INVERTEBRATESINVERTEBRATES

The Silent MajorityThe Silent Majority

Did you know?Did you know?

At least 95% of all animals on this planet At least 95% of all animals on this planet are invertebratesare invertebrates

The weight of all earthworms, insects and The weight of all earthworms, insects and spiders is 55 times MORE that that of spiders is 55 times MORE that that of humans!humans!

SpongesSponges

Scientists used to Scientists used to mistake them for plants.mistake them for plants.

The simplest The simplest invertebrate.invertebrate.

No symmetryNo symmetry Made up of two cell Made up of two cell

layers with a jelly-like layers with a jelly-like substance in-between.substance in-between.

Hollow and no bones.Hollow and no bones.

Scuba SpongeScuba Sponge

Vase SpongeVase Sponge

Yellow Finger SpongeYellow Finger Sponge

Dried SpongesDried Sponges

CnidariaCnidaria

Simple animals with a Simple animals with a sting.sting.

Australina sea wasp Australina sea wasp has enough venom to has enough venom to kill 60 people!kill 60 people!

Like the sponge, it Like the sponge, it has 2 cell layers but is has 2 cell layers but is more complex. more complex.

Has a mouth and …Has a mouth and …

Australia Sea Wasp aka Box Australia Sea Wasp aka Box JellyfishJellyfish

Sea AnemoneSea Anemone

Tealia AnemoneTealia Anemone

CoralCoral

Flat WormsFlat Worms

The simplest wormsThe simplest worms Flat, ribbon-like Flat, ribbon-like

bodies with a head bodies with a head and tailand tail

No digestive system – No digestive system – some absorb food, some absorb food, others eat food and others eat food and pass waste through pass waste through their mouththeir mouth

Marine WormMarine Worm

New Zealand Flat WormNew Zealand Flat Worm

PlanarianPlanarian

TapewormTapeworm

Round WormsRound Worms

Slender, rounded bodies with pointed endsSlender, rounded bodies with pointed ends About 2,500 species are parasitesAbout 2,500 species are parasites One-way digestive system (food comes in One-way digestive system (food comes in

through one opening, and out another) through one opening, and out another)

The follow pictures may gross you out! If The follow pictures may gross you out! If you have a weak stomach, you should you have a weak stomach, you should probably leave the room…probably leave the room…

Ew!Ew!

Double Ew!Double Ew!

HookwormHookworm

Segmented WormsSegmented Worms

The most complex The most complex wormworm

Blood travels through Blood travels through vesselsvessels

3-layer body with 3-layer body with bilateral symmetrybilateral symmetry

One-way digestive One-way digestive systemsystem

EarthwormEarthworm

LeechLeech

MollusksMollusks

Soft bodied invertebratesSoft bodied invertebrates Some live on land, others in waterSome live on land, others in water Most have bilateral symmetry and many organ systemsMost have bilateral symmetry and many organ systems Most have either one shell, two shells, or an inner shellMost have either one shell, two shells, or an inner shell

Slugs and SnailsSlugs and Snails

ClamsClams

MusselsMussels

NautilusNautilus

ScallopsScallops

OystersOysters

OctopusOctopus

SquidSquid

EchinodermsEchinoderms

Spiny-skinned Spiny-skinned animals – most with a animals – most with a star designstar design

Endoskeletons!Endoskeletons! Many move and grab Many move and grab

things with tiny tube things with tiny tube feetfeet

Sand DollarsSand Dollars

Sea StarsSea Stars

Sea CucumberSea Cucumber

Sea UrchinSea Urchin

ArthropodsArthropods

The largest invertebrate phylumThe largest invertebrate phylum Jointed legs, body divided into sectionsJointed legs, body divided into sections Some breathe with gills, others with an Some breathe with gills, others with an

open-tube breathing systemopen-tube breathing system Exoskeleton! Made of chitin!Exoskeleton! Made of chitin! We will focus on four major arthropod We will focus on four major arthropod

classesclasses

Arthropod class: ArachnidsArthropod class: Arachnids No antennaeNo antennae Four pairs of legs, two Four pairs of legs, two

section body, up to 8 section body, up to 8 eyeseyes

Lives in a variety of Lives in a variety of habitatshabitats

Most are hunters that Most are hunters that eat insectseat insects

Many are poisonous!Many are poisonous!

MitesMites

TicksTicks

Daddy-longlegsDaddy-longlegs

SpidersSpiders

ScorpionsScorpions

Everyone’s Favorite ArachnidEveryone’s Favorite Arachnid

Arthropod Class: Arthropod Class: CrustaceansCrustaceans

Jaw-like structures for Jaw-like structures for crushing food and crushing food and chewingchewing

Two pairs of antennae for Two pairs of antennae for sensingsensing

10 or fewer legs, 10 or fewer legs, including clawsincluding claws

Sectioned bodySectioned body Some live on land and Some live on land and

others in waterothers in water Eat dead animal remains, Eat dead animal remains,

seaweed, other leftoversseaweed, other leftovers

CrabsCrabs

LobstersLobsters

Shrimp Shrimp

Barnacles Barnacles

Crayfish Crayfish

Sow BugsSow Bugs

Arthropod Class:Arthropod Class:Centipedes and MillipedesCentipedes and Millipedes

Their names can confuse you!Their names can confuse you! Both have long, thin, segmented bodiesBoth have long, thin, segmented bodies Centipedes have one pair of legs per Centipedes have one pair of legs per

segments, millipedes have two.segments, millipedes have two. Millipedes’ legs move in a wave-like Millipedes’ legs move in a wave-like

motionmotion

CentipedesCentipedes

MillipedesMillipedes

Arthropod Class:Arthropod Class:InsectsInsects

Head has one pair of Head has one pair of antennaeantennae

Three pairs of legs; one Three pairs of legs; one or two pairs of wingsor two pairs of wings

3 body sections: head, 3 body sections: head, thorax, abdomenthorax, abdomen

Eats other animals and Eats other animals and plantsplants

Special tube system for Special tube system for breathingbreathing

Compound eyes made of Compound eyes made of hundreds of lenseshundreds of lenses

BeetlesBeetles

FliesFlies

Bees Bees

AntsAnts

MosquitoMosquito

Butterflies Butterflies

Dragonflies Dragonflies

Fleas Fleas

TermitesTermites

CockroachCockroach

The Coral ReefThe Coral Reef

Another Coral ReefAnother Coral Reef