Beef should be aged a few days before cutting. The amount of aging will depend on the amount of fat covering, desired flavor and temperature. Carcasses that have only a thin fat covering should be aged three to five days; those with more fat, five to seven days. Very little tenderization occurs after seven days.
Ask your average paleontologist who is familiar with the phylogeny of vertebrates and they will probably tell you that yes, birds (avians) are dinosaurs. Using proper terminology, birds are avian dinosaurs; other dinosaurs are non-avian dinosaurs, and (strange as it may sound) birds are technically considered reptiles.
Some  amphibians have a rough leathery skin.  Reptiles are generally bigger in size than amphibians.  Reptiles include four groups of animals-lizards and snakes,  turtles and tortoises, crocodilians, and tuatara. Amphibians  include three groups of animals-frogs and toads, salamanders and  caecillians. Different species of reptiles live on land, in water, or both  on land and in water. However, all amphibians are born in water and  spend early part of their lives in water in form of larvae. Through  a process of metamorphosis the larvae of amphibians grow into  adults which are quite different from the larvae.