Mamalian ancestor or two survived
They appear to be guesses about the species surviving & evolving. Surviving can still be understood. It doesn't really makes sense. This is because the question of why has the evolution stopped? We still see other species who look like have evolved from Dinosaurs but we don't. There's more to it because we are also coming across huge skeletons of humans it's important to check their carbon dating too since it shed a light on when they lived. There may be species that looked like a evolving but it may be due to the habitat they were living in. For example; their level of tolerance to certain environmental conditions and their ability to protect themselves form the predators.