bugs 3. Social and musical experiences 4. Dramatic and creative experiences 5. Group experiences and resources 6. Images that may be reproduced Acknowledgements Museum Victoria would like to acknowledge and thank Sue Elliot and Anne Smith for developing these resources. Illustrations by Sharyn Madder and Graham A. Milledge. Photographs by Alan Henderson. All photographs and illustrations copyright Museum Victoria (2000, 2003). Other materials republished with permission. These materials may be reproduced for teaching purposes and personal use. Pernission to reproduce any material for other purposes must be obtained from Museum Victoria. 1

2 Background information Case Moths Children and adults are fascinated by case moths and often bring them in to early childhood centres. The caterpillar of this moth makes a silk bag or cocoon for protection and attaches small pieces of stick to it, which it has chewed off to the correct length. It does this while it is in the caterpillar eating stage not just when it is ready to pupate. Children can often see the front of the caterpillar crawling along moving its bag as it goes. Some case moth caterpillars make a type of silk ladder to help them climb up walls or trees. The case becomes a stationary cocoon while the caterpillar is pupating. The female case moth is usually wingless and never leaves her case. Beetles Beetles are insects that come in a variety of shapes and sizes. Children may remember the giant cut away/light up Rhinoceros Beetle model at Bugs Alive exhibit and the actual beetle beside it and/or the Dung Beetle or the Water Beetle exhibit. The beetle featured in the Children s museum is the Rhinoceros Beetle. The Rhinoceros beetle with its hard shell and prominent horn is very strong. It buries animal dung under the ground as a food source for itself and its larvae. In this way it is very beneficial for soil fertility. Beetles go through complete metamorphosis. The larva can be a grub, worm or squat type shapes that children may find digging in the ground. Beetles then have a pupa or resting stage. The adult has biting mouthparts. Some eat plant material while some are carnivorous. Ladybirds are beetles. Weevils with their distinctive long snout are beetles. Click beetles that can bend their body and then spring in the air are fascinating beetles for children. The Rhinoceros beetle is featured in the Children s Museum. Children may also remember the giant light up/cut away model in the Bugs Alive exhibit. It has a distinctive horn on its head and hard blackish covering. It digs burrows in the ground and moves animal dung into these for itself and its larvae to eat. It is very strong moving many times its own weight. Silk Worms All beetles have a hard protective body and first pair of wings. These hard wings are not used for flying. Gauzy ones that have been folded underneath are. The hard wings are held out to the side. This can make the beetle appear clumsy when it flies. Silk worms are the larval (caterpillar) stage of the silk worm moth (Bombyx mori). It is bred commercially in some countries for the silk thread that the caterpillar uses to spin its cocoon. Eggs can be purchased from Monique Fenner in Melbourne. (See resources section.) Caterpillars only eat Mulberry leaves and need fresh ones each day. Old leaves and droppings must be removed daily. Caterpillars are large making it easy for children to observe the process of spinning the cocoon. Adult moths don t feed and live only a few days long enough to mate and lay eggs. 2

3 Snails The common garden snail has a very poor reputation with gardeners, but is a fascinating creature and easy to manage with children. The snail has a large soft muscular foot that it moves on and its movement is best observed from the underside through glass or perspex. The whole foot can be withdrawn into the shell, particularly in dry weather this helps conserve moisture. Children can observe the two pairs of antennae, the larger ones with black eyespots are for seeing and the smaller ones are for sensing touch and smell. Snails breathe through a hole just under the rim of the shell, watch carefully for the hole to open and close. The same hole is also for excrement! Snails eat plants using a rasp like structure called a radula. If keeping them temporarily, try a range of plant materials to observe their preferences. Snails have both male and female parts, but do mate to exchange sperm. Snail eggs are laid in moist soil and appear like tiny whitish balls of jelly. About forty eggs are laid and they take about three weeks to hatch into baby snails. The common garden snail is closely related to water snails and sea snails (seashells). Earthworms Earthworms are often found in the soil when gardening with children, but can be kept in worm farms to compost food waste too. The most obvious features of earthworms are the segmentations or rings and the clitellum or saddle which has a reproductive function. Each body segment has four pairs of bristles (only observable with a strong magnifier) which secure the worm, while the body muscles contract to move the worm along. Worms are light sensitive and therefore will burrow down when exposed. Also, their bodies need to be moist to allow them to breathe through their skin. However, too much water brings them to the surface to avoid drowning in their tunnels in the ground. Sometimes children may find worm castings (or poo) like little coils of soil on the ground at the top of the tunnels. It s important to convey to children the importance of worms in maintaining healthy soil through the decomposition of organic waste and soil aeration. Worms have both male and female parts, but mate to exchange sperm. The clitellum then secretes a band of mucus that the eggs and sperm are deposited into as the worm wiggles backwards out of the mucus band. The mucus band forms an egg capsule that looks like a grain of brown rice and contains a few eggs that hatch as baby worms after two to five weeks depending on temperature. Children can search for egg capsules in worm farms; they are easy to find. Dragonflies Dragonflies are insects with three separate body parts, a head, thorax and abdomen, but are distinguished by a very long abdomen and two pairs of transparent wings. The wings are very powerful and allow them to hover, dart, glide and reverse with agility. Children in a movement group could interpret such flying movements. Dragonflies are carnivorous and catch small insects, such as flies and mosquitoes, with their strong pincers while in flight. Their large eyes dominate the head and enable them to see all around them, even behind. (Children could compare this to their own vision.) Dragonflies live near freshwater creeks or ponds, as they require water for reproduction. After mating the female lays eggs in the water or on water plants. The young nymph (or mudeye) emerges and lives in the water crawling, eating, growing and moulting. When the nymph is ready to turn into an adult it climbs out of the water onto a plant and the last moult occurs to reveal a winged adult dragon fly. Dragonfly nymphs live up to five years and can be kept for a brief period in an aquarium, but do require small live water animals such as mosquito larvae (or wrigglers) to eat. 3

