Insects, and other invertebrates outnumber vertebrates—segmented-legs down! The first in a five-part series of videos from an Invertebrates series introduces these organisms in all their spineless glory. Each invertebrate phyla takes the...

A video focusing on the evolutionary history of simple animals reveals some amazing facts. Did you know that some deep-water sponges can live to be more than 200 years old? The narrator of the film explains what simple animals...

And the prize for oldest living thing on Earth goes to . . . In this video from PBS Digital Studios, viewers learn about the oldest living things on Earth, all over 2,000 years old, such as bristlecone pines, baobab, sea grass,...

Hank introduces us to the least complex animals: beginning with sponges and finishing with the most complex molluscs, octopuses, and squid. We differentiate them by the number of tissue layers they have and by the complexity of those...

Hank introduces us to the "simplest" of the animals, complexity-wise: beginning with sponges (whose very inclusion in the list as "animals" has been called into question because they are so simple) and finishing with the most complex...

Learn about the first animal in this video. The ancient sponge appeared about 2.5 billion years ago coming in many sizes and shapes, sponge bodies are a loose assemblage of cells held together by a special protein called collagen which...

Watch as a florescent dye is injected next to a sponge and the sponge quickly pumps the dye through its body in this video. This demonstrates that sponges actively pump large quantities of water through their bodies in order to extract...

Did you know sponges are the only animals that if broken down to the level of their cells, can reassemble themselves? Watch this video as sponge is passed through a sieve to break apart its cells. Then watch as the cells recognize each...

Cristina Diaz describes her work as a taxonomist in this video. She dives in Indonesia to study her favorite animal, the sponge. Conducting an experiment to see how fast a sponge filters, she injects a colored dye into the water. The...

Spicules are microscopic structures of hard crystal material with fantastic shapes unique to the different species of sponge. They are part of the skeleton that helps give the sponge its shape. [1:59]

Along with other microscopic organisms (dinoflagellates, diatoms, bacteria, etc.), we become a tiny particle and are pulled through the canals of a sponge. Along the way we learn that sponge cells catch food and make spicules(microscopic...