15 Questions
Which of the following is a keystone host species mentioned in the text?
Saguaro cactus
What is the role of keystone prey species?
To maintain their numbers despite being preyed upon
What is the effect of keystone species on community structure?
They control the diversity of species
What type of environment are Saguaro cacti found in?
Deserts
Which of the following is NOT mentioned as a keystone host species in the text?
Beaver
According to the text, what is a fundamental niche?
The resources and habitat that the species could theoretically use.
According to the text, what is a realized niche?
The resources and habitat that the species is actually able to use.
According to the text, what can natural selection do in terms of niches?
Evolve species to have both broad tolerance and specialized adaptations.
According to the text, what are structural adaptations?
Body anatomy adaptations that help the organism survive in the niche.
According to the text, why can't two species with identical niches survive indefinitely in the same habitat?
Because they will compete with each other for resources.
Which of the following statements is true about keystone species?
Keystone species have a disproportionate effect on the structure of an ecological community.
What happened to the species diversity in the study area after the removal of the starfish?
Species diversity decreased.
What is the main role of sea otters in the ecosystem?
To regulate sea urchin populations.
How did the removal of the starfish affect the intertidal area?
The area became dominated by barnacles and mussels.
What is the role of keystone modifier species like the North American beaver?
To determine the prevalence and activities of many other species.
Study Notes
Keystone Species
- Keystone host species mentioned in the text: starfish
- Keystone prey species: play a crucial role in maintaining the structure of their ecosystems
Niche and Adaptation
- Fundamental niche: the full range of environmental conditions and resources in which a species can survive and reproduce
- Realized niche: the portion of the fundamental niche that a species actually occupies due to interactions with other species
- Natural selection can lead to the creation of new niches or the shifting of realized niches
- Structural adaptations: specialized physical features that allow an organism to interact with its environment in a unique way
Community Structure and Biodiversity
- Keystone species have a disproportionate impact on community structure and biodiversity
- Removal of a keystone species can lead to a decline in species diversity (e.g., removal of starfish led to a decrease in species diversity in the study area)
Ecosystem Engineers
- Keystone modifier species like the North American beaver play a crucial role in shaping their ecosystems through their activities (e.g., building dams)
Intertidal Ecosystems
- Sea otters play a key role in maintaining the balance of their ecosystems by preying on sea urchins that might otherwise overgraze kelp forests
- Removal of starfish led to an overgrowth of algae in the intertidal area
Test your knowledge about ecological niches and population dynamics with this quiz. Learn about the impact of predation on population density using a fascinating example of fish populations.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
