Evolutionary Biology

As the various species of the world evolve and adapt to their environments, there are variations in their traits, characteristics, behavioural patterns, and personalities. The species adjust themselves to fit within the changes while suitably adapting themselves for survival. The ecological habitats are the place of their survival, and these habitats promote the growth of evolution through different stages of development. Changes in how we live and adapt to our ecosystems are inherited from our ancestors. This article delves further into the topic and provides a detailed understanding. 

Evolution is a continuous process during which certain characteristics become either common or rare in the members of a particular species over time. These changes are passed, bringing significant variations in the forthcoming generations. This phenomenon is called evolution.

The variations in the traits and characteristics of species (individuals and organisms) over several generations depend upon the development of natural selection. The theory of evolutionary biology is based on the knowledge that all species continue to progressively change over time. 

Biological evolution meaning

The definitive study of evolutionary biology takes place in two ways. These are as follows:

1. Paleontological records show the changes in plants and animals deposited on sedimentary rocks over various ages. Different forms of life give rise to several other species. To understand this better, it is important to know that terrestrial plants and animals are from aquatic life forms; all reptiles such as snakes, lizards, turtles, and dinosaurs are from amphibians; and all flora and flowering plants are from ferns. The extinction of dinosaurs led to the spread of mammals in the ecosystem, and this continues. 

1. Genetic changes transferred from the ancestors can be accumulated in a species, and the consequences can be the replacement of the gene variants augmented by statistical genetics. This is called microevolution. Under microevolution, the species adjust as per the changes in their environments and improve their functions accordingly. 

The complexity in the organisms increases, and the reproducible sequence among the species helps to achieve the evolutionary process.

Evolutionary Process

According to extensive research and estimations that have taken place, the ecosystem is home to around 8.7 million living species. This number continues to increase as the changes progress. These are numerous species of living organisms that are still unknown. Microorganisms can be classified into different groups based on various criteria, and species are arranged in a hierarchical sequence of groups by biological classification.  

There are several criteria to be considered while arranging species into categories. Every biological classification is based on the fundamental design, characteristic features, resemblances, and differences among the species. 

There was a misconception in the 18th century that all organisms on the earth came into being unpredictable. It was later understood and accepted that evolution has caused these changes. This was a result of the introduction of the modern taxonomy system by Carolus Linnaeus. The teachings from this changed our thoughts and views about the concept of evolution.

According to evolution, the current life forms are better versions of the early life forms. The living species that existed several years ago have undergone multiple changes, and new life forms have been ascended from them that have learned to adapt to the changes for a better living.

From classifying the organisms, we can understand that few species have retained their ancestral body designs and features. The changes are not complete, and the process of evolution is prolonged. Several species have developed new and advanced bodies and parts from their ancestors. The current set of species are called advanced organisms, and the ancestral or earlier group of species are called primitive organisms. The primitive organisms had simple body designs, while the advanced organisms have developed complex body designs. Hence, evolution has caused and resulted in the existence of complex young organisms from the simpler older organisms.

Levels in  evolutionary biology 

• The first level of evolutionary biology classification asks: Does the cell have a nucleus or not?  Except for the kingdom of bacteria, all other species have a true and well-developed nucleus.

• The second level of evolutionary biology classification asks: Are the nucleated organisms unicellular or multicellular? The ability to perform photosynthesis is present among multicellular organisms.

• The third level of evolutionary biology classification asks: Is the vertebral column for the species not performing photosynthesis in the body? 

The species’ physiological, biochemical, anatomical, or evolutionary relationships form the base of categorising under different levels.

Conclusion 

Life appeared on earth millions of years ago in water and was simple. The organisms which are found now on our planet are quite different in comparison to ancient life forms. Scientific studies have revealed that certain similarities are there among the living organisms as well as with their fossils. This strengthens the idea of evolution.