The process through which populations of living creatures adapt and change is known as natural selection. Favorable features are passed down across generations as a result of this natural selection process. Natural selection can result in speciation, which occurs when one species gives rise to a new and separate species.
Natural selection works by comparing individuals within a population that have different traits or behaviors. The individual with the difference or trait that gets passed on to future generations most often will survive and reproduce. The individual without the difference or trait will not be chosen by evolution and will not live long enough to reproduce.
There are three main ways that natural selection can cause organisms to evolve into new species: selective survival of favorable traits, random extinction of less fit organisms, and divergence between populations due to geographic isolation or environmental differences.
Selective survival of favorable traits means that individuals within a population that are able to possess certain characteristics more effectively will have better chances of surviving and reproducing. These characteristics could be physical (such as armor plating for protection) or behavioral (such as fleeing from danger). Individuals with these characteristics will pass them on to more offspring than those without them. Over time, this will result in a population full of people or animals that all share the same characteristic. Selective factors can be based on physical appearance, such as skin color, or behavior, such as fear of spiders.
Natural selection is an evolutionary mechanism. Organisms that are more suited to their surroundings are more likely to survive and pass on the genes that helped them succeed. Species change and diverge as a result of this process over time. It affects both genetic and physical traits.
Within a single population, natural selection acts on the individuals that are best adapted to their environment. This results in those individuals having greater chances of passing on their genes for survival to future generations. The organisms with the least amount of genetic variation tend to be affected first by natural selection because they are not able to adapt quickly enough to changes in their environment. Groups of organisms that live in different environments may also experience natural selection. For example, if one species is able to eat plants that another cannot then these plants will not be eaten and will therefore not be passed on. Natural selection can also act between species. If a predator evolves which is better at catching prey than its counterparts then this will give the prey no advantage and so will reduce the number of predators in the ecosystem. Natural selection is responsible for the evolution of traits such as agility, aggression, coloration, and camouflage among others.
There are two types of natural selection: biological and cultural. Biological selection occurs when individuals vary genetically in their ability to survive and reproduce. This means that some individuals are more fit than others and so they have a greater chance of passing on their genes to future generations.
These beneficial features grow increasingly widespread in the population over time. This phenomenon occurs when there are insufficient interbreeding events between two different populations so that they cannot exchange genes with each other. As a result, they evolve into two unique species.
Natural selection is the main force behind evolution. It selects for or against traits depending on whether they help or hurt an organism's chances of survival and reproduction. The term "natural" here does not mean "without human intervention," but rather that these changes occur within a species as it evolves over many generations. The environment plays a role in determining what traits are favored by natural selection - those that help an organism survive and reproduce better will be selected over those that do not. But environmental factors can't create new genetic information - only natural selection can do that.
For example, assume that you live in a world where food is scarce during certain periods of the year. Your ancestors who were able to hunt and gather food regularly would have an advantage over others who could not. Over time, these traits would be selected for by natural selection. Eventually, people would stop hunting and gathering and become farmers instead. Only those individuals with the necessary genetics for agriculture would survive.