There was another major extinction event at about 65 mya when the dinosaurs died out and mammals began to flourish. What were some of the stategies used that allowed mammals to survive when dinosaurs could not?

There are several reasons for the mammals survival and the extinction of the dinosaurs. The impact of a comet striking on the earth created devastation in the environment creating massive heat, dust and lack of oxygen led to the death of these mighty creatures. Mammals might have different diets due to evolution during the Mesozoic. After the comet impact, meat immediately became a limited commodity and later, green botanic became equally hard to come by. Decaying wood was overflowing, inviting all kinds of insects and worms. Mammals found food in small creatures, while the dinosaurs were ravenous and diminished.