Animal Ecology (Ekologi Hewan) 3 SKS / 4314-2-1962

Ecology The science of the study of the relationships between living things and their environment The environment could be: Biotic = other species Nonbiological (abiotic) = physical, chemical, geographical, geological factors

The study of the distribution and abundance of organisms. Ecology The study of the distribution and abundance of organisms. Charles Elton, Animal Ecology 1927

Ecology The scientific study of the relationships between organisms and their environments. E. Haeckel, 1865

Chapin, Mooney and Matson, 2002 Ecology The study of the flows of energy and materials between abiotic and biotic components of ecosystems. Chapin, Mooney and Matson, 2002

The study of the distribution and abundance of organisms, Ecology is The study of the distribution and abundance of organisms, AND the flows of energy and materials between abiotic and biotic components of ecosystems.

Ecosystem Ecosystem = community (all biotic) & physical environment (all abiotic)

Ecological sciences General ecology Animal ecology, plant ecology, microbial ecology Environmental science Environmental protection and management Hydrobiology (water ecosystems) Limnology (freshwater ecosystems) Environmental geology and geography

Applications of Animal Ecology Medical ecology Preventive medicine (hygiene) Toxicology Medical parasitology Medical microbiology Veteriner

Basic ecological terms

Population A group of individuals of the same species living in the same area or interbreeding and sharing genetic information. Population of species A Population of species B

Ecosystem Biological community and nonbiological factors Ecosystem = community (all biotic) & physical environment (all abiotic) Biological community and nonbiological factors It must include: An autotroph A decomposer A source of energy All the chemical elements required by the autotroph and the decomposer

Ecosystem Abiotic factors Community Population of species A Population of species B Community Population of species C

Habitat Habitat = any part of the Earth where a species can live, temporarily or permanently = organism’s physical surroundings = where an organism lives

Ecological Niche Ecological Niche = functional role of a species in the community, including habitat, activities & relationships = what an organism does, its occupation

Food web (trophic „chain“) Solar energy Secodary consumers (carnivores) Primary consumers (herbivores) Producers (green plants, algae, autotrophic bacteria) Decay of organic matter Release of inorganic nutrients Decomposers (heterotrophic bacteria, fungi)

Main Structural Components of an Ecosystem Abiotic chemicals (carbon dioxide, oxygen, nitrogen, minerals) Heat Heat Solar energy Heat Decomposers bacteria, fungi) Producers (plants) Consumers (herbivores, carnivores) Heat Heat 17

Energy flow within food web Biomass of secondary consumers Loss of energy Loss of energy Biomass of primary consumers Biomass of producers

What is productivity? Productivity: growth rate of all living things Primary productivity: growth rate of producers Solar energy converted to organic matter (biomass) Stored in living organisms All organisms depend on primary producers for their energy supply Usually measured as grams of carbon per square meter Primary production is consumed, converted to detritus, or accumulated in biomass Ecologists like to talk about the productivity of ecosystems, that is, the amount of solar energy that is stored in living organisms Some ecosystems are more efficient at storing energy than others Because primary producers make oxygen and consume carbon dioxide, we can estimate primary production by measuring the amount of oxygen that is produced (or carbon dioxide that is consumed) in a bottle or in a section of the river. Alternatively, we can add a little14-carbon, which is radioactive, to a bottle of water, and measure the amount of radioactivity that is picked up by phytoplankton. Production of bacteria is also estimated by measuring the uptake of radioactive nucleic acids or amino acids. 19

What controls productivity? “Limiting factors” - Too much or too little of any abiotic factor can limit or prevent growth of a population Predators: grazers Every part of the food web will have different controls What could be a limiting factor in the Limboto lake?

Interspecific relations Species A Species B Neutralism No relation, neither effects the other Commensalism + Protocooperation Free relation Mutualism („symbiosis“) Closed relation Allelopathy (inhibition) 0 (+?) – Species A produces compounds harmful for species B. „antibiosis“ Parasitism Predation Competition

Individual assignment on Interspecific relations! See you next week! Individual assignment on Interspecific relations!