Bio U1

Morphological species concept

Groups of individuals who are morphologically similar to each other and different from other species.

Biological species concept

Defines a species as a group of organisms capable of reproducing with each other to produce fertile offspring.

Binomial nomenclature

A system created by Linnaeus for giving scientific names to organisms, where all scientific names are italicized or underlined.

Natural selection

The process through which populations of living organisms adapt and change to their environment, resulting in increased survival and reproduction of individuals with favorable traits.

Variation

The difference between characteristics among individuals, which can lead to changes in population dynamics.

Evolution

The change in inheritable characteristics of a population over time.

Genetic variation

Differences in genomes among individuals of the same species, arising from mutations and sexual reproduction.

Carrying capacity

The maximum number of individuals in a population that an environment can sustainably support.

Selectively advantaged trait

Any characteristic that gives an organism a greater chance of surviving and reproducing compared to alternative traits.

Mutations

Errors in DNA replication that introduce new alleles into a population, resulting in genetic variation.

Intrasexual selection

Competition between individuals of one sex (usually males) for mating opportunities with individuals of the opposite sex.

Intersexual selection

The selection by one sex (usually females) for certain traits in individuals of the opposite sex, influencing mate choice.

Homologous structures

Structures that are similar in different species due to shared ancestry but may perform different functions.

Analogous structures

Structures that serve the same function in different species but do not share a common ancestor, resulting from convergent evolution.

Speciation

The formation of new species through evolution, often involving reproductive isolation between populations.

Geographic isolation

A form of reproductive isolation resulting from physical barriers like rivers or mountains that prevent populations from interbreeding.

Darwin’s theory of evolution

Proposes that species change over time through natural selection, with variations among individuals playing a critical role in this process.

Density-dependent factors

Factors that affect population size based on the density of the population in a given area.

Density-independent factors

Abiotic factors affecting population size regardless of the population density.

Molecular phylogeny

Using DNA, RNA, and protein sequences to determine how closely related two species are at a molecular level.

Fossil evidence

The remains or impressions of organisms preserved in rock that provide evidence for evolution.