We have isolated around 30 or 40 strains already of unicellular eukaryotes.

Malavin：我们已经分离出大约 30 或 40 株胞真核生。

Why don't we get unicellular elephants, or blue whales, or brown bears?

为什么我们得不到胞大象、蓝鲸或棕熊？

Most unicellular reproduction is asexual, meaning one organism, on its own, can reproduce itself.

大多数胞繁殖是无性，这意味着一个生体可以自行繁殖。

But these could be the fossils of colonial unicellular organisms, bacterial mats, or something else entirely.

但这些可能是殖民地胞生、垫或其他完全不同东西化石。

Those are simple, unicellular life forms that thrive without oxygen and get energy by scavenging what molecules they find.

这些是简胞生命形式， 它们在没有氧气情况下也能茁壮成长，并通过清除它们发现分子来获取能量。

Yet even the biggest unicellular organisms have limits, and none grows nearly as large as the elephant, whale, or bear.

然而， 即使是最大胞生也有局限性，没有一种能像大象、鲸鱼或熊那样长得那么大。

If that's true, though, then there's a problem: Most unicellular life at the time was photosynthetic -- like cyanobacteria and phytoplankton – and they need light to live.

不过， 如果这是真，那就有问题了：当时大多数胞生命都是光合作用——就像蓝藻和浮游植一样——它们需要光才能生存。

In the 1940s, author Jack Williamson coined the term, " terraforming." To terraform is to create an ecosystem that supports living organisms—from large, complicated vertebrates, to simple, unicellular bacteria.

在 1940 年代，作家杰克·威廉姆森 (Jack Williamson) 创造了“地形改造”一词。地形改造就是创造一个支持生体生态系统——从大型、复杂脊椎动到简胞。

For 2 billion years, all organisms on Earth are unicellular, and they likely lived in the oceans, shielded from the hard ultraviolet light of the sun but then something remarkable happened, Photosynthesis.

20亿年以来，地球上所有生都是胞，它们很可能生活在海洋中，不受太阳紫外线照射，但随后发生了一件非同寻常事情，就是光合作用产生。

A further argument against the simple wear and tear theory is the observation that the time within which organisms age lies between a few days (even a few hours for unicellular organisms) and several thousand years, as with mammoth trees.

反对简磨损理论另一个论点是观察到生体老化时间介于几天（对于胞生甚至是几个小时）到几千年之间，就像猛犸象树一样。