Insects
Insects are the largest group of arthropods. Of the 1.5 million species of animals named by scientists, 1 million of those are insects. Scientists believe there may be from 1 to 10 million insect species still undiscovered.
Insects have unusual sense organs, most notably their eyes. Most adult insects have compound eyes, containing thousands of lenses. These unique eyes allow insects to see motion, though they cannot see details. Most insects have two antennae which they use for smelling and feeling (and sometimes tasting and hearing). Their mouthparts are specially adapted for the kinds of foods they eat, whether for chewing (beetles and grasshoppers), sucking (butterflies and moths), or piercing and sucking (mosquitoes). Insects are also the only arthropods that have wings. The thorax may have one or two pairs of wings attached to it; however, not all insects have wings.
Label the Life Cycle of the Butterfly
Insect Intellect (handout)