Life Begins
      It is theorized that the earth was formed about 4.5 billion years ago with no life forms. About 3.7 billion years ago,  microbes which need no oxygen came into existence and then about 2.4 billion years ago cyancbakteria were formed and they began to create some oxygen.
    After this some cells began to combine and these combinations, using more oxygen, eventually about 700 million years ago, created sponges which were the first living animals.
     After about another 200 million years these animals began to have heads and tails, which allowed them to begin to move in some linear direction. From this stage onwards  there were a lot of changes and more complicated life forms emerged.
       In the 1850s, a biologist Charles Darwin advanced a theory of change (evolution) based on “survival of the fittest.” This theory of how all living things descended from a common ancestor has often been misinterpreted. This theory was a strictly descriptive theory as to how evolution (change) has occurred, but it is very often described and interpreted, as if there is some type of goal in evolution.
     Darwin’s theory is based upon the fact that reproduction of living things, whether unisexual or bisexual, is not a reproduction of identical things. Rather that there is always something that is not identical, usually very, very small characteristics that may make little or no difference in how the thing looks or behaves. However, over time these small changes may multiply and/or enlarge and make a difference.
        Darwin’s theory is that some of these new things have characteristics that make them better adapted to the environment which is constantly changing, and therefore these things are the fittest and survive better than the older things. Darwin’s theory does not imply that things have a goal of becoming “better” or fitter, but merely that those that are fittest are most likely to survive.
        Some things, such as trilobites, dominated earth for millions of years, but later disappeared. Dinosaurs probably first appeared about 240 million years ago. While most dinosaurs disappeared many million years ago, we still have a few birds in the dinosaur family.
     Of more modern interest is some concrete evidence of the existence of some animals a few million years ago that later developed into Homo Sapiens. Even here there is a tremendous amount of theory and guesswork based on a few bones here and a few bones there, coupled with theories as to how different materials change over time in different conditions.
    However, the experts believed that the forebears to Homo Sapiens were some species of monkeys/apes. Even here there is a complete lack of clear evidence. Many anthropologists believe that a few million years ago Homo Sapiens’ ancestors swung down from the trees and went out into the desert and open plains where they started to walk upright and lost their fur. Here, the male hunter was the source of invention and determined how the Homo genus developed. Most of these theories are based on a few bones that have been found in different areas, buried at different depths. Then using methods of analysis based on depth, type of rock, etc. and theories as to changes over time, scientists have built theories of development and theories of evolution. Again these more modern methods of dating skeletons and tools, I leave to later sections on technological development.
     Here, however, there is an extra major problem concerning the time period (a million years or so) just before the appearance of the homo genus. During these years, insufficient bones (and/or tools) have been found for indications/evidence of the first homos to support any theory as to in what order, or why, the change occurred from a four-legged hairy ape (or perhaps a chimpanzee?) to a bipedal hairy ape (Australopithecus – 4 million years ago) and then to a hairless two-legged homo about 2-3 million years ago.
   In 1924 in south Africa a skull was found that became classified as an Australopithecus about 4 million years old. During the following 150 years many more specimens were found that were classified as Australopithecus which were eventually assumed to evolve into homo erectus.
     It would seem, however, that (almost out of nowhere) 2.5 million years ago Homo Neanderthalensis went north to Europe and western Asia, Homo Rudolfensis stayed in east Africa, and Homo Erectus migrated to east Asia. Eventually those first two homo branches disappeared and after about 2 million years even Homo Erectus probably disappeared. While the above homos were migrating, evolving and eventually disappearing, a number of other species of homos appeared and disappeared in East Africa. Among these that appeared was the species of Homo which is still in existence today, after further evolving into Homo Sapiens after another 100,000 years or so.
     It is not surprising that original evolutionary theory, especially concerning Homo Sapiens, was andocentric, since most scientists were men. The theory, concerning this time period of 1-2 million years with no physical evidence (between Australopithecus 4 million years ago and Homo Neanderthalensis 2.5 million years ago), says that some apes came out from the forest to the plains, and, during about a million years, developed into a Homo, mostly because of men’s hunting. There is, however, a less accepted theory which suggests that this period of a million years or so between the Australopithecus (4 million years ago) and the first homos (2.5 million years ago) was not one in the desert and/or open plains where males were the major source of change, but rather that the ape-changing-to-homo evolution occurred in the water and that the propelling source was not male behaviour, but female behaviour.
     In this aquatic theory, it is proposed that the emerging Homos lived along a shoreline and I will discuss this theory in the coming Chapter.