Free 740 words essay on Theory Of Evolution for school and college students.
It’s been known for a fact that we, humans, evolved from apelike ancestors. This was an extremely prolonged process and the alterations took place over an epoch of approximately six million years. Over such a long period, our apelike ancestors developed rich behavioral, physical and biological traits depending upon the prerequisite for their surroundings. But it’s not just humans who evolved, each and every one of the living species on earth adapted as per their necessity and generations over generations, these changes formulated an entirely new breed. Many scientists have expressed their views on these adaptations of living beings, but only a few theories were convincing. One of these theories was Charles Darwin’s ‘Theory of Evolution‘. Charles Darwin, a Naturalist, wasn’t really an expert in genetics and mutations, but still his hypothesis contributed a symbolic deal to the modern understanding of Evolution. ‘Theory of Evolution’ was discussed in detail in Darwin’s book, ‘Origin of Species‘. Here are some key features of the theory –
• Every group of living being descended from a single generic ancestor.
• Evolutionary distortions occurred progressively as per the demand.
• The offsprings of the mutated species inherited the parent characteristics.
• Changes occurs in organisms due to ‘Natural Selection‘.
NATURAL SELECTION AND EVOLUTION
Natural selection, a concept which was formulated by Charles Darwin, is the phenomena of acclimation of genes throughout generations in order to survive the atrocities of nature. So the living beings, which are most suited for the environment survives, while the other ones who fails to match the steps with the Nature, meets extinction or rarity. Darwin conjectured that natural selection could induce a ground mammal to turn into a whale. This approximation wasn’t much appreciated by the people. The present scientist states that Darwin’s idea was somewhat right, but the animal he chose to explain was wrong.
Natural selection works on two different levels –
Micro-Evolution is simply a metamorphosis within the same species. The changes occurred are on a small scale and thus can be observed in a small period of time for example, amidst one generation and the subsequent. It can cause a population to change size or color over the span of a few generations. This ultimately gives birth to a whole new variety of descendant within a specific species.
Example – Changes is size of a sparrow over generations according to the atmosphere.
When given enough time to the amassed changes within a species, natural selection can create an solely new species, these transformations are examples of Macroevolution. A single breed splits into two or converts into another breed over a given time interval in macroevolution. It is a long term and large scale process which consists of origin and annihilation of species. Macro-evolution’s event happens due to the processes of microevolution. The two terms are connected and a part of a collective integral.
Example– Humans to ape. ‘Homo-sapiens, evolved from apes and it is one of the best examples of macroevolution.
AN ANOTHER THEORY
Apart from Darwin’s theory “Theory of inheritance of acquired characters”, proposed by a French Naturalist, Jean Baptiste de Lamarck, is also popular. This theory is also known as “Lamarckism“. Lamarck stated that
• With every evolutionary generation, the size of an organism or their component tends to increase
• Organs which are frequently used, develops as per need while the ones which aren’t, results in degeneration.
• New organs are generated as per need.
• Developed characteristics are inheritable and after a given time, results in a species.
Darwin’s theory created a commotion among communities with scientific, religious and political backgrounds. This theory was not based on any kind of genetic study; it was entirely established upon the observations of Darwin. Although years after its constitution, a fortune of evidence from the fossil record and genetics supported the theory. Darwin’s theory was only able to explain the ‘Survival of the fittest’ but it failed to define the use of variations and features in the initial stage of evolution. Some people denounce it because it isn’t able to explain a variety of exceptional cases. ‘Lamarckism‘, on the other hand also faced rejection on some accounts. Eyes & hearts, which are continuously used don’t evolve, but develops defects. Presence of weak muscles in the son of a wrestler was also not explained by Lamarckism.
Evolution is a continuous process and as we are discussing over it, we are also evolving. So this was all about ‘Evolution Theories’. We hope you liked it.