For generations, science fiction has imagined what life might look like on other worlds.
一代代科幻作品都在畅想其他星球上的生命形态。
Novelist H.G. Wells described nightmarish squid-like Martian invaders in The War of the Worlds, while the Superman franchise envisioned enhanced humanoid aliens. Today’s blockbusters have put forth everything from the hand-like “heptapods” of Arrival, to a territorial saucer in Nope, to the crablike extraterrestrials² that must join forces with humans in Project Hail Mary.
小说家 H.G. 威尔斯在《世界大战》中描绘了形如乌贼、样貌可怖的火星入侵者，《超人》系列则构想了体能强化的类人外星生物。如今的院线大片塑造了形形色色的外星形象：《降临》里手部造型的七肢桶、《不》中占有领地的飞碟，还有《挽救计划》里需要和人类联手的蟹形外星人。
These aliens are fictional³, sure, but some of them are informed by real evolutionary processes on Earth. That’s why, despite the immensity⁴ of space, some scientists argue the best place to begin the search for aliens might be right here at home—on the only planet we know for certain hosts life.
这些外星人固然都是虚构的，但部分形象取材于地球真实的演化规律。正因如此，尽管宇宙浩瀚无垠，不少科学家提出，探寻外星生命的起点或许就在地球 —— 这颗人类唯一确认存在生命的星球。
Scientists from a variety of backgrounds are refining the search for extraterrestrials through the lens of Earth’s most intriguing terrestrials, from miniature microbes to massive marine mammals. They argue that our fellow Earthlings can help us understand how life could potentially emerge⁵ and survive in the galaxy’s most extreme⁶ environments. These animals may even offer hints as to how we might communicate with intelligent alien civilizations⁷.
不同领域的科学家以地球上极具研究价值的本土生物（从微型微生物到巨型海洋哺乳动物）为参照，优化对地外生命的搜寻工作。他们认为，地球生物能帮助人类探明生命如何在星系的极端环境中诞生与存续，甚至能为人类和高智慧外星文明的沟通方式提供线索。
(What if aliens exist—but they’re just hiding from us? The Dark Forest theory, explained.)
（倘若外星生命真实存在，却刻意躲避人类？详解黑暗森林法则。）
Perhaps most importantly, turning our lens to our fellow Earthlings may open our minds to the possibility that aliens may not look or sound or behave like anything even the most creative science fiction writers have ever dreamed.
或许最为关键的是，研究地球生物能拓宽人类的认知：外星生命的外形、发声方式与行为模式，或许完全超脱最富想象力的科幻作家的构想。
