Brought to you by: Kate Lee, Beth Reinert,
Christie Currie, and Maggie Gorski
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Segmented animals
Five subphylums: Trilobita, Cehelicerata,
Crustacea, Myriapoda, and Hexapoda
Arthropods include insects, spiders, trilobites,
shrimp, lobsters, crabs, etc.
Evolved around 545 million years ago around the
same time as chordates evolved
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Bilateral symmetry
Coeloms
Uses exoskeletons for structure and support
Exoskeleton has three layers and the tough
covering is called the carapace.
Most arthropods shed their exoskeleton through a
process called molting.
•Macrocheira
kaempferi
(Japanese Spider
Crab)
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Reproduce sexually through internal
fertilization
Aquatic crustaceans use swimmerets that
transfer sperm to egg.
The eggs then hatch into a free-swimming
larva called a nauplius
Through many series of molting, the nauplius
eventually develops into the adult form
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Food passes through a one way digestive
tract (mouth to anus).
Uses a digestive gland to mix food with
enzymes
Excess water and wastes are eliminated using
green glands.
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Open circulatory system
uses hearts and vessels to transport
circulatory fluid throughout the crustacean
Uses gills to exchange oxygen and carbon
dioxide for respiration
Nervous System
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has clusters of ganglia in the brain that
controls the body (cephalized)
Ganglias throughout the body are connected
by a ventral nerve cord
Tissues include heart tissues,
nerve tissues, and gill tissues.
Crustaceans use sensory hairs that
sense vibrations and chemicals
 Can be terrestrial or aquatic
 Some crustaceans are up to 4 meters
long
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The goose barnacle
(Lepas anatifera) is
an aquatic
crustacean.
Insecta
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Order Hemiptera (“half
wing”); true bugs
Order Homoptera (“like
wing”); aphids, mealy bugs,
cicadas
Order Isoptera (“equal wing”);
termites
Order Odonata (“toothed”);
dragonflies, damselflies
Order Orthoptera (“straight
wing”); grasshoppers,
crickets, katydids
Order Coleoptera (“sheathed
wing”); weevils, ladybugs,
beetles
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Order Coleoptera
(“sheathed wing”);
weevils, ladybugs,
beetles
Order Diptera (“two
wing”); mosquitoes, flies,
gnats
Order Hymenoptera
(“membrane wing”); bees,
wasps, and ants
Order Lepidoptera
(“scaled wing”);
butterflies, moths
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Bilateral Symmetry
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The body of an insect is divided into three
tagmata: the head, thorax, and abdomen.
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Brain, Crop, Aorta,
Gastric Ceca, Ovary,
Heart, Tracheae, Anus,
Oviduct, Seminal
Receptacle, Hindgut,
Malphigian tubules,
midgut, Ganglion,
Ventral Nerve cord,
gizzard, salivary
glands, and the
esophagus.
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Characteristics of
most insects: a
body consisting of
a head, thorax, and
abdomen; a pair of
unbranched
antennae; three
pairs of jointed
legs; and two pairs
of wings.
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One way digestive tract
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Malphigian tubules
which collect water and
cellular wastes from
the hemolymph and
produce a very
concentrated mixture
of wastes that is
deposited in the
hindgut and leaves the
body with the feces.
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Open circulatory system
Insects exchanges oxygen and carbon
dioxide with the environment through a
complex network of air tubes called trachea.
Reproduction & Development
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All insects have separate sexes and reproduce
through internal fertilization
Develop either through incomplete metamorphosis
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Or incomplete metamorphosis
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Consists of a brain and a ventral nerve cord with ganglia
located in each body segment.
Antennae contain sensory structures that respond to touch
and smell.
Three simple eyes function to sense the intensity of light
Two bulging compound eyes provide a wide field of view
and can detect movement and form images.
The tympanum detects sounds
Sensory hairs detect touch or movement by vibration
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Insect
defense:
warning
coloration,
Müllerian
mimicry,
Batesian
mimicry,
venomous
stingers,
spraying
noxious
chemicals
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Insects communicate
through pheromone,
sound, and light.
Bee Dances
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The Round Dance
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The Waggle Dance