Descent with Modification, A Darwinian View of Life (Chapter 22)

Vocabulary flashcards covering key Darwinian evolution concepts from Chapter 22.

Descent with modification

Darwin's idea that lineages split and accumulate changes over time, producing new species from a common ancestor.

Evolution

Change in the genetic makeup of a population across generations.

Natural selection

Process by which heritable traits that enhance survival/reproduction become more common in a population over generations.

Adaptation

A heritable trait that increases an organism's fitness in its environment.

Unity of life

All organisms share a common ancestry, leading to similarities across life.

Diversity of life

Many distinct forms arising through branching lineages and adaptation.

Fossil

Preserved remains or traces of organisms from the past.

Strata

Layers of sedimentary rock in which fossils are found.

Paleontology

The science of studying fossils and ancient life.

Catastrophism

Idea that boundaries between strata were formed by sudden, catastrophic events.

Uniformitarianism

Geological change results from slow, ongoing processes acting today.

Gradualism

Large changes arise from the accumulation of small changes over long times.

Inheritance of acquired characteristics

Lamarck's idea that traits developed during life can be passed to offspring.

Use and disuse

Lamarckian mechanism where organs grow with use and shrink with disuse.

Binomial nomenclature

Two-part format for naming species (genus and species), e.g., Homo sapiens.

Taxonomy

Science of classifying organisms.

Linnaeus

Founder of taxonomy; devised binomial nomenclature and classification.

Aristotle

Greek philosopher who proposed scala naturae and fixed species.

Scala naturae

Great chain of being; a linear scale of increasing complexity with fixed species.

Beagle voyage

Darwin's five-year voyage on HMS Beagle, collecting specimens and making observations.

Galápagos Islands

Islands studied by Darwin that influenced ideas about speciation and adaptation.

Speciation

Formation of new species through reproductive isolation.

Alfred Russel Wallace

Naturalist who independently conceived natural selection; prompted Darwin to publish.

Overproduction

Populations produce more offspring than resources can support.

Competition for resources

Limited resources lead to differential survival and reproduction.

Thomas Malthus

Economist whose ideas about population growth influenced Darwin.

Artificial selection

Humans breed individuals with desired traits to shape populations.

Mutation

Change in a DNA sequence; source of new genetic variation.

Genetic variation

Differences in DNA among individuals within a population.

Population

Interbreeding group of individuals of the same species in a given area.

Fitness

Reproductive success; the contribution of an individual’s genes to future generations.

Phylogenetic tree

Diagram showing evolutionary relationships based on common ancestry.

Branch point

Node where a lineage splits into two or more lineages from a common ancestor.

Homology

Similarity due to shared ancestry.

Vestigial structures

Remnants of features that served a function in ancestors but are reduced or unused.

Comparative embryology

Comparison of embryo development across species to reveal shared features.

Convergent evolution

Independent evolution of similar traits in different lineages due to similar environments.

Analogous structures

Structures with similar function but different evolutionary origins.

Biogeography

Study of the geographic distribution of species.

Endemic species

Species native to and restricted to a particular geographic area.