Human Ecology Exam 2: Key Concepts

Populations Decline and Extinction

Multiple environmental and social pressures can combine. Example: Greenland Vikings

Sustainable Harvesting

Extraction can exceed population replacement. Example: Atlantic Cod

Population Regulation

managed hunting can help control population impacts. Example: White-tailed deer

Competition and Indirect Effects

One invasive species can influence multiple organisms and human health. Example: Amur Honeysuckle

Ecosystem Services

Humans depend on organism for benefits beyond direct consumption. Example: Pollination

Resource Depletion

Groundwater use can exceed natural recharge Example: Ogallala Aquifer

Nutrient Enrichment

Excess nutrients can lead to oxygen-depleted dead zones. Example: Eutrophication

Sustainability

Individual incentives can collectively damage shared resources

Seasonal Mismatch

Environmental change can disrupt biological timing. Example: Mountain hares

Habitat Isolation

Species with limited suitable habitat can be vulnerable to extinction. Example: Appalachian sky islands

Predation and Community Dynamics

Changes to one microbial population can alter an ecosystem. Example: Gut Phages

Mutualism and Ecosystem Function

Microbes can provide protective benefits to humans. Example: Skin Bacteria