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.
By Bob Strauss. Ask the average person (or high schooler) on the street, and heâll guess that the first mammals didn't appear on the scene until after the dinosaurs went extinct 65 million years ago--and that the last dinosaurs evolved into the first mammals.ozostrodon This Triassic critter may (or may not) have been the first true mammal. Fruitafossor The earliest digging mammal yet discovered. Hadrocodium This tiny mammal had an unusually large brain. Juramaia The earliest known placental mammal in the fossil record.