Heterodontosaurus (meaning different toothed lizard) is a genus of small herbivorous dinosaur with prominent canine teeth which lived in the Early Jurassic of South Africa.nother feature is the specialization of teeth which gave rise to the animal's name. Most dinosaurs (and indeed most reptiles) have a single type of tooth in their jaws, while Heterodontosaurus had three. At the front of the jaw beside the beak were small teeth likely used for chopping off leaves and stems.
Hypothyroidism, or low thyroid and sometimes hypothyreosis, is a common disorder of the endocrine system in which the thyroid gland does not produce enough thyroid hormone. It can cause a number of symptoms, such as poor ability to tolerate cold, a feeling of tiredness, and weight gain.
1 Hashimoto's thyroiditis (Hashimoto's disease) is an autoimmune disease in which the body's immune system attacks the thyroid gland.  Hashimoto's thyroiditis is a common cause of hypothyroidism.