A fire retardant is a substance that reduces flammability of fuels or delays their combustion. This includes chemical agents, but may also include substances that work by physical action, such as cooling the fuels, such as fire-fighting foams and fire-retardant gels.
These early mammals were small, insectivorous, nocturnal, hairy and warm-blooded. Warm-bloodedness is believed to have first evolved among the cynodonts, a late but successful group of mammal-like reptiles from which the mammals evolved.he Mammal-like Reptiles, or Therapsids first appeared about 285 million years ago near the begiining of the Permian which is well before the dinosaurs. They evolved quickly and many different groups arose.
All animals, from sponges to jellyfish to vertebrates [animals with a backbone], can be traced to a common ancestor. So far, molecular and fossil evidence indicate that animals evolved at least 600 million years ago. The fossil record does not reveal what the first animals looked like or how they lived.