The “introns early” hypothesis is the proposal that introns have always been an integral part of the gene.  Genes originated as interrupted structures, and those now without introns have lost them in the course of evolution.

TLS Online TPP Program

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#Unit 10. Ecological Principles

 Brian Walker (1992) proposed the Redundancy hypothesis Species that play the same roles in a community can compensate for each other if some are lost under particular conditions

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#Unit 10. Ecological Principles

Keystone hypothesis

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#Id: 5742

#Unit 10. Ecological Principles

Idiosyncratic hypothesis Community services change as the number of species increases or decreases, but that the direction of change is not predictable

TLS Online TPP Program

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#Unit 10. Ecological Principles

Ecotones - An ecotone is a zone of junction or a transition area between two biomes (diverse ecosystems).

TLS Online TPP Program

#Id: 5744

#Unit 10. Ecological Principles

TLS Online TPP Program

#Id: 5745

#Unit 10. Ecological Principles

Mangrove forests - between marine and terrestrial  ecosystem

Grassland - between forest and desert 

Estuary - between fresh water and salt water

Riverbank or marshland - between dry and wet