What Is Natural Selection In Psychology?

What Is Natural Selection In Psychology
The process by which such forces as competition, disease, and climate tend to eliminate individuals who are less well adapted to a particular environment and favor the survival and reproduction of better adapted individuals, thereby changing the nature of the population over successive generations.

What is an example of natural selection in psychology?

Natural selection is the process by which heritable traits that make it more likely for an organism to survive and successfully reproduce become more common in a population over successive generations. It is a key mechanism of evolution, The natural genetic variation within a population of organisms means that some individuals will survive and reproduce more successfully than others in their current environment,

For example, the peppered moth exists in both light and dark colors in the United Kingdom, but during the industrial revolution many of the trees on which the moths rested became blackened by soot, giving the dark-colored moths an advantage in hiding from predators, This gave dark-colored moths a better chance of surviving to produce dark-colored offspring, and in just a few generations the majority of the moths were dark.

Factors which affect reproductive success are also important, an issue which Charles Darwin developed in his ideas on sexual selection, Natural selection acts on the phenotype, or the observable characteristics of an organism, but the genetic (heritable) basis of any phenotype which gives a reproductive advantage will become more common in a population (see allele frequency ).

  1. Over time, this process can result in adaptations that specialize organisms for particular ecological niches and may eventually result in the emergence of new species,
  2. In other words, natural selection is an important process (though not the only process) by which evolution takes place within a population of organisms.

Natural selection is one of the cornerstones of modern biology, The term was introduced by Darwin in his groundbreaking 1859 book On the Origin of Species, in which natural selection was described by analogy to artificial selection, a process by which animals and plants with traits considered desirable by human breeders are systematically favored for reproduction.

The concept of natural selection was originally developed in the absence of a valid theory of heredity ; at the time of Darwin’s writing, nothing was known of modern genetics. The union of traditional Darwinian evolution with subsequent discoveries in classical and molecular genetics is termed the modern evolutionary synthesis,

Natural selection remains the primary explanation for adaptive evolution,

What is the simplest definition of natural selection?

Natural selection is a mechanism of evolution. Organisms that are more adapted to their environment are more likely to survive and pass on the genes that aided their success. This process causes species to change and diverge over time. Natural selection is one of the ways to account for the millions of species that have lived on Earth. The Museum’s Library holds the world’s largest concentration of Darwin works, with 478 editions of On the Origin of Species in 38 languages. In Darwin and Wallace’s time, most believed that organisms were too complex to have natural origins and must have been designed by a transcendent God. Wallace (L) and Darwin (R) came up with very similar theories on evolution. Darwin has generally overshadowed Wallace’s contributions, however.

What is a good example of natural selection in humans?

Lactose tolerance – In most parts of the world, adults are unable to digest the lactose sugar in milk. One example of recent natural selection in humans involves the ability to tolerate the sugar, lactose, in milk. In most parts of the world, adults are unable to drink milk because their body switches off the intestinal production of lactase, an enzyme that digests the sugar in the milk, after weaning.

  1. As these people cannot digest the lactose sugar they suffer symptoms including bloating, abdominal cramps, flatulence, diarrhoea, nausea, or vomiting.
  2. Yet, more than 70 per cent of European adults can quite happily drink milk.
  3. This is because they carry a regulatory change in the region of DNA that controls the expression of the gene that codes for lactase.

This DNA change enables the lactase gene to be switched on and lactase production to continue, even after weaning. This genetic change appears to have happened between 5,000 and 10,000 years ago, which is around the same time domestication of milk-producing farm animals, such as cows, was established in Europe.

  • This suggests that being able to drink milk into adulthood provided a strong evolutionary advantage in Europe.
  • This may be because sun exposure was much lower in Europe and people were in greater need of the vitamin D found in cow’s milk.
  • Or it may be because cow’s milk provides a much safer and cleaner alternative to drinking water that may cause disease.

Milk may also have prevented death from starvation when crops failed and food was scarce. Those who could not tolerate lactose would die of starvation, while those who could tolerate lactose would survive. Whatever the reason, a strong selection pressure must have favoured those people whose lactase gene remained switched on.

What are some examples of natural selection in human Behaviour?

Natural selection at work – Understanding Evolution Scientists have worked out many examples of natural selection, one of the basic mechanisms of evolution. Natural selection can produce impressive adaptations that help organisms survive and reproduce. A few examples are shown below.

