Evolution

• Life history traits are traits related to timing of development and reproduction, longevity, and number/size of offspring.
• Behavioural traits can have a phenotype related to the behaviour of an individual/species.
• Morphological traits are traits where the phenotype has to do with the shape, structure, colour, pattern, or size of an individual/species.
• Height is a morphological trait.
• Traits are sexually dimorphic if they vary between biological sexes in a species.
• Heritability is a measure of how important genetics are to determining a trait.
• Biological traits are the observable characteristics of an individual that manifest in different ways and can be categorized in certain ways, but are usually more complex than our simplified categorizations.
• Biology can be organized by taxonomy or more general levels of organization (from molecules to the biosphere).
• Diversity and variation can be measured and analyzed across different levels of organization.
• Biodiversity usually refers to the total number of different species.
• Phenotypic plasticity: When the exact same genotype produces different phenotypes under different environments.
• Evolution is the process that results in changes in the proportion of heritable traits within populations from one generation to the next.
• Adaptations are traits that provide a “fit” between an organism and its environment.
• Mutations occur when a change takes place within an individual’s genes.
• While most mutations do not impact phenotype (they are silent), mutations occasionally arise that do alter phenotype.
• Adaptations make it look like selection is driven by “needs”.
• Selection increases the frequency of currently adaptive traits.
• “Fitness” is a term most often used by biologists to explain the evolutionary success of certain organisms.
• Populations do not adapt because they “need” to - natural selection lags behind environmental change.
• Differential reproduction/survival occurs based on that phenotypic variation.
• “Fitness” is a term most often used by biologists to explain the evolutionary success of certain organisms.
• The “fittest” organisms are most successful at passing on their genes.
• Fitness is a measure of how many surviving offspring an organism produces - not a measure of traits like ‘strongest’ or ‘fastest’.
• Traits that increase reproduction are adaptive.
• Selection acts on phenotype – but results in changes in genetic variation.
• Evolution is the process that results in changes in the proportion of heritable traits within populations from one generation to the next.
• Directional selection is when the distribution of a trait moves in a single direction.
• Stabilizing selection is when genetic variants that lead to 'extremes' become less common in the population over time due to trade-offs.
• Alleles are different versions of information that could be encoded for a given gene.
• Natural selection can alter population variance several ways, it can shift it in one direction (directional selection), it can reduce/maintain variation (stabilizing selection), or it can favor more 'extreme' values (disruptive selection).
• Mutations are random, not directed toward needs or fitness.
• Gene flow represents the transfer of genetic material from one population to another and tends to make populations look similar to each other.
• Genetic drift causes shifts in allelic frequencies by random chance.
• Mutations are a source of new genetic variation.
• Smaller populations are more strongly affected by genetic drift than larger populations.
• Genetic drift is the change in allele frequencies that happens through random chance, not tied to survival and reproduction, and is always happening.
• A clade that is not monophyletic is paraphyletic, as it includes a common ancestor and a subset of its descendants.
• Phylogeny is based on common ancestry and species are more closely related if they have a more recent common ancestor.
• A clade is a group of species that share a common ancestor and all of its descendants, and is monophyletic.
• The most distantly related taxa to other terminal nodes on the tree are referred to as the most distantly related species.