Evolutionary Biology

Vocabulary flashcards covering key terms, geological eras, theories on the origin of life, and influential scientists in evolutionary biology based on lecture notes.

Evolution

A change in populations across generations, occurring at the population level rather than within a single individual during its lifetime.

Origin of Life

The study of how nonliving matter became living, as distinguished from evolution which studies how existing living populations change.

Hadean Eon

The very early period of Earth's history characterized by extreme heat, molten material, heavy bombardment from space, no ozone layer, and an absence of free oxygen and initial oceans.

Reducing Atmosphere

An early Earth atmosphere with little or no free oxygen, which created chemical conditions that favored the formation of organic molecules.

Abiotic Synthesis

The formation of organic building blocks—such as amino acids, nucleotides, sugars, lipids, and ATP—without the involvement of living organisms.

Protocells

Structures formed from lipid bilayers that create an internal watery cavity, concentrating chemicals and separating them from the external environment.

RNA World

The hypothesis that early hereditary material was RNA, which could abiotically form, store genetic information, and exhibit catalytic, enzyme-like properties.

Miller-Urey Experiment

An experiment using water, gases, and electrical sparks simulating early Earth conditions that successfully produced organic molecules like amino acids and nucleotides abiotically.

Proximity Problem

The challenge where dilute organic molecules in a large body of water are spread too far apart to form polymers; solved on early Earth by positively charged clay attracting negative molecules.

Viroids

Very small pieces of RNA lacking a protective protein coat that require a host to replicate and are not considered alive.

Panspermia

The hypothesis that life or its organic building blocks originated somewhere other than Earth and were transported here.

Stromatolites

Fossilized mats associated with cyanobacteria found in the Archean eon.

Cambrian Explosion

A major diversification event early in the Paleozoic era during which many major animal groups appeared.

Mesozoic Era

The geological era known as the Age of Reptiles, during which dinosaurs were prominent, early mammals appeared, and which ended in a major mass extinction.

Cenozoic Era

The geological era known as the Age of Mammals, during which mammals became especially dominant and humans appeared.

Extinction

The complete disappearance of a species.

Linnaeus

The scientist whose main work focused on the classification of organisms.

Georges Cuvier

A scientist who demonstrated through fossils and comparative anatomy that extinction is real and who proposed catastrophism.

James Hutton

A geologist who advocated gradualism, demonstrating that Earth changes through slow, continuous processes and is extremely old.

Charles Lyell

A geologist who developed uniformitarianism, proposing that the same geological processes occurring today operated in the past.

Jean-Baptiste Lamarck

A scientist who formulated the first complete theory of evolution, proposing that acquired traits developed during an organism's lifetime could be inherited by offspring.

Thomas Malthus

An economist who proposed that population growth outpaces limited resources, creating a struggle for existence and competition.

Adam Smith

An economist associated with the concept of competition and the invisible hand.

Charles Darwin

A naturalist who studied organisms on the HMS Beagle and developed the theory of evolution by natural selection, common descent, and transmutation.

Alfred Russel Wallace

A naturalist who independently developed the theory of natural selection while studying species in the Malay Archipelago.

Wallace's Line

A geographic boundary in the Malay Archipelago reflecting historic isolation and marking major differences in species distributions between nearby islands.

Natural Selection

An evolutionary mechanism requiring variation, differential reproductive success, and heritability, where advantageous traits become more common in a population over time.

Peter and Rosemary Grant

Researchers who documented natural selection in action by studying changes in beak characteristics of finches on Daphne Major during environmental droughts.

Gregor Mendel

The scientist recognized for discovering the principles of heredity.

Rosalind Franklin

The scientist who generated evidence that was crucial to understanding the structure of DNA.