Orchids fool wasps into “mating” with them. Orchid and wasp image courtesy of Colin Bower. Katydids have camouflage to look like leaves. Image © Greg Neise,, GE Neise Digital Communication. Non-venomous king snakes mimic venomous coral snakes. Images courtesy of Neurotoxin.

Blue-footed booby image courtesy of Behavior can also be shaped by natural selection. Behaviors such as birds’ mating rituals, bees’ wiggle dance, and humans’ capacity to learn language have genetic components and are subject to natural selection. The male blue-footed booby, for example, exaggerates his foot movements, an adaptation that helps him attract a mate.

In some cases, we can directly observe natural selection occurring. Very convincing data show that the shape of finches’ beaks on the Galapagos Islands has tracked weather patterns: after droughts, the finch population has deeper, stronger beaks that let them eat tougher seeds. In other cases, human activity has led to environmental changes that have caused populations to evolve through natural selection.

A striking example is that of the peppered moth, which may have either light or dark coloration. During the Industrial Revolution, when air pollution darkened tree trunks, dark-colored forms were favored because they were better camouflaged and so became more common.

What is natural selection in one word?

Definitions of natural selection. a natural process resulting in the evolution of organisms best adapted to the environment. synonyms: selection, survival, survival of the fittest. type of: action, activity, natural action, natural process.

What are the 4 principles of natural selection?

There are four principles at work in evolution— variation, inheritance, selection and time. These are considered the components of the evolutionary mechanism of natural selection.

What is the easiest example of natural selection?

What Is Natural Selection In Psychology Masai giraffe (Giraffa camelopardalis tippelskirchi), four giraffes stand in savannah, Kenya, Masai Mara National Park blickwinkel/F. Stober/Alamy Natural selection is the process by which some organisms in a population survive and reproduce, while others do not, based on their bodies and behaviour.

  • It is one of the processes by which species change from generation to generation, and is a crucial element of the theory of evolution,
  • A classic example of natural selection at work is the origin of giraffes’ long necks.
  • The ancestors of modern giraffes were animals similar to deer or antelope, with necks of ordinary length.
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However, because the trees in their habitat were tall, those giraffes with slightly longer necks had an advantage over their shorter-necked fellows. The longer-necked giraffes reproduced more, so in the next generation longer necks were more common. Over many generations this process produced giraffes as they are today.

  1. This process of natural selection was first described by Charles Darwin in 1859 in On the Origin of Species,
  2. It helps explain how the many varied species on Earth could be descended from a single ancestral species.
  3. Natural selection is sometimes summed up as “survival of the fittest”.
  4. This is true but can be misleading.

The word “fittest” does not necessarily refer to physical fitness. Rather, it means how well-suited an organism is to its environment and lifestyle. The fittest organisms are not necessarily the fastest or strongest: often they are the most cooperative.

Natural selection can produce surprising results, It can produce more complex organisms, for example creating multicellular organisms from single-celled ones, but it can also simplify : for example, fish species that live in dark caves lose their eyes, Furthermore, when circumstances change natural selection can swiftly reverse course,

However, natural selection has its limits. In particular, because it is not guided by a consciousness, it has no foresight and can lead species to evolve down paths that seem advantageous but actually lead to extinction. There is also more to evolution than natural selection,

  • Species can change in a more undirected way by a process called genetic drift, in which certain genetic variants become more common despite not having any particular advantage.
  • When a species is not under strong selection, genes can vary more freely and this sometimes leads to the emergence of remarkable new traits.

There is also sexual selection, in which animals choose their potential mates not because of their actual fitness, but on the basis of showy ornaments like peacock’s tails or complex songs. Finally, many organisms have cultural behaviours such as tool use, and these feed back onto traditional evolutionary processes like natural selection.

Evolution is also chaotic, meaning that the changes it produces are not always predictable, This is partly because it relies on random mutations to produce the raw material on which natural selection can act. More controversially, it has been argued that natural selection has a kind of memory that allows it to swiftly recreate old solutions when they are needed.

Nowadays there is also a new force in evolution: humans. We are exerting new selection pressures on many species, changing them in unpredictable ways.

Do humans experience natural selection?

These studies have typically found that natural selection has been operating in contemporary humans (9, 11–14). It has also been shown that there was significant variance in relative fitness in a preindustrial human population, such that there was much potential for natural selection (15).

