Weird Life: The Search for Life That Is Very, Very Different from Our Own

“Weird indeed, and not a little wonderful.”—Nature In the 1980s and 1990s, in places where no one thought it possible, scientists found organisms they called extremophiles: lovers of extremes. There were bacteria in volcanic hydrothermal vents on the ocean floor, single-celled algae in Antarctic ice floes, and fungi in the cooling pools of nuclear reactors.

But might there be life stranger than the most extreme extremophile? Might there be, somewhere, another kind of life entirely? In fact,...