enviro quest Flashcards
Genetic Diversity
Variety of genes within a species.
Species Diversity
Variety of species within an ecosystem.
Ecosystem Diversity
Variety of ecosystems in a region (like terrestrial or aquatic ecosystems).
Island Biogeography
Study of species distribution on islands.
Larger Islands
Higher immigration rates (bigger target for species).
Lower extinction rates (more space supports bigger populations).
Specialist Species
Evolve on islands due to limited resources. Vulnerable to invasive species (generalists).
Distance Effect
Farther islands from the continent have fewer species due to difficulty in colonization.
Habitat Fragmentation
Fragmentation happens when parts of a habitat are destroyed, leaving behind smaller unconnected areas. This theory also applies to isolated habitats on land.
Habitat
A place where an organism lives.
Niche
The role an organism plays in its environment.
Example: Beavers eat wood, build dams, and create habitats for other species.
Generalists
Have broad niches and do well in changing habitats.
Specialists
Have narrow niches and thrive in stable habitats.
Evolution
Change in gene frequencies in a population over time.
Artificial Selection:
Traits are chosen by humans.
Natural Selection
Traits chosen by the environment, favoring survival traits.
Fitness
Ability to survive and reproduce.
Adaptations
Traits that improve fitness.
Mutations
Genetic changes.
Genetic Drift
Changes in a population due to chance.
Bottleneck Effect
Reduction in population size and genetic diversity.
Founder Effect
New populations start with a small number of individuals, limiting genetic diversity.
Succession
Ecosystem changes over time.
Pioneer Species
First to colonize and prepare the environment for others.
Primary Succession
Starts on new soil (e.g., volcanic rock).
Secondary Succession
Follows a disruption (e.g., fire or flood).
Climax Community
Stable, mature community that develops over time
Keystone Species
Crucial for ecosystem balance; their removal causes drastic community changes.
Example: Seastars control mussel populations. Without seastars, mussels overtake the ecosystem, reducing diversity.
Indicator Species
Species whose presence, absence, or condition indicates ecosystem health (e.g., thriving or unhealthy).
Fossils
Imprints of organisms in stone.
Fossil Record
Collection of fossils worldwide, which provides evidence for evolutionary changes over time.
