Young Apes Resemble Human Children

Hartmann, in his work on the Anthropoid Apes (289, p. 301), quotes, approvingly, the words of Vogt: ‘When we consider the principles of the modern theory of evolution, as it is applied to the history of development, we are met by the important fact that in every respect the young ape stands nearer to the human child than the adult ape does to the adult man. The original differences between the young creatures of both types are much slighter than in their adult condition : this assertion, ma...

 Hen's Teeth

Some atavisms can be produced in the laboratory. The most amazing of these is that paragon of rarity, hen’s teeth. In 1980, E. J. Kollar and C. Fisher at the University of Connecticut combined the tissues of two species, grafting the tissue lining the mouth of a chicken embryo on top of tissue from the jaw of a developing mouse. Amazingly, the chicken tissue eventually produced tooth-like structures, some with distinct roots and crowns! Since the underlying mouse tissue alone could not prod...