Module 1 (Introduction to Ecosystems)

Community Ecology

The study of interactions among species within a community, examining how these interactions affect species populations, community structure, and ecosystem dynamics.

Symbiosis

a close and long-term interaction between different species, which can be beneficial, neutral, or harmful.

Biosphere

The global sum of all ecosystems, representing the zone of life on Earth, where many biomes and organisms interact.

Competition

The interaction between organisms or species in which the fitness of one is lowered by the presence of another, often involving the use of limited resources such as food, space, or water.

Competitive Exclusion principle

The principle stating that two species competing for the same limited resource cannot coexist at constant population values; one will outcompete the other.

Resource Partitioning

A process by which competing species exploit the limited resources available in different ways to reduce competition and coexist.

Predation

The interaction where one organism, the predator, hunts and consumes another organism, the prey, which can impact population dynamics and community structure.

Parasitoid

An organism that lives on or in a host organism and ultimately kills the host, often used for biological control of pest populations.

Parasitism

A symbiotic relationship where one organism, the parasite, benefits at the expense of the host, often harming it in the process.

Pathogen

an agent, such as a virus, bacterium, or fungus, that can cause disease in a host organism, often leading to harm or illness.

Herbivory

A type of interaction in which an animal feeds on plants or plant parts, often affecting plant health and ecosystem dynamics.

Mutualism

a symbiotic relationship where both organisms involved benefit from the interaction, often enhancing each other's survival and reproduction.

Photosynthesis

the process by which green plants, algae, and some bacteria convert light energy into chemical energy, using sunlight to transform carbon dioxide and water into glucose and oxygen.

Commensalism

A type of symbiotic relationship where one organism benefits while the other is neither helped nor harmed.

Native Species

Species that are naturally occurring in a particular ecosystem or region, having evolved in that environment over time.

Exotic Species

Species that are introduced to an ecosystem where they are not naturally found, often causing ecological disruption.

Invasive Species

Species that spread rapidly and cause harm to native ecosystems, often outcompeting local species.