4 Centipedes and Millipedes Spiders These common garden animals are often grouped together, but are very different. Centipedes have a flattened and segmented body that is reddish brown in colour. They move very quickly, a feature that enables them to catch prey. They also have poison fangs or jaws to kill their prey and for this reason handling centipedes is to be avoided. In contrast, millipedes have a rounded and segmented body that is black in colour. Millipedes are slow moving herbivores and graze on dead plant material. They are easy to handle and will often curl into a spiral shape or create a tickling sensation on your hand. Using a magnifier it is easy for children to observe the legs, segments and antennae. Millipedes could be kept briefly in an appropriate container for observation. Centipedes do not have one hundred legs and millipedes a million as their names suggest, rather centipedes have one pair of legs per body segment and millipedes have two pairs of legs per body segment. This could be explored further with children as a mathematical experience, matching the right number of legs to each body segment on a millipede or centipede model. Spiders are not insects. They are however animals without backbones and with jointed legs so belong in the same large group. Insects have a body with three parts and six legs and the adult usually has four wings. Insects usually undergo complete or partial metamorphosis in their life cycle. (See the section on moths and butterflies.) Spiders have a body composed of two parts the cephalothorax and the abdomen. Children typically draw spiders with one body part. It is important that we help them observe live animals closely whenever possible. Spiders have eight walking legs attached to the cephalothorax, as well as palps and fangs near the mouth for manipulating food and injecting venom. Most spiders have eight simple eyes. All spiders produce web through the spinnerets at the rear of the abdomen. Not all spiders use webs to trap prey. Some, such as huntsman, pounce on their prey. Spiders only eat live prey, typically insects and other spiders. Spiders never have wings or antennae or undergo metamorphosis. All spiders produce venom to kill their prey. Mostly this is not potent enough to harm humans though, in a few species such as the Sydney Funnel Web spider the venom can be potentially fatal. In Melbourne a spider bite is more likely to produce some local irritation and discomfort or cause a problem because of the bacteria from soil that the bite introduces. The Red back spider is featured in the Children s museum. This is potentially dangerous for children (though the last known death was almost 50 years ago). These spiders live around our houses and sheds, under seats, in pots and so on. They make an untidy web which they don t often leave. The female has the characteristic red markings on the abdomen and is bigger and much more venomous than the male. Adults should be careful when moving equipment outdoors that has been there for sometime, and also model glove wearing when cleaning up areas of rubbish. There are many small spiders from the playground that children can observe for a short time. To see a spider in the process of making and lowering itself on a web is a wonderful experience for young children. Children should not handle spiders as a few can be dangerous and just as importantly because spiders are fragile children will damage them. It is hard to keep spiders successfully in captivity because they only eat live food. 4

5 Metamorphosis Many insects such as butterflies, moths, bees, ants and beetles go through complete metamorphosis. That is a larva stage (which is the eating growing stage) rests as a pupa and then emerges as the adult insect which looks quite different to the larval stage and is the reproductive part of the life cycle. The concept of metamorphosis is fascinating for children. Many great picture books bear witness to this. With butterflies and moths the larva is referred to as a caterpillar. As the caterpillar grows it moults ie. its skin splits and a new larger elastic skin is underneath. It goes through several moults before it is ready to pupate. As a pupa it appears to be resting, but its body structure is being reorganised and wings are growing. A butterfly caterpillar does not surround itself with a protective covering before pupating. (Usually referred to as a chrysalis.) A moth usually makes a cocoon to surround and protect the pupa. Sometimes this is of silk, sometimes it is between two leaves. Sometimes the moth caterpillar pupates in a burrow under the ground. An adult butterfly and many moths have a roll up tongue that it can unroll to suck nectar from flowers. Children can easily see these stages in the life cycles of the Cabbage White Butterfly and the Silk Worm described below. Breeding out an unknown caterpillar that a child finds can be fun if you can establish the correct food plant. It is however much more likely to turn into a moth than a butterfly as there are many more species of moths. It may pupate for many months. The Wanderer butterfly is featured in the Children s Museum. This bright orange and black butterfly may only be seen in Melbourne every 3 or 4 years when butterflies migrate here, but is common each year in Sydney and Brisbane. The caterpillars are bright with yellow, white and black stripes. The chrysalis is green with some black and gold. This butterfly is known as a Monarch in North America. The giant model of the wanderer flapping its wings high up on the wall is for many children a lasting memory of the museum visit. Cicadas Cicadas are insects of the type that use mouthparts to suck their food. As with crickets, cicadas do not have complete metamorphosis. They spend most of their life as nymphs, which look similar to the adult cicada, but with no wings and with strong front legs for digging. They live and grow under the ground, attached to tree roots, sucking the sap. They often remain there for several years until emerging one summer night. They then crawl up a tree and as their hard skin cracks along the back, they emerge as an adult. The skins that are left are the cicada shells children find. The adults have only a few weeks of freedom to fly and mate and lay eggs, which hatch as nymphs and burrow under the ground. Slaters Slaters are actually an introduced species. They are also called Wood Lice and are thought to have come on ships from Europe in times of early settlement. They are not insects, but are more closely related to crustaceans such as crayfish and prawns, that live in the sea. They have 14 legs as adults and 12 as young. They eat decaying vegetable matter and the bacteria associated with it. Predators include birds, small lizards and spiders. They live in leaf litter and avoid drying out. They moult as they grow. Some can curl up completely for protection. These are often referred to as pill bugs. Slaters are also called butcher or butchy boys. 5