BIOL 1020 and BIOL 1021 - Lecture 20
- Community Ecology-2
Assigned Readings in Textbook:
Chapter 47 (section 47.4) – Ecological Communities (pages 1031 to 1036)
Use the following wireframe outline to make notes on the content presented in Lecture 20
Refer to Chapter 47 in your textbook and the Chapter 47 resources on LaunchPad to supplement
your notes and aid in studying this material
Community Ecology:
1. What are some special roles for species in an ecological community?
Role Definition
A species which is most numerous and forms the bulk of
Dominant Species biomass may be considered the dominant species
A species that exerts strong control of a community despite not
being the most abundant species in its community
Exerts a greater impact than expected from its abundance
Keystone Species
Removal of a keystone species has substantial ripple effects
– alters the food chain
A species that can change an ecosystem through its activities
Engineering Species Make new habitats for other species
But also destroy habitats affecting species living there
A species that spreads widely and rapidly becoming dominant
in a community and changing the community’s normal
functioning
Invasive Species • Many invasive species are non-native, introduced from
other areas - have no natural controls (e.g. predation,
disease, competition) in invaded area
1
- Community Ecology-2
Assigned Readings in Textbook:
Chapter 47 (section 47.4) – Ecological Communities (pages 1031 to 1036)
Use the following wireframe outline to make notes on the content presented in Lecture 20
Refer to Chapter 47 in your textbook and the Chapter 47 resources on LaunchPad to supplement
your notes and aid in studying this material
Community Ecology:
1. What are some special roles for species in an ecological community?
Role Definition
A species which is most numerous and forms the bulk of
Dominant Species biomass may be considered the dominant species
A species that exerts strong control of a community despite not
being the most abundant species in its community
Exerts a greater impact than expected from its abundance
Keystone Species
Removal of a keystone species has substantial ripple effects
– alters the food chain
A species that can change an ecosystem through its activities
Engineering Species Make new habitats for other species
But also destroy habitats affecting species living there
A species that spreads widely and rapidly becoming dominant
in a community and changing the community’s normal
functioning
Invasive Species • Many invasive species are non-native, introduced from
other areas - have no natural controls (e.g. predation,
disease, competition) in invaded area
1
