KA Biology Unit 8

Macroevolution

Large-scale evolution occurring over extended time periods, resulting in the divergence of species from common ancestors.

Homologous structures

Anatomical features shared by different species due to inheritance from a common ancestor.

Analogous structures

Features that are similar in function and appearance but evolved independently due to similar selective pressures; not due to common ancestry.

Molecular biology

The study of the molecular basis of biological activity, providing evidence for shared ancestry through DNA and protein similarities.

Biogeography

The study of the geographical distribution of organisms, which helps to understand evolutionary relationships.

Fossils

Preserved remains of organisms or traces from the past, used as evidence of long-term evolutionary changes.

Microevolution

Small-scale evolutionary changes that occur within populations, observable over shorter timescales.

Phylogenetic tree

A diagram that illustrates the evolutionary relationships among species, based on common ancestry.

Vestigial structures

Reduced or non-functional features that have little or no present use, yet provide insights into an organism's ancestry.

Convergent evolution

The independent evolution of similar traits in different species due to adaptation to similar environments.

Common ancestor

The most recent species from which two or more species have evolved.

Radiometric dating

A method used to date materials based on the decay of radioactive isotopes, often used for dating fossils.

Extinction

The end of an organism or group of organisms, resulting in the complete disappearance from Earth.

Mass extinction

An event where a large percentage of species go extinct in a short period, often due to catastrophic events.

K-Pg event

A mass extinction event occurring around 66 million years ago, leading to the extinction of non-avian dinosaurs.

Outgroup

A species or group that is distantly related to the group of interest, used to infer ancestral traits.

Derived traits

Traits that are different from those of the ancestor of a group, often used in constructing phylogenetic trees.

Ancestral traits

Features that were present in the common ancestor of a group.

Polytomy

A branch point in a phylogenetic tree where three or more descendant groups emerge, indicating unresolved relationships.

Descent with modification

Darwin's theory that species evolve over time through adaptations and changes passed down from common ancestors.

Evolutionary relationships

The connections between species based on shared ancestry and evolutionary history.

Nucleotide sequences

The specific order of nucleotides in a DNA or RNA strand, used to analyze evolutionary relationships.

Homologous genes

Genes in different species that share a common ancestry, often used to assess genetic relatedness.

Gene expression

The process by which information from a gene is used to synthesize functional gene products (like proteins).

Morphological features

Physical characteristics of organisms used in taxonomy and phylogenetic analysis.

Cladistics

A method of classifying species based on common ancestry and branching patterns.

Adaptive radiation

The rapid evolution of diversely adapted species from a common ancestor in response to environmental opportunities.

Fossil record

The cumulative collection of fossils that provide evidence of past life and evolutionary pathways.

Common descent

The principle that all living organisms share a common ancestor at some point in their evolutionary history.

Phylogenetics

The study of evolutionary relationships among biological entities, often using genetic data.

Herbivores

Organisms that primarily eat plants, which have evolved various adaptations for consuming plant materials.

Carnivores

Organisms that primarily consume meat, often having adaptations for hunting and digesting flesh.

Ecosystem

A biological community of interacting organisms and their physical environment.

Species diversity

The variety of species within a given ecosystem or community.

Evolutionary biology

A branch of biology that studies the processes that produced the diversity of life on Earth, primarily through evolution.

Genetic drift

Random changes in allele frequencies in a population, which can lead to evolution over time.

Natural selection

A process by which organisms better adapted to their environment tend to survive and produce more offspring.

Mutation

A change in the DNA sequence of an organism's genome, introducing new genetic variation.

Gene flow

Transfer of genetic variation from one population to another, contributing to genetic diversity.

Biological taxonomy

The science of naming, defining and classifying organisms into groups based on shared characteristics.

Evolutionary history

The sequence of events and changes through which species have developed over time.

Anatomical features

Physical structures in organisms that are used to determine evolutionary relationships.

Species concept

A definition or model used to categorize and characterize species.

Lineage

A series of species that are connected through a common ancestor, representing evolutionary history.

Adaptive traits

Characteristics that enhance an organism's ability to survive and reproduce in its environment.

Sister taxa

Groups of organisms that share an immediate common ancestor in a phylogenetic tree.

Cladogram

A diagram that depicts the hypothetical evolution of species through branches and nodes, based on shared traits.

Synapomorphies

Shared derived characteristics that can be used to establish evolutionary relationships among species.

Phenotype

The observable characteristics or traits of an organism, influenced by genetics and environment.

