408 million years ago. Earth’s first land plants and insects.
Between 400 and 500 million years ago, life migrated from the sea to the land. It is the origin of plants and insects.
It was necessary for both plants and animals to develop means to prevent dehydration under intense sunlight and ways to tolerate extreme temperatures.
Most probably, the first animals to come ashore and colonize the land were the arthropods, largely because they had exoskeletons.
The earliest arthropod fossil is Pneumodesmus newmani, dated 428 million years ago.
The oldest plant fossil is Cooksonia pertoni, dated 425 million years ago.