There has been two eons in the Earth's geologic history so far, the Precambrian eon, and the Phanerozoic eon. The eons are the basic and by far longest units on the geological time scale, spreading over hundreds of millions of years.
The Precambrian eon is the eon that starts with the formation of the Earth, up until the development of multi-cellular organisms. A very important event in this eon can be considered the formation of the Earth's oceans, which later enabled the conditions for the development of life. The organisms that dominated this eon are the one cellular organisms.
The Phanerozoic is the eon in which the multi-cellular organisms started to develop and evolve. This eon started with the end of the Precambrian eon, 543 million years ago up until the present. A very important event in this eon is the change of the composition of the atmosphere, which enabled the terrestrial life, as well as the better living conditions for the marine life. It is very hard to choose a dominant form of life in this eon, but worthy of mentioning are the plants, the sinapsids, dinosaurs, mammals, fish.
A microscope hope i helped
Because technically there is no such thing as cold
all that exists is heat
this is because heat is the rapid movement of particles, made by friction (to understand why you must delve into physics and some chemistry)
so, when you feel cold, it's really the absence of heat
so instead of "keeping the cold out", which makes no sense at all scientifically, insulation keeps the heat in.
as a side note
the feeling of cold is produced when you come in contact with an object (yes, air counts) that has less heat, or energy, than you do, You feel cold because heat (energy) from your body is being transferred to the environment. This ABSENCE OF HEAT in your body is why you feel cold