Genotype

The genetic constitution of an individual organism, comprising its alleles.

Morphological classification

Organizing species based on their physical characteristics.

Taxonomic hierarchy

A system of organizing biological diversity from general to specific: domain, kingdom, phylum, class, order, family, genus, species.

Secondary extinction

The extinction of species that is caused by the primary extinction of other species within an ecosystem.

Conservation biology

A discipline focused on the study and preservation of biodiversity and endangered species.

Interspecies competition

Competition for resources between different species within an ecosystem.

Phylogeography

The study of the historical processes that may be responsible for the contemporary geographic distributions of individuals.

Biodiversity hotspot

A biogeographic region with a significant reservoir of biodiversity that is threatened by human activities.

Extinction risk

The likelihood of a species becoming extinct in the near future.

Ecological niche

The role or function of an organism or species within an ecosystem.

Paleoecology

The study of ecosystems and environmental conditions in past geological ages.

Radiation pattern

The branching pattern of species that emerges due to evolutionary processes.

Gene sequencing

The process of determining the sequence of nucleotides in a DNA molecule, used for analyzing genetic relationships.

Population genetics

The study of genetic variation within and between populations, essential for understanding evolution.

Environmental adaptation

The process through which a species becomes better suited to its environment over generations.

Ecological succession

The process of change in the species structure of an ecological community over time.

Speciation

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

Phylogenomic analysis

The analysis of genomic data to understand evolutionary relationships.

Homoplasy

A similarity in traits that is not due to common ancestry, often resulting from convergent evolution.

Cretaceous Period

The last period of the Mesozoic Era, known for the dominance of dinosaurs and the mass extinction at its end.

Paleogene Period

The time following the Cretaceous, marked by the rise of mammals after the extinction of dinosaurs.

Plate tectonics

The theory explaining the movement of the Earth's lithosphere plates, impacting biogeography and evolution.

Mutualism

A symbiotic relationship where both species benefit from the interaction.

Commensalism

A symbiotic relationship where one species benefits and the other is neither helped nor harmed.

Parasitism

A symbiotic relationship where one species benefits at the expense of the other.

Biological revolution

Rapid evolutionary changes in species due to significant environmental shifts or events.

Niche partitioning

The process by which competing species utilize different resources to coexist.

Ecosystem service

The benefits that humans derive from ecosystems, such as pollination, clean water, and climate regulation.

Climate change

Long-term alterations in temperature and typical weather patterns in a place, impacting species evolution.

Anthropogenic impact

Human activities that affect ecosystems and contribute to extinction pressures on species.

Conservation status

An assessment of the risk of extinction for a species, based on population trends and habitat conditions.

Genetic homogenization

The process by which genetic diversity of a species decreases, often due to human influence and habitat change.

Sustainable development

Development that meets present needs without compromising future generations' ability to meet their own needs.

Species reintroduction

The process of returning a species to its native habitat after it has been extirpated.

Biodiversity conservation

Efforts to protect and preserve the diversity of life on Earth, particularly endangered species.

Endangered species

A species at risk of extinction due to habitat loss, predation, pollution, and other factors.

Invasive species

Non-native species that, when introduced to a new environment, can disrupt local ecosystems and outcompete native species.

Climate resilience

The ability of a species or ecosystem to adapt to changing climatic conditions.

Ecosystem integrity

The state of an ecosystem where its composition, structure, and function are intact and resilient.

Nutrient cycling

The movement and exchange of organic and inorganic matter back into the production of living matter within ecosystems.

Species interaction

The various ways in which species within an ecosystem interact, including predation, competition, and symbiosis.

Evolutionary pressure

Environmental factors that influence the survival and reproduction of organisms, driving natural selection.

Historical biogeography

The study of the distributions of species over time, considering geological and climatic changes.

Experimental evolution

The study of evolutionary processes in a controlled environment, allowing researchers to observe real-time evolution.

Phylogenetic perspective

Understanding evolutionary relationships and patterns of divergence among species based on phylogenetic data.

Community ecology

The study of interactions between species and how these interactions shape community structure.

Population dynamics

The study of how populations change over time due to births, deaths, immigration, and emigration.

Microbial evolution

The evolutionary changes that occur in microorganisms, which can influence larger ecological systems.

Adaptive response

Changes in an organism that enhance its survival and reproduction in response to environmental challenges.

Earth's biodiversity

The variety of life forms that have developed on Earth over time through evolutionary processes.

Evolutionary synthesis

An integrated understanding of evolution that combines genetics with natural selection and paleontology.