Intro to Evolution and Darwin (Notes)

Definition of Evolution

Change over time in organisms; a core theme in biology explaining similarities and differences across species.

Internal Mechanisms of Evolution

Driven by genetic material ($DNA$, $RNA$) and proteins affecting morphological, physiological, and physical characteristics.

Scientific Status of Evolution

A well-supported scientific theory comparable to the theory of gravity, based on empirical data.

Fossil Record

Long-term historical evidence of anatomical changes; limitations include incompleteness due to difficulty in fossilizing soft-bodied organisms.

Homologous Structures

Structures that share the same underlying skeletal layout due to common evolutionary ancestry but have different functions (e.g., forelimb layout in various vertebrates).

Embryonic Development Evidence

Remarkable structural similarities in early developmental stages across vertebrates, indicating common ancestry.

Molecular Data in Evolution

Comparison of amino acid sequences and nucleotide sequences reveals evolutionary relationships between species.

Phylogenetics and Evolutionary Trees

Branch lengths quantify evolutionary relationships, indicating shared ancestry among species.

Charles Darwin's Contribution

Naturalist who proposed natural selection as the primary mechanism of evolution through observations on the HMS Beagle.

Alfred Russel Wallace's Contribution

Independently co-discovered the theory of natural selection and co-authored a paper with Darwin.

Gradualism

Proposed by James Hutton, it suggests that species and geological features change slowly over long periods.

Uniformitarianism

Established by Charles Lyell, it posits that geological processes occurring today are similar to those in the past.

Concept of Extinction

Established by Georges Cuvier through the analysis of dinosaur fossils.

Inheritance of Acquired Characteristics

Proposed by Jean-Baptiste Lamarck; incorrect mechanism but recognized that organisms change over time.

Exponential Population Growth

Modeled by Thomas Malthus, highlighting resource limitations as a factor in population dynamics.

Binomial Nomenclature

Developed by Carl Linnaeus for classifying organisms using genus and species names.

Microevolution

Small-scale changes in allele frequencies within populations over generations.

Macroevolution

Large-scale changes leading to speciation and adaptive radiation over extended timeframes.