Search results
fineartamerica.com
- Homo sapiens, like all species, has been shaped by positive natural selection. As first articulated by Darwin and Wallace in 1858, positive selection is the principle that beneficial traits—those that make it more likely that their carriers will survive and reproduce—tend to become more frequent in populations over time (1).
www.science.org/doi/10.1126/science.1124309
People also ask
What is positive natural selection?
What does natural selection mean?
How does natural selection work?
How does natural selection affect a person's survival?
Does positive natural selection shape the human genome?
Is positive selection the only component of evolution?
Positive natural selection, or the tendency of beneficial traits to increase in prevalence (frequency) in a population, is the driving force behind adaptive evolution.
Natural selection is a process by which a species changes over time in response to changes in the environment, or competition between organisms, in order for the species to survive. The members...
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.
- Teleology and The “Function Compunction”
- Anthropomorphism and Intentionality
- Use and Disuse
- Soft Inheritance
- Nature as A Selecting Agent
- Source Versus Sorting of Variation
- Typological, Essentialist, and Transformationist Thinking
- Events and Absolutes Versus Processes and Probabilities
Much of the human experience involves overcoming obstacles, achieving goals, and fulfilling needs. Not surprisingly, human psychology includes a powerful bias toward thoughts about the “purpose” or “function” of objects and behaviors—what Kelemen and Rosset (2009) dub the “human function compunction.” This bias is particularly strong in children, w...
A related conceptual bias to teleology is anthropomorphism, in which human-like conscious intent is ascribed either to the objects of natural selection or to the process itself (see below). In this sense, anthropomorphic misconceptions can be characterized as either internal (attributing adaptive change to the intentional actions of organisms) or e...
Many students who manage to avoid teleological and anthropomorphic pitfalls nonetheless conceive of evolution as involving change due to use or disuse of organs. This view, which was developed explicitly by Jean-Baptiste Lamarck but was also invoked to an extent by Darwin (1859), emphasizes changes to individual organisms that occur as they use par...
Evolution involving changes in individual organisms, whether based on conscious choice or use and disuse, would require that characteristics acquired during the lifetime of an individual be passed on to offspringFootnote 12, a process often termed “soft inheritance.” The notion that acquired traits can be transmitted to offspring remained a common ...
Thirty years ago, widely respected broadcaster Sir David Attenborough (1979) aptly described the challenge of avoiding anthropomorphic shorthand in descriptions of adaptation: Unlike many authors, Attenborough (1979) admirably endeavored to not use such misleading terminology. However, this quote inadvertently highlights an additional challenge in ...
Intuitive models of evolution based on soft inheritance are one-step models of adaptation: Traits are modified in one generation and appear in their altered form in the next. This is in conflict with the actual two-step process of adaptation involving the independent processes of mutation and natural selection. Unfortunately, many students who esch...
Misunderstandings about how variation arises are problematic, but a common failure to recognize that it plays a role at all represents an even a deeper concern. Since Darwin (1859), evolutionary theory has been based strongly on “population” thinking that emphasizes differences among individuals. By contrast, many naïve interpretations of evolution...
A proper understanding of natural selection recognizes it as a process that occurs within populations over the course of many generations. It does so through cumulative, statistical effects on the proportion of traits differing in their consequences for reproductive success. This contrasts with two major errors that are commonly incorporated into n...
- T. Ryan Gregory
- rgregory@uoguelph.ca
- 2009
In natural selection, genetic mutations that are beneficial to an individual’s survival are passed on through reproduction. This results in a new generation of organisms that are more likely to survive to reproduce.
If one species or lineage has many functional changes in a gene compared to its relatives, we say that the gene is under positive selection. If there are very few functional changes between distantly related species, we say that the gene is under purifying selection.
