Explanation

Von Bear’s law The development of an organism proceeds from the general to the special forms and the embryos belonging to various classes closely resemble one another in their earlier stages but diverge more and more as development proceeds. He formulated Baer’s laws of embryology (i) General characteristics of the group to which an embryo belongs, develops before the special characteristics (ii) General structural relations are likewise formed before the most specific relations appear (iii) The form of any given embryo does not converge upon other definite forms but, on the contrary, separates itself from them (iv) Fundamentally, the embryo of a higher animal form never resembles the adult of another animal form