1. Industrial melanism, a prime example of natural selection studied by Kettlewell, involved two UK peppered moth varieties: Biston betularia and Biston carbonaria. 2. In pre-industrial Britain, Biston betularia outnumbered Biston carbonaria. B. Betularia was greyish-white, while B. carbonaria had a melanic form. 3. Nocturnal moths rested on tree trunks during the day. White-winged moths … Read more
1. Adaptive radiation, a pivotal process in evolution, entails the transformation of an original species into a diverse array of varieties. 2. A notable illustration of adaptive radiation is found in Darwin’s Finches. During Charles Darwin’s exploration of the Galapagos Islands, he observed a variety of small birds known as finches. 3. Darwin’s observations suggested … Read more
The wings of a butterfly and a bat are analogous, meaning they share similar functions but do not have a common evolutionary origin. Examples of analogous structures include: 1. Butterfly wings and bird wings may appear similar, but they are not anatomically alike, despite serving similar functions. 2. The eyes of an octopus and mammals … Read more
Disruptive selection, also referred to as diversifying selection, occurs when genetic changes in a population favor extreme trait values rather than intermediate ones. This leads to an increase in the variation of the trait, causing the population to split into two distinct groups. Examples of disruptive selection include the beak size variation among Galapagos finches … Read more
1. Hugo de Vries found significant variations, with major changes linked to chromosomal issues and smaller changes to gene mutations. 2. Mutations happen slower than what’s needed for evolution to bring about significant transformations. 3. Chromosomal problems are unstable and often lead to sterile organisms, limiting their impact on evolution due to challenges in reproduction.
1. Fossils are the remains of ancient plants and animals found in different layers of the Earth. 2. The study of fossils gives us strong and direct proof of how evolution works. 3. Fossil studies show that life forms were not the same millions of years ago. 4. The geological timescale, which helps us understand … Read more
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The four major factors that are responsible for changing gene frequency are as follows: 1. Gene mutations :induce hereditary alterations either in a solitary gene or across an entire chromosome. 2. Natural selection:instigates modifications in the gene frequency within a population, subsequently fostering evolutionary changes over time. 3. Migration :engenders the relocation of populations, facilitating … Read more
Genetic drift is the random alteration of gene frequencies in a population due to chance, particularly prominent in small populations. 1. Founder effect occurs when a portion of the population, isolated or migrated, develops genetic distinctions from the original due to allelic frequency changes, potentially leading to the emergence of a new species. 2. The … Read more
Australopithecus is characterized as having a brain resembling that of an ape.