I’ve been thinking about oddities of nature, feral children and other beings that have captured peoples’ imagination over time. I came across some illustrations by an artist who really delved into the what ifs of human and animal existence.
Fortunio Liceti published De Monstris in 1665. He held a doctorate in philosophy and medicine and was widely published. Galileo, a friend, once loaned him money.
His drawings depicted monstrosities in nature, and apparently inspired widespread interest in what ifs: mermaids, pygmies and other marvels of the natural world. What I like is that it seemed in that early time as though anything was possible. People could grow arms out of their necks.
The Public Domain Review offers quite a few of these marvels for your perusal. Here is a taste.
Jean Zimmerman 
Yes, we’re hardwired to be thrilled by monsters, I believe.
Ha. A few days ago, I thought about some odd possibilities too, very weird, as I finished reading RELIC by Preston & Child.