How did researchers prove that some genes needed for tooth development are still present in chicken and that all it takes for teeth-like structures to be formed is the expression of a regulatory gene

Human Tooth Development

Explanation:

The  development of tooth  is commonly divided a some  stages such as the arrange, the bud stage ,initiation , the ringer arrange, finally maturation and the top stage.These teeth don't get through at this early stage, yet they've just shaped in uteroAfter the infant is conceived, the enjoyment starts. By and large, teeth emit somewhere in the range of 4 and 6 months of age. The enamel organ otherwise called the dental organ, is a is a cellular aggregation found in a creating tooth and it lies over the dental papillaThe dental follicle, otherwise called dental sac, is comprised of mesenchymal cells and filaments encompassing the veneer organ and dental papilla of a creating toothThey form into the alveolar bone, the cementum with Sharpey's strands and the periodontal tendon filaments separately

This is the most closely resembles the model.