Darwinian theory was unable of explain

What happens when the existing theory is unable to explain new observation ? Give example.

The valence bond theory is unable to explain __________.

Branching descent and natural evolution are the two key concepts of Darwinian theory of evolution . Explain each concept with the help of a suitable example

According the Darwinian theory, the rate of appearance of new forms is linked to their life cycles. Explain.

According the Darwinian theory, the rate of appearance of new forms is linked to their life cycles. Explain.

The two key concepts of Darwinian theory of evolution are

Two key concepts of Darwinian theory of evolution are

Two key concepts of Darwinian theory of evolution are