Transcript Bugs of the Bay

Bugs of the Bay
What is a bug?
•Bugs come in many shapes and sizes
•Bugs have some similarities and
differences
•There are three main categories of
bugs:
Insects,spiders, and myriapods
•Insects
have distinctive features that
help us identify them.
•Arachnids
We’ll talk mostly about insects
•Myriapods
and arachnids today.
What are insects?
?
•Insects are animals that lack a backbone
•All insects have
•a hard exoskeleton
•a three-part body (head, thorax, and abdomen)
•three pairs of jointed legs
•compound eyes
•two antennae.
•legs (and wings, if applicable) are attached to the
thorax
•Insects breathe through holes called spiracles
•Insects hatch from eggs.
•There are about a million different types of insects
and many more that have not been discovered yet.
How can you identify
an insect?
Ants
Lady Bugs
Brine Flies
Mosquitoes
Darkling Beetles
Monarch Butterflies
Yellow Jackets
Dragonflies
What are spiders?
•Spiders belong to a group of animals called
“arachnids” Scorpions, mites, and ticks are
also part of the arachnid family
•Spiders have:
•two body segments,
•eight legs,
•no wings or antennae
•are not able to chew
•All spiders are predators and many will eat
other spiders
How can you identify
a spider?
Orb Spider
Black Widow Spiders
What is the difference
between insects and spiders?
•How the spider differs from the insects:
•How many legs does an insect have? Let’s
count to see how many legs the spider has.
•How many body parts does the spider have? How
many body parts does an insect have? Which one
has more?
Insect
or
Spider
What are the life cycles
(metamorphosis) of bugs?
?
•Bugs change shapes by metamorphosis
•Complete metamorphosis – young look
very different from the adults
(caterpillars are young that turn into
butterflies)
•Incomplete metamorphosis – only change
is in size as the young molt (shed their
exoskeleton) and grow a new one to
accommodate their growing body
What is the life cycle of a fly?
What is the life cycle of a mosquito?
What is the life cycle of a grasshopper?
What is the life cycle of a darkling beetle?
What is the life cycle of a butterfly?
What is the life cycle of a spider?
What do bugs eat?
• Insects
– Some
– Some
– Some
other
– Some
– Some
eat other insects
eat plants
are parasites that eat off
bugs but don’t kill them
are scavengers
eat just about anything
What do bugs eat?
• Spiders
– They are predators – they catch and eat
other animals, mostly insects
– Some spiders are big enough to catch
lizards, birds, tadpoles or fish
What good are bugs to us?
•Some insects produce valuable products: bees produce honey, and
silk worms (which are really moths) produce silk.
•Farmers need insects because without the insects many crops would
not produce fruits. The insects are needed to pollinate the crops.
Insects such as bees, wasps and butterflies visit a flower to collect
nectar. At the same time, they pick up some pollen and carry it with
them to the next flower they visit. In this way they help to crosspollinate the plant, which will then produce good fruits..
•There are many other insects that are useful to farmers because
they help control pest insects.
What good are bugs to us?
•In many countries, people use insects as food. Actually there are
hundreds of species of insects that are edible and can be eaten by
people. Some of these are collected from the wild, while others are
produced on special insect farms.
•Insects can be used as live food for many pet animals. Pet birds,
lizards and chameleons love to eat mealworms, crickets or
grasshoppers. Also for other terrarium animals and for aquarium fish
we can use insects as a healthy food.
•Insects can also be used as a fishing bait, because many types of
fish love to eat insects.
•Many insects live as scavengers and feed on dead animals. Others
feed on dead plant materials. In this way they help recycling of
biomass in nature. This recycling process helps to create fertile top
soil in which new plants and trees can easily grow.
•Examples of insects that are important in this biomass recycling are
ants, termites, flies and cockroaches. Another example of this
recycling process is the way dung beetles feed on feces. They help
recycling the dung and at the same time return nutrients to the soil.
What good are bugs to us?
•Insects are easy to rear and multiply in large numbers.
That’s why researchers often use insects to do all kind of
experiments. A very famous laboratory insects is the common
fruit fly (or vinegar fly). This insect has been studied a lot
by researchers interested in genetics.
•The beauty of insects can be best enjoyed in nature.
Especially butterflies and beetles can be very beautiful with a
large variation of patterns and colors. Many poets are
inspired by the beauty of insects and write poems about
butterflies, fireflies and other insects.
What good are bugs to us?
•Spiders do more good than harm to people.
•In North America, at least, only two kinds of spiders are truly
harmful to humans – the brown recluse and the black widow (and,
by all means, get rid of them).
•The rest actually just eat other insects we usually find pretty
scary, including mosquitoes carrying malaria (the world’s #1 fatal
disease) and flies carrying cholera.
•The presence of spiders in your house is a sign that 2,000 fewer
bugs per spider will be there every year.
•In your garden, spiders eat those bugs that love to damage your
plants! In fact, they’re used in organic cotton farming for exactly
this reason.
.
Where do bugs live?
Everywhere, even in
Antarctica, except for at
the North and South Poles
How do bugs communicate?
Have you ever heard an insect make a sound? Does a bee make a sound?
What sound does a bee make?
Explain that different insects make sounds in different ways.
They communicate without talking
•Some use special chemical odors (pheromones) to “talk” and find each
other
•Some use visual signals—like fireflies with flashing lights
•Others use sound
•They make noises (mosquitoes and bees beat their wings,
crickets and grasshoppers rub parts of their bodies together, and
cicadas contract muscles in their abdomens
•Some sing to each other
What did we learn about
bugs?