Scientists do believe that Dinosaurs are the part of avian species. Especially Chickens are the probable group they actually used  to belong.

Tyrant Chicken King Doctor Jack Horner, who served as the inspiration for Doctor Grant in Jurassic Park, discovered a T. Rex femur bone in Montana in 2003.

Bones Researchers found no chicken-like tube pattern in the bones of birds when studying them.

Eggs Despite the fact that the fossil record is lacking, scientists are very certain that all dinosaurs deposited eggs.

Feathers Despite the fact that the fossil record is lacking, scientists are very certain that all dinosaurs deposited eggs.

Feet If you looked at the dinosaurs' feet, you could also see how similar they were to chickens.

Parenting Like a mother Dinosaur, a hen will teach her chicks how to scratch for food and water, keep them safe from harm, and keep them warm.

Color Feathered dinosaurs might have been as garish as contemporary birds. Melanosomes can be found in petrified feathers, therefore we know this.

Air Sacs You might have noticed that a chicken is lighter than it should be if you've ever picked one up because of the air sac.  Dinosaurs also had these.

Wings Because their predecessors were leaping into the air to grasp items above them, chickens developed short forearms to capture little prey.

Tooth or Beak? The phrase "rarer than a hen's teeth" refers to the lack of teeth in chickens. So similar with the ancient creature, isn't it?