Evolutionary Biology and Phenotypic Evolution Flashcards

This set of vocabulary flashcards covers the fundamental principles of evolutionary biology, historical figures, the timeline of life on Earth, and the mechanisms of adaptation and inheritance.

Evolution

A change in the frequency of an allele or genotype within a population over time.

Allele

A unique copy of a gene.

Genotype

Individuals that share the same set of alleles at one or more loci.

Population

A group of interbreeding individuals.

Phenotype

The observable traits or characteristics of an organism, such as eye colour, height, weight, or behaviour.

Phenotype Formula

$$\text{Phenotype} = \text{genotype} + \text{environment}$$

Acquired characters

Traits developed during an organism's lifetime that cannot be passed onto offspring through genes.

Mutation

The origin for all heritable variation.

Five mechanisms of evolutionary change

Mutation, natural selection, genetic drift, gene flow, and non-random mating.

Speciation

The origin of two or more species from a single common ancestor.

Artificial selection (selective breeding)

A process where humans produce crops and livestock with desirable traits, such as the evolution of Teosinte into modern corn (maize).

Tree of Life

A representation showing how all species are connected through ancestry and share a common ancestor.

Earth's Formation Date

Approximately $4.568$ billion years ago.

LUCA

The Last Universal Common Ancestor ($3.5 - 4.0$ billion years ago), which is the most recent ancestor shared by all living organisms today.

Bacteria

Single-celled prokaryotes that appeared $2.6 - 3.5$ billion years ago, including cyanobacteria.

Archaea

Single-celled prokaryotes distinct from bacteria, appearing $2.6 - 3.5$ billion years ago and often found in extreme environments.

Eukarya

Organisms with nuclei and membrane-bound organelles, appearing $1.8 - 2.0$ billion years ago; includes animals, plants, fungi, and protists.

Phylogeny

An evolutionary tree showing relationships among organisms where the root represents the common ancestor.

Proterozoic Eon

The period from about $2.5$ billion to $541$ million years ago characterized by increasing oxygen levels and the evolution of early eukaryotes.

Stromatolites

Microbial life forms that dominated the oceans during the Proterozoic Eon.

Tetrapods

Four-limbed vertebrates that evolved from fish-like ancestors about $370$ million years ago.

Amniota

A group of vertebrates characterized by the evolutionary innovation of the amniotic egg and strengthened digits.

Archaeopteryx

An important transitional form between dinosaurs and birds.

Human-Chimpanzee common ancestor

A shared ancestor that lived approximately $4.5 - 6$ million years ago.

Macroevolution

Evolutionary change of large-scale traits and structures across taxa, occurring above the species level over thousands to millions of years.

Microevolution

Change in allele frequencies within a population over shorter time scales, driven by mechanisms like natural selection and genetic drift.

Adaptive radiation

The diversification of species from a common ancestor into many different forms with specialized traits, such as Darwin's finches.

Carl Linnaeus

Developed the hierarchical classification system (Kingdom to Species) and the system of binomial nomenclature.

Jean-Baptiste Lamarck

A scientist who correctly proposed that species change over time but incorrectly suggested that acquired characteristics are inherited genetically.

Descent with modification

Darwin's proposal that species change over time and new species arise from ancestral species through common ancestry.

Alfred Russel Wallace

A scientist who independently developed similar ideas about natural selection at the same time as Charles Darwin.

The three conditions for Natural Selection

1. Variation 2. Heritability 3. Differential Reproductive Success (fitness).

Gregor Mendel

Scientist who studied pea plants and discovered predictable patterns of inheritance, providing the genetic mechanism Darwin lacked.