Question

In the fossil record, there is no evidence of anything living on land before plants. Why are plants necessary before more complicated animals can evolve?

Answer 1

Plants provide the earth with Oxygen and use the CO2 in our atmosphere to kickstart the carbon cycle. If it weren't for plants existing ages ago, earth would have no sustainable atmosphere, and would be devoid of life today. The Animalia kingdom would not have been created if plants didn't evolve first.

Answer 2

Plants are already in existence before anything living on land. Its existence is for the increase of O2 in the atmosphere of Earth and at the same time decreasing the CO2. They function to make O2 because without plants, there will be no one to produce O2. They are also needed to feed other organisms.