What is evolution?
Evolution is the change of the genetic composition (gene pool) of a population over time that produces new species from ancestral species. A 'population' refers to a group of organisms of one species that can interbreed to produce viable, fertile offspring. The development of adaptations through mutations or sexual reproduction are then acted upon by selection pressures from environmental factors, which select for the trait that makes the organism best adapted to that environment. Thus, the allele frequency for the favourable phenotype will increase in the population.
Biological Evolution
Biological evolution occurs through events that cause changes in the allele frequencies of a population over time.
Natural selection is the process by which organisms who are biologically fitter because they have favourable phenotypic traits ( which means that they are well adapted to the selection pressures that they are exposed to in that environment) are more likely to survive, reproduce and pass their alleles to the next generation (Darwin, 1859). Thus, the allele frequency for the favourable trait will increase in the population over time. Genetic drift is caused by chance events that cause a change in the gene pool of a population and therefore a change in the allele frequencies of the population over time. Gene flow involves the movement of alleles into (immigration) or out of (emigration) a population via migration. Therefore, this can change the allele frequency of the population if an unrepresentative sample of the original population migrates. Mutations can be spontaneous as they can be caused by errors in DNA replication or induced by mutagens, such as ultraviolet radiation. Mutations create new alleles, which can cause new adaptations to arise in a population. |
Cultural Evolution
When hominins diverged from apes, the location of the foramen magnum progressively became more anterior, allowing for an upright gait. Approximately 180,000 years ago, modern homo sapiens evolved and developed a long throat, flexible tongue and a smaller mouth. As the tongue moved down, the larynx was also pulled lower (Masterson, 2010). These adaptations enabled Homo sapiens to develop the complex motor skill of articulating speech and enabled humans to communicate with other humans.
Cultural evolution is the result of learned behaviour that is transmitted socially through generations via the development of customs and languages. Examples of cultural evolution include the transfer of stories through art or the ritual of burying the dead
Cultural evolution is the result of learned behaviour that is transmitted socially through generations via the development of customs and languages. Examples of cultural evolution include the transfer of stories through art or the ritual of burying the dead
Technological Evolution
Technological evolution refers to the development of tools that gives humans more control over their environment.
The Mousterian tools depicted in figure 1.4 compared to the power tools illustrated in figure 1.5 highlights the technological advancements that hominin species have undergone. For example, the power tools exhibited in figure 1.5 could have been used to build classrooms in a school, where young humans are taught about language, culture, history and everything in between. In addition, the development of electronic devices, such as the iPhone 7 enables humans on opposite sides of the world to communicate. Thus, technological evolution perpetuates cultural evolution.
The Mousterian tools depicted in figure 1.4 compared to the power tools illustrated in figure 1.5 highlights the technological advancements that hominin species have undergone. For example, the power tools exhibited in figure 1.5 could have been used to build classrooms in a school, where young humans are taught about language, culture, history and everything in between. In addition, the development of electronic devices, such as the iPhone 7 enables humans on opposite sides of the world to communicate. Thus, technological evolution perpetuates cultural evolution.