EEMB 120- Class 1: Introduction to Ecology and Evolutionary Ecology

Foundational vocabulary terms covering the levels of biological organization, ecological research methodologies, and the principles of natural selection and evolution.

Ecology

The scientific study of the interactions of living organisms with their environment, including both biotic and abiotic factors.

Biotic factors

The living components of an environment that interact with an organism.

Abiotic factors

The nonliving components of an environment that interact with an organism.

Individual

A level of biological organization focused on the single organism and its specific physiological or behavioral traits.

Population

A group of individuals of the same species living in the same space at the same time.

Community

An assembly of multiple species interacting within the same space.

Ecosystem

A level of biological organization that includes both the biological community and its physical environment.

Landscape

A level of biological organization characterized by multiple ecosystems.

Biosphere

All areas of the Earth that support life.

Observation

A category of research involving the collection of data in unmanipulated settings, which can be descriptive or used to test hypotheses.

Experiment

A category of research involving the manipulation of variables while holding others constant to test a specific hypothesis.

Natural Experiment

A fortuitous change in the environment that allows researchers to observe the effects of a variable manipulation they did not perform themselves.

Modeling

The use of conceptual descriptions or quantitative mathematical equations to describe or predict patterns in a system.

Trait

A heritable feature of an organism that can be measured on a single individual.

Natural Selection

A process where individuals with adaptive traits have a higher likelihood of surviving and reproducing, leading to changes in populations over time.

Stabilizing Selection

A type of selection where extreme phenotypes have lower rates of reproduction and survival, causing the average phenotype to remain the most common.

Directional Selection

A type of selection where an exceptional phenotype has higher reproduction and survival, causing the population average to shift in a particular direction over time.

Disruptive Selection

A type of selection where average phenotypes have lower survival compared to extremes, leading to a bimodal distribution where the population becomes more phenotypically diverse.

Genetic Drift

A shift in allele and trait distributions in a population due entirely to random chance, which is especially impactful in small populations.

Founder Effect

A form of genetic drift occurring when a subset of an original population forms a new population, with trait diversity dictated by the founding members.

Bottleneck Effect

A form of genetic drift occurring after a random event kills a disproportionate number of individuals, leaving the survivors to dictate the trait diversity of the resulting population.

Historical View of Evolution and Ecology

Evolution was once perceived as static, with species unchanging. The introduction of Darwin's theory of natural selection shifted the view towards dynamic processes of adaptation and change.

Contemporary View of Evolution and Ecology

Evolution and ecology are now seen as interconnected fields, where ecological influences drive evolutionary changes and evolutionary history shapes ecological interactions.

Darwin’s Theory of Natural Selection

A mechanism of evolution based on four key principles: 1) Variation – individuals within a species exhibit variations in traits. 2) Inheritance – traits can be passed from parents to offspring. 3) High rate of population growth – most populations can produce more offspring than the environment can support. 4) Differential survival and reproduction – individuals with advantageous traits are more likely to survive and reproduce.

Examples of Levels of Biological Organization

Biological organization includes different levels: 1) Individual - a single organism, such as a lion. 2) Population - a group of lions living in a pride. 3) Community - all species in a certain area, such as a savannah ecosystem. 4) Ecosystem - includes the community and the abiotic factors, like climate and soil in the savannah.