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4.) What sounds more logical?
a.) God created life.
b.) Although Earth was created around 4.5 billion years ago, life began to exist not long after. Due to the huge timescales involved, there is inconclusive evidence for exact dates, but nonetheless, the eagerness of life to exist was apparent from the beginning. Our Solar System was still young, and the Sun was still cooling down after its creation billions of years beforehand. The unique circumstances of our Solar System and our planet gave rise to life. This was due to a number of characteristics that are exhibited by our ecosphere, the area of a planet capable of sustaining life. Venus, one of our planetary neighbors, is closer to the sun, with the planet exhibiting characteristics that would not be able to support life. On the other hand, Mars is further away from the Sun, and too cold to naturally support life. However, with manipulation by man, via terraforming, Mars could indeed support life in its present state. However, Earth, for billions of years, has possessed all the materials and suitable conditions for supporting life. All living things possess the element carbon within them. In light of this, Earth had to have rich supply of carbon to support a rich diversity of life. This carbon was made available by the volatile nature of the Earth in the beginning, where volcanoes spewed various elements into the Earth's atmosphere. While ing blocks of life. The complex organisms of today harness the biological power of proteins in a variety of ways, such as the use of enzymes as a catalyst. In general, organisms over time in the evolutionary chain have grown and become more complex in their nature, i.e. the first origins of life were likely small, simple and not diversified. One understanding of the origins of life is that it would have been very unlikely that parasites were the beginnings of life. As parasites require biological hosts to reproduce and thus survive as a species, they would have been unable to successfully continue their species during this time period. In light of this, viruses and other parasites would have developed later on in the evolutionary chain. It is believed that heterotrophs were the first beginnings of life on Earth, inhabiting the sea and absorbing the organic material that was being created by the reactions of Earth at the time (i.e. the creation of amino acids). The building blocks of life created these organisms and also acted as a food source. This is where the idea of a food chain becomes relevant. When these first autotrophs died, the organic material that they consist of would break down and add to the 'organic soup' that was feeding these organisms at the time. Alias, it is believed that heterotrophic bacteria was the first signs of life on Earth
A component of all existing life is that it adapts to survive. You either adapt or you already have adapted. If species did not have this instinctive nature via their genetic information, then they would have no desire to continue living as a species. Although the beginnings of life above were successfully reproducing, an economy of scale involving the organisms would point out that their food source (the organic soup) would not be able to sustain all life. In light of this, the organisms on Earth at the time would have to diversify over the long term to survive. It is suggested that around three billion years ago, autotrophic animals had diversified from previous species. These autotrophs are capable of synthesizing energy from inorganic material, i.e. via the sun and elements on the Earth. This had allowed life on Earth to tap into a whole new energy resource, one that was literally inexhaustible - the Sun. Life began to flourish, and the autotrophic organisms had tapped a new niche allowing the biomass of Earth at the time to dramatically increase. The autotrophs en masse were absorbing carbon and light. The light invariably would always be an available source for synthesizing energy, while the carbon was not. CO2 was constantly being absorbed by these organisms, and after the biological reactions responsible for creating energy in them, oxygen would be released as a by-product. This meant that oxygen began to accumulate in the oceans where life existed. This new material would in turn be taken advantage of by the adapting organisms, alias, leading to the creation of aerobic organisms, who used oxygen as a component of their energy creation. This is another example of life diversifying to adapt to its environment and exploit the niches that it could occupy. This type of evolution continued, where the supply of potential energy making elements and compounds outstretched the requirements of life, therefore organisms continued to adapt to fill all available niches as opposed to competing with one another. Pathogens existed by this time, and were able to leech resources from their single cell hosts, kill them, and move on to the next host after multiplying. On top of this, resources for all organisms alive at the time were being stretched by the increasing population of species' and also the diversity of unique species. Alias, the exhaustible materials used by species were limited, and they would have to 'fight for their right' to survive. To do this, natural selection would give them a competitive advantage over other organisms and perhaps relieve stress caused by competition within the species (intraspecific). One noted event in the origins of life is the emergence of protists. Although these organisms were single celled like all other organisms, they were notably bigger, some being visible to the human eye. This adaptation must have been a selective advantage at the time, either over competitors or taking advantage of an ecological niche. In fact, the adaptive change is believed to be anatomical. Unlike other organisms, the protists contained cell organelles, which meant that a fundamental difference in the way life operated had arisen in the case of the protists. The occurrence of the protists was so unique that the diversity of them substantiates the Animalia and Plantae classifications, because differentiating characteristics were noted, i.e. the presence of organelles. Basically, protists are unique because they possess a nucleus which contains the genetic information of the cell and alias the organism. Previous species were more simple in their nature, and did not possess such a complex cellular structure. The mitochondria is present in both animal and plant cells in today's world, suggesting that the arrival of the mitochondria in the evolutionary chain was slightly before recognizable taxonomical differences between animals and plants. The mitochondria is unique in the sense that the organelle contains its own DNA, which is derived from its parents. Naturally, as the mitochondria is responsible for the breakdown of organic molecules to release energy (i.e. respiration), this DNA was responsible for the reactions involved to do this. The remarkable thing about mitochondria is their striking similarity to that of a species of amoeba, where the structure of the two are similar. In this particular species of amoeba, symbiotic bacteria enact what the mitochondria does in more advanced cell structures. The end of this symbiotic relationship no doubt increased parasitism, due to the fact that cells now possessed their own energy supply, they could be exposed and eradicated by the pathogens of the time. Although geological records for this period are sketchy to say the least, evidence suggests that organelles continued to diversify in this period, further differentiating the taxon that we use today to class them. Hair like structures called cilia and flagella were developing in some species, allowing them to move with wind and water currents. This general progression and diversification has lead to the range of functions that cell organelles perform in modern organisms. The most unusual thing about natural is its repetition of a particular characteristic across a broad band of species. Such a situation arises when looking the development of unicellular organisms at the time. The organelles developing within these species all have structural similarities in relation to function. As in the example above, the mitochondria on a single cell is very similar to that of an entire species, yet mitochondria are found in almost all forms of organisms that have existed on Earth. A push-pull relationship is notable in the evolution of these organisms. In one instance, they become more similar, either because the similarity is an advantage or because environmental pressure was forcing natural selection and thus the species to evolve in this way. On the other hand, organisms were diversifying to occupy previously sterile environments, therefore adapting to better suit their new environment. On the other hand of this, other organisms (as above) would adapt closer to them, due to less competition in the habitat and natural selection favoring a move to this environment. In other words, nature at the time, both parasites and uni-cellular organisms, were more in less in equilibrium, continuing to expand but also moving away/moving closer in relation to other organisms...life continued to change into the Cambrian Period, over half a billion yearresented conditions unbearable to the species and the technology of the time. However, more complex tools were being developed, and that has continued over the period of time where we have successfully monitored historical events in our human race. At this point, human history in the abstract manner truly begins.
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