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Preparing for a Bug Safari-Insects and Plant interactions
Plants and animals depend upon each other, this is called symbiosis. There are three main types of
relationships, mutualism where both organisms benefit, commensalism where one organism benefits
but doesn’t harm the other organism and parasitism where one organism benefits, but harms the other
organism. During your bug safari, see if you can tell what kind of relationship is happening between the
insect and plants or insect and another insect.
Plant and animals interact in three common ways: food, pollination, and shelter.
1) Food: Many plants provide food for different insects for example; monarch caterpillars and
milkweed, swallowtail butterflies and dill weed. Sometimes insects even provide food for plants!
Consider Venus fly traps and pitcher plants.
2) Pollination: Pollination is important to us and many other animals; without it, we wouldn’t have
any of our favorite fruits! Pollination occurs when pollen is taken from flower to flower; this may
eventually lead to fruit and seed development. Often pollinators have a very specific
relationship with their plants – some animals prefer certain shapes, colors, and smells of
flowers, so we can guess what sort of animal pollinates a plant based on these characteristics.
3) Shelter: Plants provide homes for many different animals. Ants live in rotting wood, bark beetles
live under living tree bark, and Goldenrod gall midges live in the stems of goldenrod. Shelter can
also include camouflage for example praying mantis blend into their green environment.
Insect body parts
All insects have 6 legs, but they can have many different types of legs and mouths! Insect bodies have
three parts; head, thorax and abdomen. The legs are connected to the thorax.
Mouthpart Types
• Siphoning or sucking – butterflies, moths and bees have these mouthparts to suck up liquids like
a straw; “straw” part called proboscis, curls up when not in use then extends to drink nectar and
water
• Piercing and sucking – used by mosquitoes, aphids, leafhoppers; pierces skin or stem of plants,
then sucks out blood or sap; piercing part called stylet
• Sponging – used by flies; dribble saliva over solid food to break into smaller pieces, then use
sponge to drink up smaller pieces
• Chewing – used by caterpillars, beetles, bull ants, leafcutter ants, damselflies; have two
mandibles (kind of like jaws) that can cut, tear, chew, or crush food
Leg Types
• Cursorial – most commonly thought of; long, thin segments made for running; makes hard to
catch or step on
o Cockroaches, ground and tiger beetles
• Saltatorial –for jumping; enlarged and elongated muscles to move small distances quickly;
usually found only on hind legs; “saltar”=jump in Spanish
o Grasshoppers, fleas, crickets, katydids
• Fossorial –for digging burrows; broad and flat, often with claws; usually forelegs; uncommon
•
•
o Mole cricket, cicada nymphs
Natatorial –for swimming (like “natatorium”); flat, broad, sometimes fringed with dense hairs to
act like paddles
o Aquatic beetles and bugs, ex: predaceous diving beetle
Raptorial –for hunting; long, enlarged muscles; used to grab prey and then hold it while eating
o Mantis, ambush bugs, giant water bugs
Wing Types
• Membranous – thin and usually transparent
o Bees, termites
• Halter – hind wings are extremely modified to only nibs, used for balance and direction
o All true flies (Diptera)
• Elytra – thick, hardened forewings without venation, used to protect hind wings and abdomen
while at rest, not actually used for flight
o Beetles
• Tegmina – leathery forewings used for protection, also not useful for flight
o Grasshoppers, cockroaches
• Scaly – wings are covered with scales to create color (talk about purpose of color – camouflage,
warning of bad taste, etc.), smooth wing, insulate
o Butterflies, dragonflies
Have fun observing insects in their natural environment, then gently capture to determine the leg,
mouth and wings types that give you clues to their interactions in the ecosystem. Release them when
you are done so they can continue their role in nature.