Are humans currently in natural selection?

Natural selection is still happening in humans – As much as we have made things easier for ourselves, there are still selection pressures around us, which mean that natural selection is still happening. Like all mammals, humans lose the ability to digest milk when they stop breastfeeding.

  1. This is because we stop making an enzyme called lactase.
  2. In some countries, the population has acquired ‘lactase persistence’, meaning that people make lactase throughout their lives.
  3. In European countries we can thank one specific gene variation for our lactase persistence, which is called ‘-13910*T’.

By studying this specific gene variation in modern and ancient DNA samples, researchers suggest that it became common after humans started domesticated and milking animals. This is an example of natural selection where we have actually made the selection pressure ourselves – we started drinking milk, so we evolved to digest it! Another example of humans undergoing natural selection to adapt to a lifestyle is the Bajau people, who traditionally live in houseboats in the waters of South East Asia and spend much of their lives diving to hunt fish or collect shellfish.

How does natural selection explain human behavior?

Does Evolution Explain Our Behaviour? Does evolution explain our behaviour? The short answer is: No. And you may well concur with that answer but ‘out there’ there is an increasing constituency of thinkers claiming quite otherwise. Along with the claims that the brain explains the mind and activity in one bit of brain or another corresponds to love, joy, conscience, the self, or whatever, and that much of our behaviour is explained by a gene for this or a gene for that, is the increasingly popular notion that our behaviour has an evolutionary explanation.

  • Indeed you can hardly open a newspaper without encountering some manifestation or other of ‘evolutionary psychology’.
  • Raymond Tallis’ presentation at the 2008 Autonomy, Singularity, Creativity conference.
  • Evolutionary psychology assumes that human behaviour is being shaped, indeed determined, by processes of natural selection: those modes of behaviour that favour the replication of the genome will preferentially survive.

We behave as we do because we are designed to optimise the chances of our surviving long enough to replicate our genetic material. Men who sleep with a lot of women, traders who aim to maximise their returns on their investments – or at least attempt to – are simply responding to the fundamental biological imperative to make the world safe for their genes.

You may think that you chose your mate because she was kind, and witty, and shared your view of the world. Forget it: you were attracted to her because she had a waist/hip ratio (the ratio of the circumference of the waist to that of the hips) that approximated to the 0.7 – a figure which is associated with good health and fertility.

As for your political or religious beliefs (if you have them), they possess you because they improve your chances of survival or that of the group to which you belong. You haven’t chosen them; they have chosen you. If you think this is somewhat tendentious, consider the recent claim is that evolutionary psychology can explain why pink is associated with femininity and blue with masculinity.

  1. Women in prehistory were the principal gatherers of fruit and would have been sensitised to the colours of ripeness – i.e.
  2. Deepening shades of pink.
  3. Men, on the other hand, would have looked for good hunting weather and sources of water – both of which are connected with blue.
  4. Not everyone is persuaded by the terribles simplificateurs who preach the gospel of evolutionary psychology; and I include myself among them.

The initial attractiveness of the notion that it is our genes, and not our thoughts, or our conscious agency that guide our lives is understandable. Has not Darwin demonstrated that human beings were manufactured by the same processes as gave rise to chimpanzees, sea slugs and centipedes? And are we not living now because we have bodies and behaviours that maximise our individual or collective fitness? What makes us think that human beings engaged in the manifestly biological act of choosing a mate are any different from other creatures engaged in the same activity? Well the facts of everyday life, for a start.

  1. The enormously complex events that result in two individuals deciding to share their lives, consisting to an important degree of a very long sequence of conversations, has no counterpart in the pair-bonding processes even of our nearest primate kin.
  2. This seems so obvious that you may wonder why anyone gives evolutionary psychology the time of day.

It is easy, however, to persuade of the truth of this pseudo-science if we describe animal behaviour in anthropomorphising terms and human behaviour in ‘animalomorphic’ terms. Words such as ‘mating behaviour’, ‘courtship’, and so on, shuttle back and forth between the human world and the animal kingdom.

  1. We can see this linguistic pincer movement closing on the gap between humans and animals at work everywhere in evolutionary psychology.
  2. Let us look at the first strategy because it is particularly effective.
  3. Indeed, we have got so used to re-describing what goes on in ordinary human life in such a way as to make it sound like what goes on in ordinary animal life, that we no longer notice ourselves doing it.
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Here are a couple of examples. Supposing you invite me out for a meal. Having learnt that the credit crunch has turned your house into a mound of negative equity, I choose the cheapest items on the menu and falsely declare that I am full after the main course, so as to spare you the expense of a pudding.

