The Ashikaga era is a part of Japanese history.

The Asuka Period is a part of Japanese history, a time when culture and arts greatly developed.

The Muromachi period is a part of Japanese history, a time when many cultural changes occurred.

The Kamakura period was a very important time in Japanese history.

Chrysophyta perform photosynthesis underwater, supplying oxygen.

Everyone, please have a good new year.

The Paleolithic is the first era of human history.

The Bronze Age was an important period in human history.

The Neolithic was an important period in human history.

The Mesolithic is the era between the Paleolithic and the Neolithic.