abdomen: The rear section of a grasshopper, house fly or other insect.

adaptation: The structures or behaviors of an organism that are suited to a parti- cular environment.

antenna: One of a pair of “feelers” on an insect’s head. (plural: antennae)

anus: The opening at the end of an animal’s digestive system where waste leaves the body.

backbone: A chain of small bones that run along the center of the back of a vertebrate. Also called the spine or spinal column.

biomechanical: The application of mechanics and machinery knowledge to the structure and functions of living things.

bone: The hard tissue that forms the skeleton of vertebrates.

brain: The organ in an animal’s head that controls and regulates the body’s activities.

calcar: A spur on the inner side of a bat’s ankle that helps support the wing membrane.

camouflage: A way of hiding by blending in with the surrounding environment.

chromatophores: Special skin cells that change a chameleon’s color.

cloaca: An organ into which an animal’s digestive, urinary and reproductive systems empty.

cold-blooded: Having a body temperature that rises or falls with the temperature of the surrounding environment.

compound eye: An eye that’s made up of many tiny, simple eyes that work together to form an image.

crop: A saclike area in an insect’s gut where food is stored before it’s digested.

digestion: The breaking down of food into forms the body can use.

echolocation: A system that bats use to navigate and find food. They give off high-pitched sounds, then interpret the echoes.

endoskeleton: A skeleton that’s inside the body (like your skeleton).

engineering: The design, construction and operation of structures and machines, using scientific principles.

esophagus: The tube that leads from the throat to the stomach or crop.

exoskeleton: The hard outer covering that makes up the skeleton of insects and some other animals.

evolution: The change in the genetic make-up of a population of organisms over time. This process of change is driven by natural selection.

feathers: A bird’s body covering. Each feather is made up of a hollow rod with two rows of light, soft barbs.

femur: The third segment of an insect’s leg; also, the thighbone or the corresponding bone of the hind limb in a four-footed mammal.

fur: The hairy coat of a mammal.

ganglia: Groups of nerve cells that act as brains in insects.

gills: The breathing organs of a water-living animal. They exchange gases between body fluids and the surrounding water.

hair: A mammal’s outermost covering, made up of threadlike growths on the skin.

horn: The hard, pointed structure that grows on the head of some animals and is used for self-defense.

humerus: The upper bone of an animal’s front leg or arm.

insect: An animal that breathes air, has an exoskeleton, three body segments, three pairs of legs, two sets of wings (usually), a pair of antennae and compound eyes.

intestines: The tube-like part of the digestive system between the stomach or crop and the cloaca or anus.

invertebrate: An animal that has no backbone.

keratin: The tough protein that makes up hair, nails, scales, horns and hooves.

labra/labia: The upper and lower plates that form insects’ lips.

larynx: The part of the respiratory (breathing) system that contains an animal’s “voice box.” The “voice box” of some animals.

machine: A human-made system or device made up of fixed and moving parts that perform tasks.

mammal: A warm-blooded vertebrate that grows hair on its skin and (in females) produces milk for its young.

mandible: One of a pair of jaws in insects and beaked animals, such as squid.

manus: The end of a squid tentacle.

maxilla: One of a pair of mouth parts located just behind an insect’s mandibles.

muscle: Body tissue made up of bundles of cells or fibers that move body parts by lengthening and shortening.

nerves: Long fibers or bundles of fibers that transmit messages between the brain and the rest of the body.

nervous system: The system of nerves, ganglia, and (in vertebrates) the spinal cord and brain. It regulates and coordinates all the body’s activities.

organism: A living being.

ovary: The organ that produces eggs in females.

pharynx: The part of the digestive tract that connects the mouth with the esophagus.

prehensile: Adapted for holding, especially by wrapping around, like a chameleon’s tail.

pretarsals: The last segment of an insect’s legs.

proboscis: A long, tube-like structure on an invertebrate’s head.

radula: The tooth-lined tongue of a squid.

reptile: A cold-blooded vertebrate that lays eggs and has scales or plates on its skin.

respiration: The interchange of gases between a cell and its environment, or between an animal and its environment (known as breathing).

robot: A mechanical device resembling a living animal that moves automatically or by remote control.

scale: One of the small, plate-like structures that cover reptiles.

skeleton: A hard structure that supports and shapes an animal.

specimen: An individual in a group, used as an example of the whole.

spinal cord: The central pathway of a vertebrate’s nervous system, it runs from the brain through the backbone.

spiracles: The opening on an insect’s sides where air enters the respiratory system.

stomach: A sac-like organ that digests food.

tentacle: One of a pair of long, thing, flexible structures that squid use to feel and to grab food.

thorax: The middle segment of an insect, where the legs and wings attach.

tibia: The fourth segment of an insect’s leg; also, the shinbone or corresponding bone in a horse or other hoofed, four-footed mammal.

trachea: A tube that carries air to the lungs (in a vertebrate) or to other body tissues (in an insect).

ultrasonic: A sound frequency that’s too high for humans to hear.

vertebra: One of a chain of bones that make up the backbone. (plural: vertebrae)

vertebrate: An animal that has a backbone.

warm-blooded: Having a constant body temperature that doesn’t depend on the outside environment.