Predation and Population Dynamics

Predator-prey dynamics are influenced by multiple food sources; prey population fluctuations do not drastically impact predator populations.
Climatic events and diseases can cause abrupt population changes in predators and prey.
Availability of food impacts prey population size; for instance, lemming numbers may decline if berry availability decreases.

Symbiosis: Close, prolonged interactions between different species, where at least one organism benefits.
Mutualism: Both species benefit from the relationship.
- Example: Humans and gut bacteria; humans digest food, bacteria receive a habitat and nutrient source.
Commensalism: One species benefits, while the other is unaffected.
- Example: Barnacles on whales; barnacles gain mobility and feeding opportunities without harming the whale.
Parasitism: One organism benefits at the expense of another.
- Example: Ticks feed on dogs; ticks gain nutrients, while dogs lose blood and may suffer from toxins.
Amensalism: One organism is harmed while the other is unaffected.
- Example: Large trees inhibit the growth of smaller plants by blocking sunlight without being affected.

An organism’s ecological niche encompasses its role, including interactions with biotic and abiotic factors.
Different microorganisms occupy various niches, like gut microbes in humans and those in soil.

Species face extinction risks due to inability to adapt, competition, disease, environmental changes, or reduced food sources.
Genetic diversity is crucial for a population's ability to respond to environmental pressures.

Studying past ecosystems aids in predicting future ecosystem changes.
Analyzing rock layers provides insights into geological events; radiometric dating determines rock age through radioactive decay.

Fossils offer evidence of past life forms, allowing researchers to infer characteristics and adaptations.
A rock's composition and age help date the formation of geological events.
Weathering from climatic events can erode rock, affecting geological analysis.

Ice cores reveal historical climate data; the layers create a timeline from youngest at the surface to oldest at the base.
Biological remains can be preserved in ice, contributing to ecological studies.

Depict species from the past, illustrating their distribution and abundance during specific historical periods.

Habitat Fragmentation: Breaking ecosystems into isolated sections affects breeding and population dynamics.
- Leads to smaller populations with reduced genetic diversity.
- Increased inbreeding risk due to limited breeding options.
- Fragmented habitats complicate food acquisition and expose organisms to dangers during travel between areas.