
Living fossils
In the oceans, there are still animals today whose ancestors existed millions of years ago. These so-called "prehistoric animals" have hardly changed over very long periods of time.
Examples from the underwater world
These species include, among others, horseshoe crabs, nautiluses, or some sharks. Their body plans have proven successful over many geological epochs, allowing them to survive to this day.
Importance for research
Prehistoric animals provide scientists with important clues about the evolution of life in the sea. By studying them, many modern animal groups' evolutionary steps can be better understood.