Week 4 Flashcards
(23 cards)
What is a niche?
Specific set of environmental conditions required by an organism or the functions it performs in nature
A multidimensional hypervolume encompassing all environmental factors influencing a species.
How does a niche differ from a habitat?
‘Niche’ refers to both where the organism occurs and what they do there, while ‘habitat’ is where a species lives
Niche includes the function of a species in its environment.
What is the fundamental niche?
Includes all the features of a habitat potentially available to a population
What is the realized niche?
The subset of features of that habitat actually occupied by the population, constrained by competitors/predators
What is ‘phylogenetic niche conservatism’?
Groups of species within the same family or order have relatively similar niches because they evolved from a common ancestor
What does interspecific mean?
Interactions between more than one species
What is predation?
A relationship where the predator benefits (+) and the prey is harmed (-)
Define mutualism.
A relationship where both species benefit (+/+)
What is competition in ecological terms?
A relationship where one species benefits (+) and the other is harmed (-)
What is the competitive exclusion principle?
Two species cannot occupy the same niche in a habitat
What adaptations do predators have to find prey?
Acute senses, ambush tactics, and speed/agility
What are anti-herbivory adaptations?
Secondary compounds/metabolites that protect plants against herbivory
How is symbiosis defined?
A close, prolonged association between two or more different biological species
What types of relationships can symbiosis include?
- Mutualistic (+/+)
- Parasitic (+/-)
What is a biological community?
A collection of species that occur together in the same place or habitat
What is biodiversity?
A measure of the number of species in a given area
What is the sub-field of ecology that studies community patterns?
Community Ecology
What is species richness?
The simplest measure of biodiversity, counting the number of species
What is the Shannon Weiner Diversity Index (H or H’)?
A formula to measure species diversity in a community: H = -(pAln pA)+(pBln pB)+…
What does a higher H value indicate?
Habitats with more species and a more even distribution of species
What is allopatric speciation?
When a species separates into two groups isolated by a physical barrier
What factors affect biodiversity?
- Energy and nutrients through primary productivity
- Water
- Disturbance
- Invasive species
- Predation
- Succession
- Biogeographic factors
What are ecological traps?
Habitat areas that attract animals but compromise their fitness due to poor quality
