There are many different life forms on earth. New species and different sub species are evolving every second as others die out. In order to explain the origin of life, people have used the bible story of creation, while others came up with their own theories.
Out of all those theories, the theory of evolution by Charles Darwin seems to have the most supporting evidence to back it up. Evidence on earth suggests that single cell creatures are the ancestors of all life.
These organisms slowly evolved into air breathing creatures when oxygen was created. Slowly, the as land dried up, these creatures moved away from the water and on to land where they evolved legs and a strong back bone.
The theory of evolution by Charles Darwin explained how life evolved from survival of the fittest, it provides a logical explanation of the evolutionary process these creatures took, and how human came to be. Evidence on earth shows that single cell organisms eventually evolved to multicelled organisms and complex beings.
If you look at old fossil records, the oldest fossils are all single cell creatures. These simple creatures do not require oxygen to live.
It took in energy from the sun and other energy sources. Slowly as oxygen begins to appear on Earth, some of the organisms began to evolve lungs to breathe oxygen because “When free oxygen entered the picture. Breathing is more efficient than drawing energy from the fermentation process that earlier microscope life used.” (Science: Biology Pg.
36) Other organisms that did not evolve lungs either died out or went down to deeper depths of the ocean; “Oxygen was first consider a pollutant by microscopic creatures.” (Evolution Pg. 36) Because of the free Oxygen those who did not change were killed. The evolution through natural selection and survival of the fittest shows that Darwin theory is correct.
Due to the lack of oxygen within the ocean , fish slowly evolved to the condition of land. Due to the sudden increase in the population of fish and other marine organism. Due to the sudden increase in the population of marines life, the oxygen level within the ocean decreased. “Scientist believe that the lung fish evolved because of a lack of oxygen in the sea.
The lung fish learned to rise from the sea and breathe in the oxygen necessary for survival.” (Evolution evidence Pg. 38) As more land emerges and dry, rain collected and formed fresh water lakes and rivers. Some of the fish became stranded by the receding ocean.
Many fish that became stranded died because they were not able to adapt to the new environment; “those fish needed salt water to lived died. But some adapted to their environment.” (Evolution Pg. 38) The lobe fin fish was another evolutionary path fish toke to avoid the lack of oxygen in the sea.
“Fossil record shows that lobe finned lung fish took another evolutionary path.” (Microsoft Encarta Pg. 2) The lobe fin fish was almost capable of leaving the water. It only needed more muscles in the joints to be able to lift it self up, because of this many people believe that the lobe fin fish was the ancestor of early reptilian creatures.
The different evolutionary paths the fish have taken shows that life changes in responses to different environmental conditions. Fossil records in South America, reveals that there are many sub species of the human race. The fossil of Neanderthal man was discover shortly after Darwin published his book on evolution..
The Neanderthal man was consider to be an ancestor of mankind because of the size of the skull which suggested that it had a small brain. The sloping forehead is also an indication that it is a ancestor of the human race. Not long after the discovery of the Neanderthal was found in the 1890’s. This fossil was called the “Java Man”, the Java Man was not consider “the missing link between humans and apes.
” (Evolution Pg. 102) The Java Man was too alike a normal human to be the missing link. The missing link is a fossil of a creature that is in a transitional state between it original form and it new form.(I.
e. A dinosaurs with feathers) With the discovery of Lucy in South America it was concluded that Human were likely descendent of the Ape family. The unique thing about Lucy was that it skeletal structure was almost complete. “From the bones, scientist can tell that Lucy was about three and a half feet tall and weighted about sixty pounds.
” (Evolution evidence Pg. 48) Lucy looked like a human from a far but up close, Lucy still had the appearance of an ape. With the discovery of many different fossil of the “Homo” family, it certain that human did evolve from an ape like creature. In the creation story it said that God created everything in 7 days.
It can’t be used literally but still does not provides enough information about creation to explain everything. The creation story can explain how the first creatures was formed but that is about the only logical thing in the story. The existence of God is debatable and thus the creation story does not have any solid proof to be a valid theory. The creation story also says everything was created in 7 days but evidence shows that the earth is ever changing.
There are many contradiction between the Creation story and the Earth. For example. We know for a fact that life on earth changes overtime in response to the ever changing environment. The creation story could be used to help further develop Darwin theory of evolution.
The creation story does not explained how life evolved from survival of the fittest, it does not provides a logical explanation of the evolutionary process these creatures took, and what happen before life existed. Evolution can’t explain certain aspect of how life came to be. There are many scientists that disagree with Darwin views on evolutions. The reasons that scientists disagree is because “they think the fossil record shows that there were ‘jumps’ in evolution that Darwin’s idea does not explain”.
(Science: Biology Pg. 167) The jumps does not occur often but is still there. The fossil record was consider inaccurate by some scientist since it shows the natural selection side of the story. The other scientist say that “the major changes, macro evolution, that bring about new species come in ‘jumps'”.
(Evolution & Creation Pg. 148) The jumps theory does not have enough evidence to be widely accepted, however is still consider one of the major theory in how life become so diverse on earth. Creation and intervention are all non valid theories of how life came to be on earth. Evolution is the only theory that have major evidences to back it up.
The question of which theories is correct is base upon opinions of others. Evolution no doubt did occur and that is the reason why there are so much diversity of life on earth. Human and other modern day creatures all show characteristics of creatures in the past. The main reason people reject evolution is because they don’t believe they could be related to a more primitive creatures because they are consider inferior.
The theory of evolution is the best theory for life on earth and unless more evidences suggest other wises, it will most likely be a fact instead of a theory.
Cite this Different Life Forms on Earth
Different Life Forms on Earth. (2018, Jul 15). Retrieved from https://graduateway.com/different-life-forms-on-earth/