Concepts of Evolutionary Biology

The gradual change in the genes and physical appearance of species due to various factors is biological evolution, meaning that the world’s organisms are in constant flux. The study of these processes and changes comes under evolutionary biology. This sub-area of biology studies various evolutionary processes such as natural selection, speciation, descent, etc., and tries to determine the future trends and changes that may take place by connecting the extant forms of evolution to their causes. 

History

Evolutionary biology emerged as a discipline in its suitable years after the theory of evolution was proposed by Charles Darwin in 1859. In the 1930s and the 1940s, evolutionary biology became an academic stream in modern synthesis. But it was by the 1980s many universities in the US had created departments of evolutionary biology. Many life sciences disciplines are making way for evolutionary biology as part of their syllabi. For example, microbiology is becoming more bent towards evolutionary studies because of the latest finds in microbe genomics and physiology.

Sub-disciplines

Biology can be divided based on various criteria. The traditional way of differentiating the biological disciplines was to divide the areas of study based on the taxonomic divisions, hence the subjects of botany, zoology, and microbiology. Another way was to work with the molecular and cellular organisation to the populations of organisms in biological organisation. Yet another way is by delineating the study methods such as field biology, theoretical biology, experimental biology, and palaeontology. These ways of organising the various disciplines in biology can be merged with evolutionary biology to form further areas like evolutionary developmental biology and evolutionary ecology. 

With recent developments in biology and applied sciences, new fields in evolutionary biology have come up. Some of these fields are:

• Evolutionary robotics
• Bioengineering
• Bio-algorithms or evolutionary algorithms
• Bionomics 

The basic underlying principles of evolution are used to solve modern-day problems and come up with solutions that are conducive to the welfare of people in ways that are sustainable for the planet.

Biological evolution: meaning and types

• Meaning: Evolution is the gradual change in heritable traits over time caused due to changes in various habits or habitats. These changes happen over several generations. The changes occur due to the changes in genes passed down from one generation to the next in the populations of species. Differences in characteristics exist among the members of the same population. Evolution occurs when these characteristics are chosen over other traits due to evolutionary processes such as genetic recombination, genetic variation, natural selection. Some characteristics become more common or rarer based on the population’s needs due to these evolutionary processes 

Types: The types of evolution are as follows:

• Adaptive evolution: The changes that make an organism adapt to its environment are adaptive evolutionary changes. These happen because of changes in the environment. As with other evolutionary changes, these changes give the organisms the best chances to survive and reproduce
• Convergent evolution: The development of similar features or traits with similar functions in organisms that are not of the same period is known as convergent evolution. However, these analogous structures were not present in the last common ancestor of these species
• Coevolution: When two or more species cause evolutionary changes in each other, it is known as co-evolution. Organisms often form symbiotic relationships with each other as a result of coevolution. However, the most common type of coevolution is the predator-prey co-evolution. The predator evolves traits that help it be better at catching its prey. And the prey must develop features that allow it to evade capture. Another common type of coevolution is the one found between pollinating insects and plants dependent on pollination

Biological evolution and its processes

Evolutionary biology studies the various processes that cause evolution. This helps in understanding the purpose of the characteristics of the organisms. These evolutionary processes are as follows:

• Genetic drift: These are genes that result from a random event that influences the frequency with which a particular gene occurs in a population. So genetic drift is a function of chance in genetic mutation. Genetic drift can cause specific previously rare genes to become more frequent in their occurrence in DNA. It can also make hitherto common genes lose their frequency of occurrence
• Gene flow: The transfer of genetic material from one population to another population of the same species is known as gene flow. If the rate of gene flow is high, then the frequency of shared genes between the two populations will rise till the two populations effectively become one population

• Mutation: The changes that happen in an organism’s genome are known as mutations. These happen in the nucleotide sequence of the genome and result from erroneous replication of DNA or errors in the repair of any DNA sequence that has suffered some damage

• Natural selection: The selective reproduction or survival of certain members of the population due to variation in the phenotype or their observable characteristics is known as natural selection. This results from the superiority of variations that exist in all populations. Some variations provide better chances of survival to members of the population who possess them, and these get passed down to their offspring

Evolutionary developmental biology

This field of evolutionary biology studies how developmental changes in species occur by comparing the different processes in different organisms. With the help of recombinant DNA technology, it has become easier to understand the process of development. The insights achieved through this study helps in understanding the current body plan of various organisms and give more profound knowledge of the multiple functions of the body parts of organisms.

Conclusion

Today evolutionary biology combines various disciplines from molecular genetics to even computer science. This creates a lot of scope for study. The challenges faced by the field include the mathematical computations required for integrating DNA sequences into evolutionary theory. This needs to be done for a better understanding of genetic