Adaptation – Theory, Causes, Types and Examples

Process of Evolution – Adaptation

Introduction:

According to evolutionary theory, adaptation is the biological process through which organisms adjust to new surroundings or changes in their current environment. Although scientists had examined adaptation before the 1800s, it was not until Charles Darwin and Alfred Russel Wallace developed the concept of natural selection.

Wallace felt that organisms’ evolution was linked in some manner to their adaptability to changing environmental circumstances. Wallace and Darwin both went beyond adaptation to construct the concept of evolution by natural selection, which describes how organisms adapt and evolve.

According to natural selection, traits that are passed down help animals adapt to their circumstances better than other creatures of the same species. When compared to other members of the species, this allows for higher survival and reproduction, leading to evolution.

Organisms can adapt to their environment in a number of ways. They have the ability to adapt physiologically, which means they can modify the way their bodies function. The bodies of people who live at high altitudes, such as in Tibet, are an example of biological adaptation.

Tibetans live at altitudes where oxygen levels are up to 40% lower than at sea level. Most people would fall unwell if they breathed such thin air, but Tibetans’ bodies have changed their chemistry. Most humans can survive at high elevations for a short length of time because their bodies create extra hemoglobin, a protein that transports oxygen in the blood.

However, because sustained high amounts of hemoglobin are harmful, increasing hemoglobin levels are not a long-term answer to high-altitude survival. Tibetans appeared to have evolved genetic alterations that allow them to utilize oxygen more efficiently without the need for more hemoglobin.

Behavioral adaptation may occur in organisms as well. In the depths of winter, emperor penguins in Antarctica congregate to exchange warmth. Prior to the creation of evolutionary theory, scientists such as Georges Louis Leclerc Comte de Buffon researched adaptation.

He was a French mathematician who thought that organisms evolved through time by adapting to their geographical settings. Jean Baptiste Lamarck, another French scholar, believed that animals might adapt and pass on their adaptations to their young and, therefore, develop.

Natural selection is the process through which adaptation occurs. Natural selection happens when organisms in a population differ in some manner. Some may sprint faster in order to catch prey. Others may be equipped with camouflage to assist them in avoiding being eaten.

Individuals with beneficial qualities tend to live longer lives in any group. They are more likely to breed and pass on their beneficial characteristics. Beneficial qualities spread across the population over many generations. Less helpful characteristics become less prevalent. Some even vanish. Long-term change is referred to as evolution.

Examples of Adaptation

• There are several types of adaptations. Some are physical characteristics. Others are actions. Polar bears, for example, have thick fur coats to keep them warm. Meanwhile, penguins gather together for warmth.
• Plants, too, have adaptations. Take, for example, cactus; these plants have stems that can hold water for an extended period of time. This aids them in survival in the desert. Humans, too, have adaptations. Consider the people who dwell on Asia’s Tibetan Plateau. That area is situated at a relatively high height.
• The oxygen content of the air at that altitude is low. People who live there, on the other hand, frequently have genes that let their bodies use oxygen quite efficiently. This enables them to thrive in an environment where others would perish.

Adaptation Theory

Adaptation theory, commonly known as the principle of survival of the fittest, refers to an organism’s capacity to adapt to its surroundings and adjust through time. Charles Darwin developed his idea while conducting research on Galapagos Island in the 1830s.

Many earlier scientists, like Empedocles, Aristotle, William Paley, Lamarck, and Buffon, acknowledged the fact that species change through time but did not grasp the fundamental reason for this change or that adaptation was a continuous process with no ultimate form.

According to adaptation theory, as the environment changes, three further changes occur: habitat tracking, genetic change, and extinction.

• Habitat tracking: When an organism that used to reside in an environment discovers another habitat that is similar to the one it previously inhabited.
• Extinction: It occurs when a species is unable to adapt to a new habitat or migrate out and find a new environment to exist in, and hence dies out and becomes extinct.
• Genetic change: Genetic change is a type of natural selection that permits animals with minor changes to outlive other species in a given environment.

Causes Of Adaptation

Adaptation may arise as a result of mutation or natural selection. Mutation is an abrupt genetic alteration that can be either inadvertent or random. Any alteration in the nucleotide sequence of DNA, as well as the replacement of a single pair of nucleotides, will result in mutation.

Certain mutations are harmful to humans, while others may be beneficial to an organism’s survival in the battle for survival. For example, a bird is born with a large beak, which aids in food capture and hence, survival. As a result, this bird can live and reproduce more effectively. This gene is handed over from one generation to the next.

Types Of Adaptation

Structural Adaptations:

These are the physical characteristics of an organism that aid in its survival in the environment, including the many types of terrestrial habitats. Physical changes are linked to changes in the physical environment. Consider camouflage, which is a protective coloring that allows an organism to blend in with its surroundings. This keeps predators at bay and boosts their chances of survival.

Behavioral Adaptations:

Behavioral adaptation is the modification of an organism’s behavior in order for it to survive in a certain environment. Behavioral adaptations are difficult to discover, and it often takes thorough field and laboratory investigations to bring them to light. Migration is an example of how a bird migrates to the south in the winter because there is more food available, but some birds also migrate for the purpose of reproduction.

Physiological Adaptations:

Physiological adaptations are bodily processes that aid an organism’s survival and reproduction in a given environment. These adaptations might be the many ways in which an organism responds to environmental stimuli. These changes are mainly dependent on body chemistry and metabolism and hence, are not visible from the outside. To trace these sorts of adaptations, laboratory investigations that analyze the amounts of various bodily fluids are frequently required.

Co-adaptation:

Co-adaptation occurs when two or more species are symbiotically tied to each other for survival and adapt together.

Importance Of Adaptation

Adaptation is required for living species to survive. Animals that are unable to adjust to changing environmental conditions perish. Genetic alterations have resulted in these adaptations. The surviving animals pass on the altered genes to their progeny. This is referred to as natural selection.

Camouflage and coloration are adaptations that protect them from predators. DNA mutations aid in the survival of animals in perilous situations and these survival features are handed down to future generations. These adaptations allow a wide range of organisms to live on the planet.

Charles Darwin examined turtles from two different islands. The turtles on one island had small legs and straight shells and ate food that was low to the ground. A few turtles relocated to another island, where the food was considerably more plentiful. Longer-legged turtles survived. Over time, their necks grew longer and their shells rounder. As a result of these modifications in their species, the population on the new island expanded.