translation.en: On at least one, and maybe only one of those planets, primitive life evolved, which evolved over millions of years into things that walked upright and left footprints about three and a half million years ago in the mud flats of Tanzania, and eventually left a footprint on another world.
translation.zh: 在其中至少一个，或许是唯一一个行星上 初态生命诞生 它们经过几百万年的进化 学会了直立行走并且于 350万年前在坦桑尼亚的泥原上留下了脚印 直到最终 踏上了另一颗星球的表面