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Natural Selection Definition Biology

What is natural selection definition biology? In simple terms, Natural selection is the selective adaptation of organisms to a environmental setting that is favored by the organisms. Natural selection is a gradual process that results in the survival and reproduction of organisms according to differences in environment. It is an essential mechanism of evolution, whereby the difference in the adaptive traits characteristic of an individual over multiple generations results in the subsequent evolution of an entirely unique species.

Natural Selection Definition Biology is the difference between survival and reproduction in humans due to genetic differences. It’s a critical mechanism of nature, the gradual difference in the heritable qualities of an individual over time. Over many thousands of years, natural selection has shaped the characteristics of human into what they are today. There are many examples of natural selection in action in humans. The spread of agriculture around the world, and the different religious groups over time reflects the work of natural selection.

Natural Selection

Natural selection theory

Natural selection, also called Natural Selection Theory, is the idea that evolution can be controlled and even consciously managed.

Natural section theory was proposed by

Natural section theory was proposed by Charles Darwin in 19th century.

Natural Selection theory of Darwin states that

Darwin’s premise of natural selection in biology is that the characters of an organism can be passed on from one generation to the next by the actions of the surviving members of a species. Natural selection can be either gradual, or gene-driven. Gradual natural selection occurs through gradual changes in the environment over time, such as the accumulation of body fat in some species over time that allows them to become larger than other life forms. Gene-driven natural selection, by contrast, occurs when a favorable gene is passed on from one member of a species to its offspring. Over time, the advantageous genes may outcompete other genes, resulting in a drastic reduction in the fitness of the organism.

Natural selection can also be explained by population genetics. Population genetics studies the population characteristics of a species and tries to fit them with the genetic makeup of an individual. The population genetics of humans and other animals have been analyzed closely over the past decades. A number of theories have been formulated to explain the population genetics of various species.

1. Survival of the Fittest

One of the most popular population genetic theories postulates that the success of any kind of population is determined by natural selection. It is said that a small number of individuals will dominate a given environment and that these individuals will have the strongest traits that will lead to their successful reproduction and survival. It is also believed that natural selection is responsible for the variations in languages and culture across the world. Different populations may be able to co-exist because of the existence of natural selection.

2. Selection

Another theory of natural selection has the idea that a trait that provides a benefit to a population will be selected over another trait that does not provide the same benefit. The benefit could be in the form of improved fertility or strength. In cases where a number of individuals have the ability to produce more children than others, natural selection will select those individuals who can reproduce. Those who do not reproduce will be replaced by their younger siblings.

3. Variation

The third theory of selection states that a character trait that is favored in one environment may become less favored in another environment. For instance, the color of a leaf may be preferred in some environments, but it would be less favored in another. This could explain why there are some brightly colored birds that are rare in some environments. The variation of selection could also be caused by different amounts of gene flow among members of a population. If a population has members who breed together often, the number of members that mate with each other will be higher than the number of mates if they did not have such relationships. This could explain why some populations have a high number of violent individuals.

There are several theories of natural selection that have been studied for years. Each one is based upon the process that selection goes through during the evolution of a species. No one theory exactly explains the process perfectly, but they all do agree on the general concept that natural selection is a mechanism that drives a population towards survival and fecundity. It can be used to explain many of the differences we see among people and among species.

Natural selection theory Examples

1. Adaptation of brown beetles to avoid predators

An example of natural selection in biology is the adaptation of brown beetles to avoid predators. Through natural selection, a variety of brown beetles have developed a chemical alarm that will mark their territory and signal the fellow brown beetles that they are no longer safe for the colony. This chemical alarm, called Xerces Blue, serves as a defense against the more deadly lacewings.

2. Convergent Evolution

Another example of natural selection is that of sexual reproduction. Through the accumulation of more males during reproduction, an organism can increase its chances of survival when compared to its potential competitors. This is an example of convergent evolution.

3. Gradient of traits

Natural selection can also occur along a gradient of traits. The different traits that are considered ‘positive’ or ‘negative’ are those that decrease the survival of an organism or increase the fitness of an organism. Two examples of traits that can be considered ‘negative’ traits include traits that directly effect reproduction, such as the absence of a mate, or traits that have a fitness component but do not directly effect reproduction. In this case, traits that are directly related to the fitness of an organism can be considered ‘positive’ or ‘neutral’.

Examples of positive traits include beneficial mutations that enhance the fitness of an organism.

In nature, natural selection definition biology favors traits that are beneficial to an organism’s survival. The most well-known example of this phenomenon is the tendency of birds to lay eggs in their nest rather than gathering food from nearby flowers. This reproductive strategy is favored by natural selection because it increases the chances of the eggs being fertilized with sperm from the nearest body of water. However, when this strategy is practiced over again by different species of birds, this becomes a problem because the local species become extinct. In order to prevent this from happening, the mutations that confer this advantage to local species must be removed by means of natural selection.

4. Evolution of higher forms of life

Natural selection is also used in the evolution of higher forms of life. An example of this comes from the way that eyes evolve into more complex forms. As an animal or insect becomes more mobile, its eyes adapt by becoming larger and more specialized. In order to allow for increased variation in eyes, natural selection will sometimes select for an eye to be large and round, while another eye becomes smaller and more spherical. In cases such as this, a mutation that favors the larger eye has been favored through natural selection. Since this eye is the best suited to an organism’s lifestyle, it will typically be passed on to future generations.

5. Cancer in Humans

Another example in modern human life is cancer. Some cancers are very difficult to treat and even kill. Some have evolved over the course of thousands of years to become more resilient to treatment. Resistance to treatment is what makes some cancer cells better than others, so when natural selection created these cancer cells, it favored those with better abilities to resist the treatment. These same cells also tend to survive better in a variety of other environments.

6. In Insects

Another good example of natural selection in action is in insects. Insects reproduce asexually, and in pairs, reproduce only one time. If the husband and wife reproduce together, both take care of their offspring, and so on and so forth. As an example, certain species of brown beetles have evolved to live together in large groups.

Human life is composed of organisms that live in diverse environments. Each environment offers a selection of organisms to select from that will thrive and reproduce. One of the forces behind natural selection is predator-prey selection. A predator like a wolf, a big fish or other large marine organism will eat the organisms that are less abundant and rarer to reproduce. The less-represented the organism is, the weaker it will be.

Now, the question is how does it apply to human life? Well, consider what we know about the history of mankind. People are willing to fight and die for their ancestors’ livelihoods, and in many cases, their own lives. Those who possess a survival gene that increases their ability to reproduce have a leg up in society, and can come out ahead in reproductive success.