Biological Evolution Part 1 Flashcards

Vocabulary flashcards covering biological classification, phylogeny, species concepts, theories of evolution, and artificial selection based on the provided H2 Biology lecture notes.

Biological classification

The organisation of species according to shared characteristics, involving naming, identification, and classifying organisms.

Binomial nomenclature

A system where each organism has a scientific name in Latin consisting of a capitalized Genus name and a lower case species name, always italicized or underlined.

Taxon

A taxonomic category or level in the hierarchical classification system, such as Kingdom, Phylum, Class, Order, Family, Genus, or Species.

Order of hierarchical classification

Kingdom, Phylum, Class, Order, Family, Genus, Species (often remembered by the mnemonic "King Philip Came Over For Granny’s Soup").

Phylogeny

The evolutionary history and organisation of species according to evolutionary relationships based on similarities and differences in physical or genetic characteristics.

Sister groups

Two descendants that split from the same branch point or node in a phylogenetic tree, representing each other's closest relatives.

Clade

A group of species that includes an ancestral species and all its descendants.

Cladogram

A type of phylogenetic tree that shows the pattern of homologous shared derived characteristics among taxa.

Shared derived traits

Traits that are unique to a group and have changed from the ancestral form, such as the single-toed hoof of modern horses.

Biological species concept

The definition of a species as a group of closely related organisms capable of interbreeding to produce fertile and viable offspring, while being reproductively isolated from other species.

Lamarckism

The now-rejected theory of the heritability of acquired characteristics, suggesting anatomical structures develop through constant use and are passed to offspring.

Natural selection

The process by which the environment selects individuals with traits (adaptations) that confer a survival advantage, leading to higher reproductive success and changes in trait frequency over generations.

Adaptations

Traits that confer an advantage to individuals, allowing them to leave more offspring in a specific environment.

Neo-Darwinism

A modification of Darwin's theory that incorporates Mendelian genetics, including knowledge of gene mutations, chromosomal mutations, and allele frequencies.

Survival of the fittest

A term describing individuals that possess traits most suited or adapted for survival in their specific environment, though they may not necessarily be the "fittest" in a general sense.

Geographical isolation (Allopatric speciation)

A method of separating a population from the main group by physical barriers to prevent interbreeding, leading to the formation of new species.

Artificial selection

The intentional manipulation by humans of the physical characteristics of individuals in a population through controlled breeding to produce a desired response.

Inbreeding

Selective reproduction between closely related organisms (e.g., offspring of same parents) to propagate desirable characters, which can reduce genome variability and lead to reduced vigor.

Outbreeding

Selective reproduction between individuals from genetically distinct populations or different varieties/strains.

Hybrid vigor (Heterosis)

The superiority of hybrid progeny over parent stocks, characterized by increased resistance or size, usually due to an increase in heterozygosity.

Colchicine

An alkaloid applied to plant buds to produce tetraploid ($4n$) branches, which produce diploid ($2n$) gametes.

Tetraploid hybrid example

The rutabaga ($4n=38$) is a fertile hybrid between the turnip ($n=10$) and cabbage ($n=9$).