Imagine you go to a zoology conference. The first speaker talks about her 3D model of a 12-legged purple spider that lives in the Arctic. There’s no evidence it exists, she admits, but it’s a testable hypothesis, and she argues that a mission should be sent off to search the Arctic for spiders.
The second speaker has a model for a flying earthworm, but it flies only in caves. There’s no evidence for that either, but he petitions to search the world’s caves. The third one has a model for octopuses on Mars. It’s testable, he stresses.
