Decades: 370s BC 360s BC 350s BC 340s BC 330s BC - **320s BC** - 310s BC 300s BC 290s BC 280s BC 270s BC

325 BC 324 BC 323 BC 322 BC 321 BC - **320 BC** - 319 BC 318 BC 317 BC 316 BC 315 BC

- Theophrastus begins the systematic study of botany.
- Zhou Shen Jing Wang becomes King of the Zhou Dynasty of China.