B eing uninformed could mean the difference between a job and unemployment, meeting a life partner and eternal loneliness, or even life and death. D on’t.

Being uninformed could mean the difference between a job and unemployment, meeting a life partner and eternal loneliness, or even life and death.

Don’t be that person.

Even worse you could be one of those people at the zoo telling their kid a frog is a reptile.

The Literate Person’s Guideto the Major Phyla of the Animal Kingdom

What you need to know…

• Groups of animals you need to know are in RED• Vocabulary terms are in PURPLE• Information on the yellow slides is included for

your interest and background, but you are not responsible for knowing all of it. Just read these slides and THINK!

• Use the notes template to help keep track of the terms and important information

Symmetry

There are two major ways animal body plans are arranged.

“The parts of a radial animal, such as a sea anemone radiate from the center. Any imaginary slice through the central axis divides the animal into mirror images”

“A bilateral animal, such as a lobster has a left side and a right side. Only one imaginary cut divides the animal in mirror-images halves”

From : Biology, Campell, Reese, 7th edition

No true tissue True tissue

Radial symmetryTwo tissue layers

Bilateral SymmetryThree Tissue Layers

Protostomes Deuterostomes

Now we can learn about the different phyla of the Animal Kingdom.

Currently, there are 35 agreed upon phyla in the Kingdom Animalia.

While some phyla, like the arthropods, contain as many as 1,000,000 + different species, others contain as few as 1. We are going to focus on 10 of the largest phyla containing some of

the most common animals you might encounter (or discuss at a cocktail party).

Many of the phyla we are skipping are obscure tiny marine invertebrates like …

Rotifera KinorhynchaEcotoproctaAnd the single member of the Cycliophora – a weird thing found living in the mouth parts of lobsters.

Then there are the gazillion weird worm phyla such as the phoronid worms, ribbon worms, thorny headed worms, velvet worms, and penis worms (yes, you read that right).

No true tissue True tissue

Radial symmetryTwo tissue layers

Bilateral SymmetryThree Tissue Layers

Protostomes Deuterostomes

Phylum Porifera

• Porifera, or sponges, are the earliest animals.

• They are sessile (don’t move) • They are filter feeders, pulling water in

through their pores and collecting food particles before sending the water out through the osculum (the large hole at the top).

• They lack any specialized tissue and are instead a loose collection of cells that either filter water or process nutrients.

• The cells are held together by a network of tough skeletal fibers. It is only these fibers that remain intact in a “natural” sponge you might purchase at a store.

Osculum

Species common to New England waters.

No true tissue True tissue

Radial symmetryTwo tissue layers

Bilateral SymmetryThree Tissue Layers

Protostomes Deuterostomes

Phylum Cnidaria

• Cnidaria can be found in both salt and fresh water and include jelly fish, hydra and corals and anemones.

• They have specialized tissue and radial symmetry.• Cnidaria bodies come in one of two forms: polyp

(corals, anemones and most hydra) or medusa (jellyfish).

• All Cnidaria posses cells called cnidocytes, which are cells that help them protect themselves and capture their prey. Some cnidocytes have structures that can sting while other shoot fibers or sticky substances to entangle their prey.

• While all cnidaria can capture prey, corals also get up to 80% of their energy and nutrients from symbiotic algae living in its cells called zooxanthellae.

Jellyfish Hydra

CoralsAnemones

Usually when we think of coral we think of the hard stuff we find on the beach or buy in stores.

However, when coral is alive the hard calcareous shell it makes is full of tiny live coral polyps.

Hard coral shell

Retracted polyp

Feeding polyps

No true tissue True tissue

Radial symmetryTwo tissue layers

Bilateral SymmetryThree Tissue Layers

Protostomes Deuterostomes

Phylum Platyhelminthes

• flat worms• have true tissue .• They can live in fresh and salt water as

well as damp terrestrial habitats.• Many species are free living but some

are parasites (which damage their hosts), such as flukes and tape worms.

• Flat worms can be microscopic or up to 20 meters long!

No true tissue True tissue

Radial symmetryTwo tissue layers

Bilateral SymmetryThree Tissue Layers

Protostomes Deuterostomes

Phylum Mollusca• The mollusks are a diverse group including snails, slugs, clams,

oysters, squid and octopus.• While they may appear very different, all mollusks share three

common features: a muscular foot used for movement, a visceral mass containing the organs, and a mantle: a tissue layer that encloses the visceral mass and in many species secretes a shell.

• Many mollusks feed using a file-like flap called a radula which they use to scrape algae off of rocks or grind through the shells of prey.

A snail radula

a radula seen through an electron microscope You may have seen evidence of snail radula use on the

beach – a disturbing reminder of frequent mollusk-on-mollusk violence.

We like mollusks so much because they are common in our coastal state and quite likely to show up at the other end of toothpick at a cocktail party.

So, in addition to being familiar with the phyla we are going to ask you to know a few classes of mollusks within the phyla.

Class Gastropoda: snails and slugs• The largest number of mollusk species.• Have one shell (snails) or no shell at all (slugs)• Most are algae scrapers but some are active hunters.• They live on land as well as in fresh water and marine habitats

Terrestrial snail common to New England

Tropical marine snails

Marine snails common to New England

Moon snail Common periwinkle

Oyster drill

Tropical marine slugs

Terrestrial slug common to New England

Marine snail common to Nickelodeon

Class Bivalvia: clams, mussels, scallops, and oysters• Have two shells (the latin root for shell is ‘valv’)• filter feeders – live on the sea floor or attached to rocks• have a free-swimming larval stage

Here are some species common to Maine

oyster

Steamer clam

Blue mussel

Sea scallop

quahog

Razor clam

Bay scallop

Click on to see video.

• All cephlapods are active predators• They move by jet propulsion, shooting water out of a siphon. • This groups is considered to be the most intelligent invertebrates – octopi have

been shown to solve puzzles and unscrew jars.• Known for their color changing and camoflaging abilities. • In squid and cuttlefish the external shell common to molluscs has evolved into

an internal “bone”. Octopi have lost the shell altogether.• Squirt “ink” to confuse predators and escape.• Have appendages (“legs”) – typically 8 of them

Class Cephlapoda: squid, nautilus, cuttlefish, and octopus

Chambered Nautilus

Cuttlefish octopus

Squid