A horse with a single, shiny horn, who can fly through the air and grant your wishes. Obviously, that is fiction, but what about the narwhal, the platypus, the rhinoceros? We have no trouble conceptualizing those, but what is a narwhal but an aquatic unicorn?
And what about the platypus? A mammal that lays eggs, has a bill shaped like a serving spoon, shiny fur and webbed claws? It does seem like a monster. And when English naturalist George Shaw first held a specimen in his hands in 1799, he thought it was a monster, or rather, a hoax. This was something that was so strange and incomprehensible, that he could not believe his own empirical evidence of sight, touch, and smell (okay, that was just the smell of preservative alcohol). But beyond not being able to believe what we cannot see, this is not believing what we can see.
But can you imagine? This animal with the bill of a duck or the bill of an otter, couldn't it have included pieces from different animals, cut and reassembled by expert naturalists? This perfectly fits one of the definitions of monsters provided by Michael Dylan Foster: "assembled from the parts of other creatures, fastened together to fashion an original whole, a monster is a hybrid," (p. 23). Or rather, he continues, it is an oxymoron. And the platypus is just that: a mammal that lays eggs. Mammals can't lay eggs: anyone who passed grade school biology would know that. Except for the tiny family of Australian animals to which the platypus belongs. Hence we can imagine George Shaw's confusion.
Let's look at another example. Take Duhrer's Rhinoceros. On first glance, it looks like a perfect anatomical of a rhinoceros, but upon closer inspection you notice the seams of clothing abutting bird-like scales and an elephant's tale. He is wearing heavy armor, like a medieval war-animal. This is another monster, cut from different animals and reassambled in Duhrer's mind.
Before, narwhals, platypi, and rhinoceroses (exotic, but real, animals) had little to differentiate them from fantastic ones. In British coats of arms, you have dolphins and lions alongside unicorns: all animals the average Brit would have never laid eyes upon, whether in photography or in a zoo. Today, with National Geographic, YouTube, and travel, it's much easier to get very close to a first- or second-hand witness of animals that could never survive in our climates. But video and photography give little to ensure veracity. Doctoring a photo to look real is very easy to do. Like our naturalist George Shaw, we accept not our sensory faculties, but accept it as true only if it seems plausible and if enough people seem to agree. Now could this be very different from monsters? Foster describes that Japanese people of the past viewed Yokai with a "degree of belief," or even like a catastrophic plane crash: rare and exceptional, but nonetheless possible (12). This is true of a myriad of urban legends, or even a large number of the photos posted on Instagram that seem just a little too perfect. And so, perhaps stories of monsters are no more fabricated than the latest photo of Kim Kardashian's xxl buttocks.
Further Reading:
"Albrecht Dürer’s The Rhinoceros: the most influential animal picture ever?" The Guardian https://www.theguardian.com/artanddesign/2016/nov/11/albrecht-durer-the-rhinoceros-1515
"The Durer Rhinoceros - Masterpieces of the British Museum" YouTube https://www.youtube.com/watch?v=IPthhO4YU28
Pandemonium and Parade by Michael Alan Foster
"Why 19th-Century Naturalists Didn't Believe in the Platypus" Atlas Obscura https://www.atlasobscura.com/articles/why-19th-century-naturalists-didnt-believe-in-the-platypus