What is evolution?

In biology, evolution is the change in a species' features through multiple generations and is dependent on natural selection.

The theory of evolution is predicated on the notion that all species are interconnected and evolve gradually through time. In order for evolution to occur, there must be genetic diversity within a population that influences the physical traits (phenotype) of an organism.

Some of these traits may confer an advantage over other individuals, which the individual can then pass on to their kids.

Darwin's theory of evolution proposes that evolution occurs through natural selection. The physical traits of individuals within a species vary. This discrepancy is due to variances in their genes.

What is natural selection?

Individuals whose features are optimally adapted to their environment are more likely to locate food, escape predators, and resist disease. These individuals are more likely to procreate and pass on their genes to future generations.

Individuals with low environmental adaptation are less likely to live and reproduce. Therefore, it is less likely that their genes will be passed on to the following generation.

Therefore, the individuals best suited to their environment survive, and, given sufficient time, the species will gradually evolve.

Prior to the industrial revolution in the middle of the eighteenth century, the peppered moth was often a delicate white with black spots. This allowed them to conceal themselves from prospective predators on trees with pale bark, such as birch trees.

The rarer, darker-colored peppered moths were more visible against the pale bark of trees, and were therefore more easily detected by predators.

At the height of the Industrial Revolution, the air in industrial districts became thick with soot. This rendered trees and structures black. As a result, the lighter moths became far more vulnerable to being consumed by birds than the darker ones.

The darker moths were now disguised against the soot-stained trees, making them less susceptible to being consumed. This environmental change caused the darker moths to become more prevalent and the lighter moths to become uncommon over time.

Evolutionary mechanisms work at the genetic level. Changes in DNA sequences influence the structure and expression of our genes, the fundamental units of heredity. To comprehend the evolution of various species, we must examine the DNA sequences in their genomes.

Our evolutionary past is encoded within our genes. The appearance of the human genome is a result of the genetic mutations that occurred in our ancestors. When the DNA and genes of various species appear strikingly similar, this is typically seen as proof that they share ancestors. Humans and the fruit fly, Drosophila melanogaster, share a significant portion of their DNA. 75 percent of human disease-causing genes are also present in fruit flies.

Changes to DNA accumulate over time. Some of these modifications can be advantageous and provide an organism with a selection advantage. Other alterations may be detrimental if they impair an essential, daily function. Consequently, certain genes change little. They are considered preserved.

There are present 3 types of evolution such as  Convergent evolution ,Adaptive radiation and Co-evolution

Convergent evolution When identical adaptations independently arise in response to similar selective pressures. The capacity to fly has separately developed in insects, birds, and bats, for instance.

Co-evolution When two species or groups of species have co-evolved such that one has adapted to the other's alterations. For instance, blossoming plants and pollinators like bees.

Radiative adaptation When a species divides into a multitude of new forms as a result of a change in the environment that creates new resources or environmental problems. Finches on the Galapagos Islands, for instance, have evolved different beak shapes to take advantage of the different types of food available on each island.