BIOL 120: Evolution, Taxonomy, and Speciation Key Concepts

taxonomy

The science of naming and classifying organisms.

binomial nomenclature

A formal system of naming species of living things by giving each a name composed of two parts.

classification

The arrangement of organisms into categories based on shared characteristics.

global biodiversity

The variety of life on Earth, including the variety of species, genetic diversity, and ecosystem diversity.

scientific hierarchical classification system

A system that organizes living organisms into a hierarchy of categories: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

3 Domains

Bacteria, Archaea, and Eukarya.

Prokaryotic groups

Include Bacteria and Archaea.

4 Kingdoms of Eukarya

Protista, Fungi, Plantae, and Animalia.

Archaea

Single-celled microorganisms that are prokaryotes and distinct from bacteria.

Bacteria

Single-celled prokaryotic organisms that can be found in various environments.

Physical & Genetic classification

Physical classification is based on observable traits, while genetic classification is based on DNA and genetic similarities.

evolution

The process by which different kinds of living organisms develop and diversify from earlier forms.

fossil record

The history of life as documented by fossils, providing evidence of evolution.

transitional organisms

Fossils or organisms that exhibit traits common to both an ancestral group and its derived descendant group.

radiometric dating

A method used to date materials by comparing the abundance of a radioactive isotope to its decay products.

stratigraphy

The study of rock layers (strata) and layering (stratification).

comparative anatomy

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

homologous structures

Anatomical features in different species that share a common ancestry.

comparative embryology

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

evidence for a common ancestor

Data from various fields such as genetics, fossil records, and comparative anatomy that support the idea of a shared ancestor among species.

biogeography

The study of the distribution of species and ecosystems in geographic space and through geological time.

molecular biology

The branch of biology that deals with the structure and function of the macromolecules essential to life.

convergence

The process where organisms not closely related independently evolve similar traits.

microevolution

Small-scale evolutionary changes that occur within a species.

macroevolution

Large-scale evolutionary changes that occur over long periods.

allele frequencies

The relative frequency of an allele at a genetic locus in a population.

gene pool

The complete set of genetic information within a population.

categories of alleles

Dominant, recessive, and co-dominant alleles, with examples of each.

variability

The tendency of individual variation in a population.

heritability

The proportion of observed variation in a trait that can be attributed to inherited genetic factors.

limiting factors

Environmental conditions that limit the growth, abundance, or distribution of an organism or a population.

speciation

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

fitness in evolution

The ability of an organism to survive and reproduce in its environment.

artificial selection vs. natural selection

Artificial selection is the intentional breeding for certain traits, while natural selection is the process where organisms better adapted to their environment tend to survive and produce more offspring.

biological species concept

A definition of species based on the ability to interbreed and produce viable offspring.

viable & fertile

Viable refers to the ability to live and develop, while fertile refers to the ability to produce offspring.

natural and artificial selection

Natural selection occurs without human intervention, while artificial selection is guided by human choice.

conditions for speciation

Factors such as geographic isolation, reproductive isolation, and genetic divergence that can lead to the formation of new species.

separation of populations

Important for speciation as it reduces gene flow between groups.

genetic divergence

The process in which two or more populations of an ancestral species accumulate independent genetic changes.

reproductive isolation

A collection of evolutionary mechanisms that prevent species from mating.

temporal isolation

A form of reproductive isolation where species breed at different times.

behavioral isolation

A form of reproductive isolation where differences in mating behaviors prevent species from interbreeding.

mechanical isolation

A form of reproductive isolation where physical differences prevent mating.

gamete isolation

A form of reproductive isolation where sperm and egg are incompatible.

hybrid inviability

A condition where hybrid offspring fail to develop properly and die before reaching reproductive maturity.

hybrid infertility

A condition where hybrid offspring are sterile and cannot reproduce.

hybrid species

A species that is a result of the hybridization of two different species.

natural vs. artificial hybrids

Natural hybrids occur in nature, while artificial hybrids are created through human intervention.

reasons for natural hybrids

Factors such as overlapping habitats and mating behaviors that lead to hybridization in nature.

reasons for artificial hybrids

Intentional breeding for desired traits or characteristics by humans.

Protista

A kingdom of eukaryotic organisms that are not animals, plants, or fungi. They are a diverse group, often single-celled, and include algae, protozoa, and slime molds.

Fungi

A kingdom of eukaryotic organisms that include microorganisms such as yeasts, molds, and mushrooms. They are heterotrophic, obtaining nutrients by absorbing dissolved molecules from their environment.

Plantae

A kingdom of multicellular eukaryotic organisms that perform photosynthesis, producing their own food. This kingdom includes trees, flowers, grasses, and other forms of plant life.

Animalia

A kingdom of multicellular, eukaryotic organisms that are heterotrophic, meaning they consume other organisms for food. This kingdom includes all animals, from insects to mammals.

artificial selection

The intentional breeding for certain traits.

natural selection

The process where organisms better adapted to their environment tend to survive and produce more offspring.