Evolution and Genetics Overview

Evolution and Mechanisms of Evolution

• Genetic diversity increase: Mutation is most likely to increase genetic diversity in a population.
• Artificial vs. Natural Selection: Artificial selection is guided by humans, while natural selection occurs without human intervention.
• Vestigial Structure: A vestigial structure is a structure that has lost its original function over time.
• Directional Selection: An increase in beak size in a bird population during a drought is an example of directional selection.

Genetics and Population Evolution

• Meiosis vs. Mitosis: Meiosis results in four non-identical daughter cells, while mitosis results in two identical cells.
• Genotype vs. Phenotype: Genotype describes an organism's genetic makeup, whereas phenotype describes its observable characteristics.
• Genetic Drift: Genetic drift is a random change in allele frequencies due to chance events, particularly prominent in small populations.

Ecology

• Keystone Species: A keystone species has a disproportionate impact on its ecosystem relative to its abundance.
• Survivorship Curve: A survivorship curve depicts the percentage of a population that survives at different ages.
• r-selected Species: r-selected species are characterized by high reproduction rates and short lifespans.

Speciation and Phylogeny

• Sympatric Speciation: Sympatric speciation occurs without geographic isolation; often due to reproductive barriers.
• Cladogram Node: In a cladogram, a node represents the common ancestor of the organisms depicted.

Behavioral Ecology

• Proximate vs. Ultimate Causes: Proximate causes refer to the immediate triggers of behavior, while ultimate causes refer to the evolutionary reasons.
• Learned Behavior: An example of a learned behavior is a dog learning to sit on command.

Plant Biology and Photosynthesis

• Plant Adaptation to Land: Plants require a waxy cuticle to prevent water loss to survive on land.
• Primary Growth: Primary growth in plants involves cell elongation in roots and stems.
• Chlorophyll's Role: Chlorophyll absorbs sunlight, converting carbon dioxide and water into glucose during photosynthesis

True or False

• Sexual Selection: Sexual selection is a form of natural selection that improves an individual's mating chances (True).
• Fungi: Fungi are not autotrophic; they are heterotrophic (False).
• Allopatric Speciation: Allopatric speciation occurs when populations are geographically isolated (True).