Facts About Insects and Bugs Did you know that there are many more kinds of insects on earth than any other kind of living creature? It's hard to imagine, but 95% of all the animal species on the earth are insects! Millions of insects can exist in a single acre of land! Over one million species have been discovered by scientist, and they think that there might be ten times that many that haven't been named yet! They are divided up into 32 orders, or groups of insects. The largest order is the beetles with 125 different families and around 500,000 different species. In fact, one out of every four animals on earth is a beetle. Scientist estimate 10% of the animal biomass of the world is ants, and another 10% is termites. This means that "social Insects" probably make up an incredible 20% of the total animal biomass of this planet! Insects eat more plants that any other creatures on earth. They are so important in the breakdown of plant and animal matter, that without them, we would have a world covered with dead plants and animals. In addition to all of this, insects are a major food source for many other animals. Insects are incredibly adaptable creatures and have evolved to live successfully in most environments on earth, including deserts, and even the Antarctic. The only place where insects are not commonly found is in the oceans. Insects have an amazing number of differences in size, shape, and behavior, but they all have 4 characteristics in common. All insects must have: * Three body parts - a head, thorax and abdomen * Six jointed legs * Two antennae to sense the world around them * An exoskeleton (outside skeleton) If all four of these things are not true, then the animal can't be called an insect! Spiders are not insects because they have eight legs and don't have three body parts. Centipedes and millipedes have way too many legs to be called insects! Most insects have one or two pairs of wings, but wings aren't necessary to be classified an insect. Scientists believe that insects are so successful because: * They have a protective shell or exoskeleton * They are small * Most of them can fly Their small size and ability to fly helps them to escape from enemies and travel to new environments. Because they are small they need only small amounts of food and can live in very small cracks and spaces. Insects can also produce large numbers of offspring very quickly. Insects are directly useful to humans by producing honey, silk, wax, and other products. They are also important as pollinators of crops, natural enemies of pests, scavengers and food for other creatures. At the same time, insects are major pests of humans and domesticated animals because they destroy crops and carry diseases. Actually, less than one percent of insects species are pests, and only a few hundred of these are consistently a problem. INSECT ANATOMY Insects have a lightweight, but strong exterior (outside) skeleton called an exoskeleton. Their muscles and organs are on the inside. This multi-layered exoskeleton protects the insect from the environment and natural enemies. The exoskeleton also has many sense organs for sensing light, pressure, sound, temperature, wind and smells. Sense organs may be located almost anywhere on the insects body, not just on the head. Insects have three main body parts: Head, Thorax, Abdomen. The head is used mainly for eating, sensing things and gathering information. Insect mouth-parts have evolved for chewing (beetles,caterpillars), piercing-sucking (aphids, bugs), sponging (flies), sucking (moths), rasping-sucking (thrips), cutting-sponging (biting flies), and chewing-lapping (wasps). That's a lot of ways to eat! All insects have two antennae that they use to sense the world around them. Whether their antennae are short, long, thick, thin, insects use them to feel, smell and even taste! The thorax protects the body and gives support for three pairs of jointed legs and, on many insects, for one or two pairs of wings. The legs may be adapted for running, grasping, digging, or swimming. The abdomen contains the organs used for digestion and reproduction. INSIDE THE BODY OF AN INSECT The inside of an insect's body has an open circulatory system. That means that its body fluids just sort of flow around inside the exoskeleton. It also has many breathing tubes, and a digestive system. It has a heart, a few blood vessels, and insect blood simply flows around the body cavity. Air enters the insect through a few openings in the exoskeleton called spiracles. From there oxygen gets to all areas of the insect's body through the breathing tubes, which go everywhere in the body. The insect "stomach", or digestive system, is long and tube-like, and is usually divided into three sections. The insect nervous system send messages from the sense organs ) sight, smell, taste, hearing, and touch) to and from the brain. The brain is located in the head and processes information, but some information is also processed at nerve centers at different places in the body. INSECT GROWTH AND DEVELOPMENT (METAMORPHOSIS) Insects usually go through four separate life stages: egg, larva or nymph, pupa, and adult. Eggs are laid one at a time or in masses, in or on plants, or even inside another insect! Eventually a larva or nymph emerges from the egg. There are usually several larval or nymphal stages, called instars. During each stage the nymph grows larger and molts, or sheds its outer skin before the next stage. They grow the most during the last one or two instars, or stages. All the growing happens during the larval or nymphal stages. The eggs, pupae, and adults don't grow in size. The two types of metamorphosis typical of insects are: incomplete metamorphosis (egg--> nymph--> adult) and complete metamorphoses (egg--> larva--> pupa--> adult). INCOMPLETE METAMORPHOSIS With incomplete metamorphosis, the nymphal stages look like the adult except that they don't have wings, and the nymphs may be colored differently than the adults. Nymphs and adults usually live in the same kind of habitats. Incomplete metamorphosis is typical of true bugs and grasshoppers: complete metamorphosis is typical of beetles, flies, moths, and