The large Plesiosaur (sea reptile) that eats Pod's mate is erroneously shown being able to rear its long neck back like a swan and strike at its prey. In real life, the necks of such animals were quite stiff, and they also preyed upon small fish, rather than dinosaurs.
Magyarosaurus is shown chewing its foot. It couldn't. Instead, it let the pebbles in its stomach break down plant matter for it.
The puppet of Pod's head has a lot of excess rubber around its eyes.