@ embryology and molecular evidence
Genetics is one of the key aspects of evolution, and evolution is an ongoing process. The entire theory is supported with adequate genetic evidence to evolution. It is believed that we have descended from a common ancestor which had one set of the genome. Mutations of these genes led to the formation of newer and different species from that single genome.
A combination of the accumulation of these mutations and migration to different areas for suitable habitation led to diversity. Some even became extinct on the way while few others took to newer habitats. Genetic variants emerge as a result of a mutation which will be scattered and maintained in the populations because of two key concepts – natural selection and genetic drift. Molecular evolution is driven by three factors, which are:
- Selection
- Mutation
- Recombination – Genetic drift and Gene conversion
Concepts Supporting The Theory Of Evolution
Listed below are a few concepts that promote the evolution theory:
- Molecular Evidence: An alteration in the sequence composition of molecules of the cells such as RNA, DNA and proteins over generations is referred to as molecular evolution. It is based on the laws of population genetics and evolutionary biology in order to illustrate changes in the pattern. All species possess the four carbon-based molecules which are – nucleic acids, amino acids, carbs, lipids and the RNA, DNA molecules.
- Natural Selection: It is one of the main concepts that brings about evolution. It is a process wherein entities better survived to their surroundings, tend to survive in spite of the environmental pressures. These entities will mate to reproduce hence passing on their genes which gradually turns out to be the most common characteristic exhibited in the generations.
- Sexual Selection: It is a natural selection process which arises through preference by one gender which looks for certain traits in an individual from the opposite gender. These species look for their mates with a specific trait which usually indicates towards possessing good genetics.
- Artificial Selection: Manual selection of desired traits in a particular animal takes place. These animals with selected traits that are exhibited are made to breed with animals exhibiting a different genotype altogether, in order to produce a unique species.
- Anatomical Compositions: Many animals possess similar body structures that aid them in performing different functions. These structures are known as homologous structures. Analogous structures, on the other hand, are different structures that exhibit similar functions. This is dependant on the environments. Similar environments help in coping with the same problems.
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Embryology: Embryos look very similar to each other, we have all derived from embryos. Hence homologous structures can serve as evidence for common ancestry while similar adaptations can be exhibited be analogous structures. The relatedness of species and biogeographical patterns can be determined by the differences and similarities in biological molecules. The existence of different types of species in various eras can be known through examination of the fossil.
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