>>13285487Asteroid caused a mass extinction of plants, killing all herbivores. Meat and eggs became the primary sources of food. Carnivorous/omnivorous dinosaurs couldn't protect their eggs well enough, and the eggs took too long to hatch due to having teeth, and thus their eggs got eaten.
Mammals develop in the womb so they didn't get egg poached. Birds hid their eggs, had a much faster hatching speed due to beaks, and could search for food well, so they also survived. A lot of birds at the time were also semi-aquatic like ducks, so they likely could have subsisted off of the same food supply that kept crocs and turtles alive.
