They range from tropical to arctic waters. Spores Spores are the reproductive bodies of lower plants such as ferns and mosses. They vary greatly in size and appearance. Their first appearance in the Silurian provides the earliest evidence for land plants. From that time to the present, they are common fossils.
Cenozoic spores are less important than pollen for providing information about the environment.
Starfish Starfish have been present from early in the Ordovician Period until today. Related to the crinoids and blastoids, they usually have five arms, although some possess as many as 45. Many small tube feet carry them along the ocean bottom and move food towards their mouth. Bony spines embedded in their skin make up the protective skeleton. Even so, the skeletons usually break up when the animal dies, so fossil starfish are rare.