They later found other parts of the skeleton—
Resized to 60% of original (view original)
Now, where to put this...
However, more accurate reconstructions based on later fossils discovered ended up being totally different.
They resembled an iguana's, except tens of times bigger, so he named their owner "iguanodon" (iguana tooth).
And so, this iguanodon standing before us now
is the "nonexistent fantasy animal created by human imagination" from Mantell's reconstruction!
but they'd been scattered underground, so Mantell drew up his hypothesis of what the whole body might've looked like, based on the remaining parts and the modern iguana.
Then in the year 1822 AD a doctor named Gideon Mantell found fossils of strange teeth that didn't match any known animal.