  1. A chimpanzee reaches out for a banana and consumes it.
  2. Evolutionary psychologists would like to say that both the chimp and I are doing similar things: we are exhibiting “feeding behaviour”.
  3. This identity of description, however, obscures huge differences between the chimp’s behaviour and mine.
  4. Here’s another example.

I decide to improve my career prospects by signing up for a degree course which begins next year. I have a small child. I therefore do more baby-sitting this year in order to stockpile some tokens. Daisy the cow bumps into an electric wire and henceforth avoids that place.

  • It could be said that both Daisy and I have been exhibiting learning behaviour.
  • Again, I think you will agree, the difference between the two forms of behaviour is greater than the similarities.
  • Those who wish to obliterate the gap between humans and other beasts not only try to make human behaviour beast-like.

They also describe animal behaviour anthropomorphically, making it seem to be human-like. We are all familiar with Walt Disney- like descriptions of animals that impute to them all manner of abstract or factual knowledge and institutional sentiments for which there is evidence only in human beings.

This exemplifies a wider error that I have christened the Fallacy of Misplaced Explicitness that enables thinkers to speak of squids classifying the contents of the world, wasps grieving for their young and even artefacts such as thermostats making judgements. One of the motives behind this is a feeling that, since we are animals in so many respects, unsentimental honesty requires us to say that we are just like animals in all respects.

Like animals we are ejected from our mother’s bodies at birth and like animals we die of physiological failure; like animals, we eat, defaecate, copulate, fight and so on. But this is beside the point; for it does not follow that we eat, defaecate, copulate, fight.

etc., like animals. It is a mistake, by the way, to look for our uniqueness solely in higher manifestations of humanity – such as religion, art, science and creativity. It concedes too much and overlooks that our uniqueness is there in every aspect of our lives: all of the biological givens are utterly transformed in us.

We do not even defaecate like animals. Or not by choice, anyway. We insist on a certain amount of privacy – often in facilities with light switches that are connected to fans driven by artifacts based in the mighty science of electromagnetism to take away the pong.

And we are the only beasts who manufacture toilet paper and argue over the respective merits of different brands of it. Even human dying is profoundly different from animal dying, except at the very end, when we become more like other stricken beasts. And when it comes to mating, we are the only beasts who make love.

Every seemingly animal need or appetite – for food, water, and warmth – is utterly transformed in humans. And many of our strongest appetites – for example, for acknowledgement of what we are in ourselves, for abstract knowledge and understanding – are unique to us.

  1. Only humans think about the distinctive features of their own species.
  2. Even evolutionary psychologists can occasionally see what is in front of their noses and notice that we are a bit different.
  3. They acknowledge that it was no mere coincidence that the organism that saw how all organisms came about and wrote The Origin of Species was a human being rather than, say, a chimp or a centipede.

Undaunted, evolutionary psychologists look for ways to fill the Great Ditch separate humanity from animals and human behaviour from animal behaviour. The land-fill they need to make their approach to human behaviour seem half way plausible is provided by the concept of the ‘meme’, introduced by Richard Dawkins over thirty years ago, but now ubiquitous, like Dawkins himself.

The meme is a notion designed to cope with the fact that human lives are filled with, and are shaped by and shape, cultural phenomena that have no counterparts in the natural word. It is supposed to be analogous to a gene. While the gene is a self-replicating unit by which biological characteristics are transmitted, the meme is a self-replicating unit by which cultural characteristics are transmitted.

Dawkins gives as examples ‘tunes, catch phrases, clothes, ways of making pots or building arches’. The enormously influential philosopher Daniel Dennett believes that human consciousness is a huge complex of memes. The key feature of memes for evolutionary psychologists is that they replicate by occupying human minds, which accept them as passively as does a brain invaded by a virus.

  1. We do not choose our memes; our memes choose us.
  2. They are advantageous to themselves but not necessarily to us; for their whole raison d’être – not only the reason for their existence but the reason that they exist at all – is that they are able to find minds in which to replicate.
  3. This is a desperate attempt to ‘save the appearances’ in the face of a theory – the notion that evolution determines our behaviour – that has difficulty accommodating them.

