Likewise, if the population consists of equal numbers of males and females, and if the females give birth to 3 children each (and the males 0), then the average birth rate of the population will be 1.5. With these basics we can now consider two simple models of population growth:
For most purposes scrolls have long been superseded by the codex book format, but they are still produced for some ceremonial or religious purposes, notably for the Jewish Torah scroll for use in synagogues.
The Egyptians developed their own system of writing called hieroglyphics. This system was based on a series of pictures showing common objects such as a human eye. Later, a group of people known as the Phoenicians used pictures or symbols to represent sounds. This was the first alphabet.