201ch22 pdf

Descent with Modification

A principle that states all organisms are related through descent from a common ancestor.

Natural Selection

The process by which certain traits become more common in a population due to their advantage in survival and reproduction.

Zoology

The scientific study of animals.

Charles Darwin

The author of 'On the Origin of Species' and the proponent of the theory of natural selection.

The Origin of Species

A landmark book by Charles Darwin that introduced the theory of evolution through natural selection.

Lamarckism

The belief that an organism can pass on characteristics acquired during its lifetime to its offspring.

Catastrophism

The theory that the Earth has been affected by sudden, short-lived, and catastrophic events.

Uniformitarianism

The geological doctrine that the same processes observed in the present have always occurred.

Microevolution

Minor evolutionary changes that occur within a species.

Biogeography

The study of the geographic distribution of living organisms.

Fossil Record

The history of life as documented by fossils.

Comparative Anatomy

The study of similarities and differences in the anatomy of different species.

Comparative Embryology

The study of the embryonic development of different organisms to understand evolutionary relationships.

Malthusian Theory

The theory that population grows exponentially while food production grows arithmetically, leading to competition.

Gene Flow

The transfer of genetic material between populations.

Genetic Drift

Random changes in allele frequencies in a population.

Homologous Structures

Anatomical features in different species that share a common ancestry.

Analogous Structures

Body parts in different species that serve similar functions but differ in structure and origin.

Vestigial Structures

Body parts that have lost their original function through evolution.

Hox Genes

Genes that control the development of body structures in animals.

Evolutionary Theory

The body of knowledge explaining the processes by which species change and adapt over time.

Adaptive Radiation

The process by which a single ancestor species rapidly diversifies to adapt to a variety of environments.

Speciation

The formation of new and distinct species in the course of evolution.

Phylogenetic Tree

A branching diagram showing the evolutionary relationships among various biological species.

Extinction

The dying out of a species.

Transitional Fossils

Fossils that show intermediate states between an ancestral form and that of its descendants.

Cyanobacteria

Photosynthetic bacteria that are among the earliest forms of life on Earth.

Homology

The existence of shared ancestry between a pair of structures, or genes, in different taxa.

Pangaea

A supercontinent that existed during the late Paleozoic and early Mesozoic eras.

Continental Drift

The gradual movement of continents over geological time.

Mutation

A change in the DNA sequence that can lead to variation within a population.

Stabilizing Selection

Natural selection that favors average individuals in a population.

Directional Selection

Natural selection that favors one extreme phenotype over others.

Disruptive Selection

Natural selection that favors extreme phenotypes over intermediate ones.

Selection Pressure

Environmental factors that influence which individuals survive and reproduce.

Phenotype

The expression of an organism's genetic traits.

Genotype

The genetic makeup of an organism.

Species

A group of organisms that can interbreed and produce fertile offspring.

Variability

The tendency of certain traits to vary within a population.

Survival of the Fittest

A phrase associated with Darwin that describes the mechanism of natural selection.

Morphological Characteristics

The form and structure of organisms that can show evolutionary relationships.

Radiometric Dating

A method used to determine the age of rocks and fossils based on the decay of radioactive isotopes.

Species Richness

The number of different species represented in an ecological community.

Ecological Niche

The role and position a species has in its environment.

Biometrics

The measurement and statistical analysis of people's unique physical and behavioral characteristics.

Skin Color Variation

Differences in skin color among populations caused by adaptations to environmental factors.

Cultural Evolution

The changes in human culture over time, influenced by learning, copying, and social transmission.

Genomic Sequencing

The process of determining the complete DNA sequence of an organism's genome.