Just how desperate is manifested in some of Dennett’s examples of memes: the SALT agreement, faith, and tolerance for free speech. It is difficult to think of ‘tolerance for free speech’ as something that infests my passive mind as a unit, On the contrary, it is a principle that is argued over within and between people, and whose scope is likewise debated.

  • It requires active, conscious assent on each occasion.
  • Even the simpler memes – such as a tune in one’s head – are often discretionary: I bet the tunes in my head and the tunes in yours are not the same; or the same in my head from day to day or hour to hour.
  • And many so-called memes – ideas for example – far from being passively acquired, indeed inescapable and unchosen as genes are, require hard work.

Meme theory, which sidelines human agency – and pictures the human mind as something between a junk yard and a lumber room – is the reduction to absurdity of evolutionary psychology. It is an example of what happens when science gives way to scientism; when evolutionary theory spawns evolutionary psychology.

How does natural selection act on behavior?

Summary –

  • Most animal behaviors are controlled by both genes and experiences in a given environment.
  • To the extent that behaviors are controlled by genes, they may evolve.
  • Behaviors that improve fitness increase through natural selection.

How does natural selection affect human Behaviour?

Evolutionary psychology uses evolutionary theory to explain similarities in psychological characteristics. According to evolutionary psychologists, patterns of behavior have evolved through natural selection, in the same way that physical characteristics have evolved.

What’s the opposite of natural selection?

Artificial selection is the identification by humans of desirable traits in plants and animals, and the steps taken to enhance and perpetuate those traits in future generations.

What is the strongest survive theory?

survival of the fittest, term made famous in the fifth edition (published in 1869) of On the Origin of Species by British naturalist Charles Darwin, which suggested that organisms best adjusted to their environment are the most successful in surviving and reproducing.

Why is it called natural selection?

Definition and explanation – Natural selection is the process by which the natural environment causes different organisms to survive or die based on their different traits It’s where the term “survival of the fittest” comes from. Natural selection is one of the key driving forces behind evolution – the process by which species become better adapted to their environment over long periods of time.

It’s called ‘natural selection’ because it’s a way of selecting organisms with certain traits that’s driven completely by nature, compared to ‘artificial selection’ such as when humans breed sheep to become more wooly and more tame by deliberately cross-breeding and selecting for desirable-to-humans traits.

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There’s a lot of variation between and within animal species (just think of the variation between different breeds of pet dogs). In the wild, this variation between animals gives each one of them a better or worse chance at surviving; maybe one bird has a slightly longer beak that lets it get worms out of the ground more easily.

  • This variation means that animals with some traits (such as a long, pointy beak) are more likely to survive and reproduce, while others will die (because resources are limited in the wild and so there is a competition to survive).
  • When an animal reproduces it passes on its character traits to its children via its genes, which are physically stored in DNA.

This means that over time certain traits that are useful for survival in the wild are positively selected for, and traits that are unhelpful are negatively selected for (via natural selection!). This process is how species evolve to succeed in their environment.

What is the most common natural selection?

EVOLUTION / TYPES OF NATURAL SELECTION =Stabilizing selection= Within a population most variation can be fitted to a bell curve. For instance, in the image below, a group of people have been arranged based on height with the shortest on the left and the tallest on the right.

  1. You can clearly see that the majority of individuals are clustered somewhere in the middle and fewer individuals at each end of the range.
  2. Stabilising selection is probably the most common type of natural selection; it favours the most common phenotype as the best adapted.
  3. Stabilising selection reduces variation by selecting against alleles that produce more extreme phenotypes at either end of the phenotypic range.

The resulting bell shaped curve is narrower. A good example is birth weight. Babies that are too light are often under-developed and therefore have a reduced chance of survival. Babies that are too heavy are usually larger and therefore they may be an increased risk of complications during birth.

=Directional selection= This type of natural selection is most common during periods of ”’environmental change”’. Directional selection favours alleles that produce phenotypes at one extreme of a phenotypic range. Selection reduces variation at one extreme of the range while favouring variants at the other end.

The resulting bell shaped curve shifts in the direction of the selection. For instance a population of snails may exhibit some variation in shell colour. Directional selection might act against the lightest coloured individuals, reducing the frequency of alleles that code for lighter colours.

