Chapter37 Communities and Eco systems Flashcards
What is a community?
Collection of populations living close enough to each other for potential interactions
Why is community ecology important?
- Conservation and management of game, wildlife and fisheries
- Conservation of endangered species
- Helps control diseases such as malaria and flu
- Applications in agriculture
What are interspecific interactions?
Relationships with individuals of other species in the community.
How can one classify interspecific interactions?
Harmful to the population (denoted by - sign) or helpful or favorable to a population (denoted by + sign)
What are the interspecific interactions among species?
- Interspecific competition
- Mutualism
- Predation
- Herbivory
- Parasites and pathogens
What is interspecific competition?
Populations of two species compete for a scarce resource.
E.g: Squirrels and Bears compete for acorns
What is mutualism?
An interspecific interaction where both species benefit from it.
E.g: Herbivores and Cellulose digesting microbes
Digesting food for the herbivore +
Food to produce energy for the microbe +
What is predation?
One species kills the other species and eats it
What is herbivory?
Consumption of plant parts and algae by herbivores
What is the effect of interspecific interactions on species?
Interspecific competition Species 1 (-) Species 2(-)
Mutualism Species 1(+) Species 2(+)
Predation Predator (+) Prey (-)
Herbivory Herbivore (+) Plants/Algae (-)
Parasites/Pathogens Parasite/Pathogen (+) Host(-)
What is an ecological niche?
Sum of the use or consumption of abiotic and biotic factors by a species in an environment.
E.g: Nesting sites and material of a bird species
Food it eats and amount of water it consumes
How does interspecific competition occur?
When ecological niches of species intersect
What are examples of interspecific competiton?
- Desert plants compete for water
- Plants in rain forests compete for light
- Bears and squirrels compete for acorns
What will have more severe effects on a popuation? Inter specific competition or intra specific competition?
Intra specific competition because the same species has the same biological niche and therefore the resources may be consumed sooner
Give examples of mutualism?
- Corals and Dinoflagellates
a. Dinoflagellates live inside the crevices(cells) of the corals and gets security and shelter that provide access to light
b. Dinoflagellates produce sugars by photosynthesis that is used by the corals to produce energy
c, Dinoflagellates consumes corals waste materials
What are the evolutionary adaptations of prey to avoid being killed?
- Camouflage
- Mechanical defenses such as quills and hard shells
- Chemical defenses such as secretion of pungent or poisonous chemicals
Explain how predation helps adaptive evolution?
Surviving prey will pass on the allels that will result in offspring inheriting the characteristics that can successfully defend against the predator
What is coevolution?
Change in one species acts as a new selection force to another species in turn would would affect the selection of individuals in the first species
What are plants defense against herbivory?
- Thorns and spines
2. Chemical defenses such as pungent odor or bad taste or poisonous substances
Why do we have bitter tasting receptors ?
Individuals having bitter tasting receptors has a higher chance of detecting harmful or poisonous food and hence has a better chance of survival.
What is a parasite?
An organism relying on a host (the other organism) in a way harmful to the other organism without killing it.