Ours can be a brutal planet. 我们的星球有时候很残酷

164. the planet has pushed life to the very edge of existence.
     地球将生命推到了灭绝边缘
165. Each time, more than three-quarters of all species
     每一次 超过四分之三的物种
166. were lost in mass extinctions.
     在大规模灭绝中消失
167. Ours can be a brutal planet.
     我们的星球有时候很残酷
168. But there was one period
     但曾经有一个时期
169. when Earth was stable for 100 million years.
     地球保持了一亿年稳定状态
170. A period which allowed one group to become the mightiest of dynasties.
     这个时期 令一个物种群建立了最强大的王朝

来自《我们星球上的生命 第一季 第一集 Life on Our Planet S01E01 生命法则》第 167 行