Dimetrodon

This is a model of a Dimetrodon. While commonly associated with dinosaurs, in reality it's actually more closely related to mammals! It lived around 295-272 million years ago, and its name means “two measures of tooth” referring to the large and small teeth. It most likely had a semi sprawling posture, like an alligator, where it could walk with its body and most of its tail off the ground, but could sprawl like a lizard when at rest, as this model depicts. The notable sail on its back may have been used to aid in maintaining body temperature, but based on the latest research is more likely to have been primarily used as a display for courtship or threatening rivals.

The model does need supports on the build plate, but otherwise should print without.