Page 228F: Invertebrate Animals

Introduction to Porifera
Visit this site to learn all about sponges, phylum Porifera. Sponges are among the oldest living known animal fossils, dating back to the late Precambrian.

Sponges: The Weird Wonders of the Seas!
Go to this site to see a simple illustration of the structure of a sponge. Scroll down to see a photograph of the pumping action of a sponge.

Sponges – pump-filter modules through space and time…
At this site you can learn more about the structure and functions of sponges. Scroll down to read about basic sponge anatomy.

Hermit Crab Sponges
Visit this site to find out about an unusual relationship between certain species of hermit crabs and sponges. Ask students the following questions: How do sponges benefit from this association? How do hermit crabs benefit?

FAQ – Cnidarians
Visit this site by the Cnidarian Research Institute to learn all about cnidarians, including corals, sea anemones, jellyfish, and hydras. Scroll down to see an animated graphic of a nematocyst exploding. Ask students to find out how an exploding nematocyst is like a bee’s sting? (HINT: Tell them to find out how many times each of these can be used by the organism.)

Cnidaria: Life History and Ecology
At this site by the Museum of Paleontology, University of California, Berkeley you can read a brief summary of the ecology of coral reefs.

Life and Times
Go to this site by the Reef Education Network (REN) to learn about the ecology of coral reefs. You can learn about the geological history of coral reefs by clicking on origins, or about the types of reefs by clicking on reef design.

Marine Flatworms of the World
Visit this site to see photographs of the colorful marine flatworms found worldwide. Click on marine flatworms, then click on any of the geographic locations shown. For example, click on Hawaii to see images of the marine flatworms found there. Click on any image to enlarge it and find out where the photo was taken.

Wonders of the Seas: Mollusks: Snails and other weird animals
At this site you can learn all about mollusks, a group that includes snails, clams, oysters, octopuses, and squids.

Leeches to suck your blood!Visit this site to learn all about leeches and how they feed. Leeches have been used in medicine for many years.

Leeches!
Go to this site to learn more about the medicinal properties of leech saliva. The leech Hirudo medicinalis produces an anticoagulant, a vasodilator, and a local anaesthetic.?

Health Topics A-Z: Leeches
At this site you can learn about the uses of leeches in medicine. Leeches are especially useful in cases of trauma or in surgical procedures involving the reattachment of severed body parts.

Introduction to the Arthropoda…the REAL rulers of Earth…
Visit this site to learn all about arthropods, the most successful animals on the planet. Arthropods can be found on land, in the water, and in the air. There are millions of arthropod species on Earth, more than any other animal group.

Echinoderms
Go to this site to see photographs and read descriptions of sea stars, sea urchins, and a sea cucumber.

Echinoderms – The Spiny Animals
At this site you can learn more about the phylum Echinodermata, which includes about 6000 species. Scroll down to read about the holothuroids and to find out how a sea cucumber uses its tentacles in feeding.

Sea Urchin Embryology: Natural History
Visit this site to learn all about sea urchins, including their habitat, distribution, and feeding relationships. Scroll down to indicator organisms to find out how sea urchins are used by humans.

The Cephalopod Page
Visit this site to find out all about the cephalopods – octopuses, cuttlefishes, squids, and the chambered nautilus.

In Search of Giant Squid
Go to this site by the Smithsonian Institution to read about an expedition in 1999 to look for the giant squid. Scroll down and click on the creature to see how big a giant squid is.

Morphology (Physical Descriptions)
At this site you can find out more about the physical characteristics of squid. Squid, like cuttlefish, have ten arms, of which two are modified to capture prey.