Competition and patterns of distribution

Competition & pattern distribution Members of each species evolve adaptations to living in certain conditions and distribute themselves within their physiological tolerance levels.

Competition & pattern distribution Members of each species evolve adaptations to living in certain conditions and distribute themselves within their physiological tolerance levels. The can reduce interspecific comp and allows co-existence.

Stratification A distinct vertical pattern seen in the species distribution of a community – typical in plant communities.

Stratification A distinct vertical pattern seen in the species distribution of a community – typical in plant communities. Large trees form the canopy are sun plants and can utilise high light intensities.

Stratification A distinct vertical pattern seen in the species distribution of a community – typical in plant communities. Large trees form the canopy are sun plants and can utilise high light intensities. Smaller trees and shrubs are shade plants and utilise lower light intensities.

Zonation A distinct horizontal pattern seen in species distribution across a community.

Zonation A distinct horizontal pattern seen in species distribution across a community. The species best adapted = dominant species.

Zonation A distinct horizontal pattern seen in species distribution across a community. The species best adapted = dominant species. Once enviro conditions exceed limits of that species, another species forms the next zone.

Succession A distinct pattern over time seen in species distribution of a community.

Succession A distinct pattern over time seen in species distribution of a community. When a new habitat becomes available (Eg – after flooding) it may take years, before a community can re-establish itself.

Succession A distinct pattern over time seen in species distribution of a community. When a new habitat becomes available (Eg – after flooding) it may take years, before a community can re-establish itself. Primary succession – coastal habitats (Eg – sand dunes), mangroves and bare rock. The environment is so unfavourable only a few pioneer species can survive.

Succession A distinct pattern over time seen in species distribution of a community. When a new habitat becomes available (Eg – after flooding) it may take years, before a community can re-establish itself. Primary succession – coastal habitats (Eg – sand dunes), mangroves and bare rock. The environment is so unfavourable only a few pioneer species can survive. EG – on bare rock only lichen can survive due to lack of water. They hook into cracks and are used for other plants to establish themselves – like moss. Moss builds up and encourages other small plants to grow as well. https://www.youtube.com/watch?v=jZKIHe2LDP8

Succession Secondary succession – occurs when fertile soil exists from the start and the growth is much more rapid than primary.

Succession Secondary succession – occurs when fertile soil exists from the start and the growth is much more rapid than primary. EG – re-growth of forest after a fire.

Contest or interference competition Occurs when some individuals of one species actively prevent individuals of another species obtaining a resource.

Contest or interference competition Occurs when some individuals of one species actively prevent individuals of another species obtaining a resource. Eg – a group of hyenas chasing a lion away from its kill.

Contest or interference competition Occurs when some individuals of one species actively prevent individuals of another species obtaining a resource. Eg – a group of hyenas chasing a lion away from its kill. Also occurs within many species resulting in social hierarchy and territoriality

Antibiosis Is a relationship between numbers of two difference species in which one species releases a substance that inhibits the growth or kills another species.

Antibiosis Is a relationship between numbers of two difference species in which one species releases a substance that inhibits the growth or kills another species. Eg – Fungi and bacteria. The fungi produces a chemical which stops the growth of bacteria (viola! Antibiotic)

Allelopathy Where a plant species (+) produces a chemical that stops the growth or is toxic to other plants, soil organisms, or herbivores (-)

Allelopathy Where a plant species (+) produces a chemical that stops the growth or is toxic to other plants, soil organisms, or herbivores (-) EG – The roots of some gum trees (Eucalyptus) produce chemicals that stop the growth of other plant species around them.