Simple Animals

This video 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 molluscs, octopuses and squid. We differentiate them by the number of tissue layers they have, and by the complexity of those layers.

Complex Animals

Hank continues our exploration of animal phyla with the more complexly organized annelida and arthropoda, and a biolography on insects.