wasps. the young insects that go through complete metamorphosis do not look like the adults, they often live In different habitats, and feed on different things. Some moth and wasp larvae weave a silken shell (cocoon) to protect the pupa. In flies, the last larval skin becomes a puparium, a kind of hard shell, that protects the pupa. Insects are cold-blooded, so the rate at which they grow and develop depends on the temperature of their environment. Cooler temperatures cause slow growth; higher temperatures speed up the growing process. If a season is hot, more generations, or life cycles, might happen than during a cool season. Facts About Insects and Bugs Night butterflies have ears on their wings so they can avoid bats. Monarch caterpillars shed their skin four times before they become a chrysalis, growing over 2700 times their original size. There may be as many as 3,000 different kinds of insects — more than all the other animal and plant species combined. Of the huge numbers of insects, only a tiny amount, one percent, are harmful to humans. Most insects are harmless or actually beneficial. For example, without bees to pollinate flowers, plants would not have a way of reproducing and we wouldn’t have anything to eat! Locusts can eat their own weight in food in a day. A person eats his own body weight in about half a year. The earliest fossil cockroach is about 280 million years old 80 million years older than the first dinosaurs! The desert locust is the world’s most destructive insect. It can eat it’s own weight in food every day. Large swarms can gobble up to 20,000 tons of grain and plants in a day. The honeybee has to travel an average of 43,000 miles to collect enough nectar to make a pound of honey! Out of every 1,000 Mosquitoes , one female carries a disease that could be fatal to humans. Honeybees have hair on their eyes. The average housefly lives for one month. There is only one insect that can turn its head — the praying mantis. A slug has four noses. Some male spiders pluck their cobwebs like a guitar, to attract female spiders. A mosquito flaps its wings 500 times a second. Only male crickets can chirp. Baby robins eat 14 feet of earthworms every day! About 80% of the Earth’s animals are insects! The common garden worm has five pairs of hearts. Dragonflies can fly up to 50 miles per hour. The praying mantis is the only insect that can look behind its shoulders. One kind of insect called a spittlebug, lays its eggs in a big nest of saliva bubbles. I guess no predator would look for a meal in there! A snail can sleep for 3 years straight! The heaviest insect in the world weights 2.5 ounces. A cockroach can live for up to 3 weeks without its head! A butterfly has its taste receptors in its feet! The mayfly only lives for 8 hours! The female black widow’s poison is 15 times deadlier than a rattlesnake’s! There are worms in Australia that are over 4 Feet Long! The weight of all the termites in the world outweigh the weight of all humans 10 to 1! The following questions were answered by zoo biologist Ellen Dierenfeld and entomologists John VanDyk and Steve Kutcher. Q: Is there a difference between an insect and a bug? A: Yes, there is a difference. A bug is a certain type of insect. Some examples you might be familiar with are the boxelder bug, milkweed bug, assassin bug, and stink bug. True bugs have a stylet (a mouth shaped like a straw) that they use to suck plant juices from plants. The assassin bugs use their stylets to suck blood from other insects. The front wings of true bugs are thickened and colored near where they are attached to the insect's body, and are clearer and thinner towards the hind end of the wing. The hind wings are usually clear and tucked underneath the front wings. Q: What is the largest insect? A: In the book Beetles by Bernard Klaustnizer, there is a beetle called the South American longhorn beetle (Tytanus giganteus) that measures 25 cm! The heaviest insect is probably the African goliath beetle (Megasoma elephas), weighing up to 3.4 oz. And the longest insect is a huge stick insect (Pharnacia serritypes). The females can be over 36 cm in length!! Q: Is there an insect that is worth money? A: There are many, many insects that are worth money. For example, the pollination work done for free by insects would cost billions of dollars every year. Think about how much honey costs! Those bees are worth a lot of money. And insects like the praying mantis or ladybird beetle happily take care of eating harmful insects, saving money that could be spent on pesticides. There are also silk moths that produce silk, insects that produce shellac, and some insects that are canned and eaten! Make sure you don't let the reputation of a few harmful insects prevent you from noticing all the good ones. Q: How do insects grow? A: Insects have their skeletons on the outside, with their soft parts inside. That makes it hard for them to grow. Every time they want to become bigger, they have to break out of their skin and swell up to their new size before their new skin hardens. This is called molting. This means that once the insect is at its final size (adult form), it can't grow any bigger! So the butterflies and moths that you see flying around won't be any bigger tomorrow than they are today! Q: What do insects eat? A: Just about anything! There are so many different insects and each one may eat something different. Lots of them eat plants. Some of them eat other insects. Some of them eat blood (like mosquitoes). Nectar from plants is also a popular food. And many insects (like cockroaches or ants) will be happy to polish off that cookie you dropped on the floor! Q: What's the most poisonous insect? A: According to the University of Florida Book of Insect Records, the most poisonous insects are in the order Hymenoptera (wasp, bees, and ants) and the ones with the most toxic venom are certain harvester ants. Q: What's the fastest insect? A: Sphinx moths, or hawk moths, have been measured at 53 km/h. However, a horsefly (Hybomitra hinei wrighti) was recently clocked at 145 km/h! More research needs to be done in order to determine the fastest insect. Insects rule the world !