Read the following statements and choose the following option: 1. By the time of 500 mya, invertebrates were formed and active. 2. Sea weeds and few plants existed probably around 320 mya. 3. Fish with stout and strong fins could move on land and go back to water 4. In 1938, a fish caught in South Africa happened to be a Coelacanth which was thought to be extinct. 5. The first organisms that invaded land were animals

Step-by-step solution

Giant ferns (pteridophytes) were present but they all fell to form coal deposits slowly. Some of these land reptiles went back into water to evolve into fish like reptiles probably 200 mya (e.g. Ichthyosaurs). The land reptiles were, of course, the dinosaurs. The biggest of them, i.e., Tyrannosaurus rex was about 20 feet in height and had huge fearsome dagger like teeth. About 65 mya, the dinosaurs suddenly disappeared from the earth. We do not know the true reason. Some say climatic changes killed them. Some say m