  • =Disruptive selection= Disruptive selection favours alleles that code for phenotypes at both extremes of a phenotypic range.
  • The bell shaped curve acquires two peaks.
  • Disruptive selection may occur when environmental conditions are varied or when the population covers a large area.
  • For instance, a population of snails might live in a region that has areas with white rocks and areas with black rocks.

Disruptive selection would act against the individuals with intermediate colours (grey or beige individuals), reducing the frequency of alleles that code for these colours. Disruptive selection can result in two distinct groups and if they become adapted to a different way of life (niche) they could eventually evolve into separate species (speciations).

Which scenario is an example of natural selection?

Natural selection is the process through which organisms with greater environmental adaptations survive and reproduce more. After industrialization, the proportion of dark-winged moths rose, an example of natural selection.

What is not an example of natural selection?

The correct answer is: Bacterial populations in hospitals acquire resistance to antibiotics used to treat illness.

Which of these is an example of natural selection?

So, the correct answer is ‘ The venom of a certain salamander species becoming more poisonous as predation by snakes increases ‘.

What are the 3 types of natural selection and examples?

Directional Selection, Stabilizing Directional and Disruptive Selection Directional selection, stabilizing selection and disruptive selection are three types of natural selection. They are also examples of adaptive evolution. Natural selection is the mechanism of evolution which favors organisms that are better adapted to their environments.

  1. Such organisms tend to survive longer and produce more offspring.
  2. Selection pressures act against organisms that do not have favorable traits and they are removed from the population.
  3. As a result, natural selection plays a major role in the creation of new species over time.
  4. The English naturalist and scientist Charles Darwin was the first to describe directional selection as a form of natural selection in his foundational 1859 work On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life.

The directional selection theory says that an extreme phenotype (characteristics or traits) is favored over other phenotypes and this causes the allele frequency (how often the variant of a gene shows up in a population) to shift over time in favor of the extreme phenotype.

  • In other words, if a particular trait is favorable, it will be expressed at the most beneficial frequency in the population.
  • An example of directional selection is giraffe neck lengths.
  • The environment created a selection pressure which favored giraffes with longer necks who could reach more food in the trees.

At the same time, there was selection pressure against giraffes with shorter necks. Both long and short necks are extreme phenotypes, but over time, the long neck phenotype dominated due to selection pressure, i.e., this trait in giraffes shifted toward the direction of long necks.

  1. Stabilizing selection can be thought of as “middle-of-the-road” selection, meaning a non-extreme trait is favored instead of one of the two extreme traits.
  2. An example of this is plant height.
  3. In a population of plants, those that are short may not get enough sunlight, but those that are tall may be subjected to wind damage.

This results in an increase in the number of medium-height plants and a decrease in very tall and very short plants. Because most traits do not change drastically over time, stabilizing selection is considered to be the most common mechanism for natural selection.

  • Other examples of stabilizing selection are the birth weight of humans and the number of eggs a bird lays (clutch size).
  • The birth weight of human babies stays within a certain range because babies that have a very low birth weight have less chance of survival and those with a very high birth weight can cause complications during delivery which threaten the life of the mother and the child.

The clutch size of bird species is limited to a certain number of eggs. There must be enough eggs so that the clutch can survive predation and/or disease, but not so large that there are too many chicks for the parent(s) to feed. This type of natural selection is bimodal and favors both extreme traits in a population.

  • For example, in a population of plants, there are some pollinators that visit the tallest plants, a different species of pollinator visits medium-height plants and a third species of pollinator that prefers the shortest plants.
  • If the pollinator that prefers medium-height plants is removed, natural selection would select against medium-height plants and the overall plant population would move toward having only tall and short plants, the two extreme phenotypes.

A more classic example of disruptive selection is the beak size of finches on the Galapagos Islands that was studied by Darwin. Because the majority of seeds found on some of the islands were either large or small, finches with large and small beaks (no medium-sized beaks) were favored on those islands.

Directional Selection Stabilizing Selection Disruptive Selection
Decreases genetic variance in a population No Yes No
Expresses extreme traits Yes No Yes
Number of traits favored 1 1 2
Most common mechanism of natural selection No Yes No
Type of selection mechanism effecting the beak size of Galapagos finches No No Yes

The image above shows the three patterns of natural selection using an allele that determines fur color.

Which scenario is an example of natural selection?

Natural selection is the process through which organisms with greater environmental adaptations survive and reproduce more. After industrialization, the proportion of dark-winged moths rose, an example of natural selection.