translation.en: And when you look at those tiny green algae on the right of the slide here, they are the direct descendants of those who have been pumping oxygen a billion years ago in the atmosphere of the Earth.
translation.zh: 看看幻灯片右边 那些微小的绿藻， 它们是十亿年前往地球大气中 输送氧气的生物的直系后裔。 当时它们制造的氧气，