Evolution Grade 12 Term 3 Revision Notes: Life Sciences As students gear up for their Grade 12 Term 3 examinations in Life Sciences, mastering the intricate topic of evolution is crucial. Evolution, the cornerstone of modern biology, encompasses the diversity of life on Earth and the processes that drive it. To aid in your revision journey, we’ve compiled comprehensive revision notes focusing on key concepts and principles in evolutionary biology.
What is Evolution?
The word evolution simply means change over time. Evolution is the process by which organisms develop over time from earlier forms. Biological evolution refers to any genetic change in a population that is inherited and becomes a characteristic of that population over several generations.
Watch Video Lesson: Evolution: Life Sciences Grade 12
Key Terminologies in Evolution Section for Grade 12 Learners to know
- biological evolution: any genetic change in a population that is inherited over several generations
- biological species: a group of organisms with similar characteristics that interbreed with one another to produce fertile offspring
- population: a group of individuals of the same species occupying a particular habitat
- punctuated equilibrium: evolution characterised by long periods of little or no change followed by short periods of rapid change
- natural selection: mechanism of evolution – organisms survive if they have characteristics that make them suited to the environment
- artificial selection: human-driven selective force, e.g. breeding of plants and animals to produce desirable traits
- inbreeding: mating of individuals that are closely related
- outbreeding: mating of individuals that are not closely related
- speciation: the formation of a new species
- geographic speciation: formation of a new species when the parent population separated by a geographical barrier