Author at The Secrets of the Universe, I am a Biology and Chemistry high school student from Poland. I love writing about conquest and research in space and future possibilities for Humanity and Astrophysics.
In the previous articles from the series we discussed the main aspects of the theory of evolution. Using that knowledge we can follow major outcomes of evolution and create a series of conclusions.
Evolution is an ongoing process
Since its beginning, life adapted to viral changes, evolving to forms we know today. Without any of the five mass extinction events, Cambrian explosion, or even minor changes we did not discover yet, we would not be here today. However, that does not mean evolution process is over. Human race, and every other existing species, changes gradually and those changes will not be observable in years. Moreover, some of the effects of homo sapiens adaptation can be seen today. We know that during the nineteenth century the average height of a man was about 1.67 m (5’4 feet), five hundred years later it is 1.7 m (5’9 feet).
Outcomes of natural selection
Natural selection favors development of similar traits in similar environment. On the other hand, some features will show common ancestry between different species. In the first case, some species have organs that have different built, however they have the same function. We call those analogical organs, they point that organisms are not related, but evolved in similar environment. Their opposite- homologous organs- have similar built, but different functions. They indicate, that organisms have common ancestors, but they adapted to different habitats. Moreover, natural selection leads to other predictable outcomes. Adaptive radiation occurs when a single species evolves into a number of different, but similar ones. Each of them fills different ecological niche, this process usually occurs when new, unused resources occur.
Three patterns and variation
We can mark out three different evolutionary patterns of organisms. Firstly, there are specialists- organisms that perform best in different environments. Secondly, phenotypically plastic species match the most fit trait value for each set of environmental conditions. In contrast, generalists converge one phenotypical intermediate, and can survive in all kinds of habitats. Moreover, different kinds of variation influence all evolutionary mechanisms. Variation within each species make various possibilities for adaptation. Mutations catalyses variation and creates ground-breaking survival strategies. Trade-off and genetic drift also increase variation and are ultimate source of constant changes within species. Variation is both one of the outcomes of evolution and its totalizator.
The Hardy-Weinberg principle states that allele frequency will remain constant without the presence of evolutionary influences. That means, population would not change from generation to generation. This principle assumes that organisms are diploid, only sexual reproduction occurs, generations are non-overlapping, mating is random, population size is infinitely large and allele frequencies are equal in the sexes. However, when some of those assumptions are unfulfilled, populations change, depending on which factors are different. The Hardy-Weinberg equation is used either if a population fulfills proportions (the genotype frequencies can be calculated), or if the genotype frequencies are known (they can be tested for deviations).
What is next?- further evolution
Scientists keep on trying to predict how humans may evolve within years. Species try to adapt to climate and habitat change, catalysed by humans, though it is too rapid for them, and causes more extinctions every year. All evolutionary mechanisms keep on going, and no one really knows where they will lead human race. There are predictions, that we may be able to develop genes that will help us adapt to increase in lifetime.
I hope in this article you learned about the main outcomes of evolution, and its importance. We will conclude the series by going through the history of study of evolution. If you enjoyed the article, please share it with family and friends. For further studies check the links, contact me if you have any questions.