lecture 6 - paleoecology Flashcards
(12 cards)
What is paleoecology?
The study of interactions between ancient organisms and their environments, including autecology (individuals) and synecology (communities).
Contrast autecology and synecology.
Autecology: Focuses on individual organisms and their environmental adaptations.
Synecology: Examines entire communities and their ecological relationships.
List the levels of ecological hierarchy from largest to smallest.
Biosphere (global life zone).
Ecosystem (e.g., marine/terrestrial systems).
Community (local species associations).
Habitat (physical living space).
Niche (organism’s role/adaptations).
Define benthic and pelagic zones.
Benthic refers to the bottom of a body of water, while pelagic refers to the open water, away from the shore and bottom
Classify benthic organisms by substrate interaction.
Infaunal (burrowers).
Epifaunal (surface dwellers).
Sessile (immobile).
Vagile (mobile).
What are the key components of a food web?
Producers (photosynthesizers).
Consumers (herbivores, carnivores).
Decomposers (recycle nutrients).
Scavengers/Parasites (secondary roles).
Name five critical environmental factors for organisms.
Temperature (metabolism/growth).
Oxygen (respiration).
Salinity (osmotic balance).
Depth/Light (photic zone limits).
Substrate (habitat suitability).
Describe oxygen distribution in marine environments.
Aerobic (surface, >1.0 ml/l).
Dysaerobic (mid-depth, 0.1–1.0 ml/l).
Anaerobic (deep/stagnant, <0.1 ml/l).
Differentiate euryhaline and stenohaline organisms.
Euryhaline: Tolerate wide salinity ranges (e.g., oysters).
Stenohaline: Require stable salinity (e.g., corals).
Why is the photic zone ecologically critical?
Sunlight penetration (≤200 m) supports photosynthesis.
High biodiversity (autotrophs, herbivores, carnivores).
How does temperature influence marine life?
Higher temps: Faster growth, smaller body size (tropical species).
Stability: Marine temps are buffered by water’s heat capacity.
What happens below the CCD? (carbonate compensation depth)
Calcite dissolves; only siliceous oozes accumulate (depth ~3000–4000 m).
