In the environmental context, "fossil" generally refers to the remains or impressions of prehistoric organisms, such as plants and animals, that have been preserved in rock or sediment. Fossils can provide important information about the evolution and history of life on Earth, as well as about past environmental conditions.

Here are some examples of fossils in the environmental context:

1. Dinosaur fossils: The preserved bones, teeth, and other remains of these extinct reptiles provide important clues about their anatomy, behavior, and evolution.

2. Plant fossils: The remains of ancient plants, such as ferns, trees, and mosses, can reveal information about past climates, ecosystems, and the evolution of plant life.

3. Insect fossils: The preserved exoskeletons of ancient insects can reveal information about their anatomy, behavior, and the evolution of insects.

4. Ammonite fossils: The spiral-shaped shells of these extinct marine creatures provide important information about the evolution of cephalopods and past ocean conditions.

5. Petrified wood: Fossilized wood that has turned to stone over time, often preserved in volcanic ash or sediment, can provide information about ancient forests and climate conditions.