Unit 5 (Ecology- Biotic Factors)🧡 Flashcards
What is a Habitat?
The physical location occupied by a species.
What is a Niche?
This refers to the total use of biotic and abiotic resources by a species. (Way of life)
What is the Interspecific Competition for Resources?
This refers to when multiple species have overlapping niches and have to compete for the same resource.
How does Natural Selection interact with the Interspecific Competition for Resources phenomenon?
Natural selection makes it so that niches rarely overlap. Animals that don’t have to compete for a resource tend to survive longer.
What are the two possible results from interspecific resource competition?
- Resource Partitioning
- Extinction
What is Resource Partitioning?
The evolution of one or both species away from the niche overlap.
What are the two kinds of resource partitioning?
- Morphological (character displacement-physical change)
- Behavioral (ex. forage at different times)
What is the Competition Exclusion Principle?
No two species can STABLY occupy identical niches.
List three predator avoidance strategies plants have adopted.
- Trichomes
- Toxicity
- Mimicry
What are Trichomes?
Thorns, Spines, or spikey “fuzz.”
What does it mean to be a 2nd compound?
A molecule that is toxic to predators but has no metabolic function in a plant. (It exists to be a deterrent and that’s it.)
What are some physical and chemical predator avoidance strategies animals have adopted?
-Spines
-Footspeed
-Flight
-Size
-Venom/Toxin
-Coloration/Cryptic
-Aposematic (warning colors)
-Mimicry
(you don’t need to memorize-just understand)
What does it mean for an animal to be Cryptic?
This is a form of camouflage an animal may adopt in order to appear like another organism.
(ex. Stick Bug)
What does it mean for an animal to be Aposematic?
This is a predator deterrent in which the animal has evolved bright colors to indicate danger-usually poison.
(Ex. Poison Dart Frogs)
What does it mean for an animal to engage in Mimicry?
They have evolved to immitate something in their enviornment.
What is Batesian Mimicry?
What is Mullerian Mimicry?
- When a harmless species mimics a dangerous species.
- When two or more unrelated and dangerous creatures resemble each other.
What are some behavioral predator avoidance strategies done by animals?
- Group Living
- Nocturnal
- Fossorial
- Playing Dead
- Aggressive Mimicry
(not memorize-just understand)
What are the two main benefits of Group Living?
- Provides more eyes (to see danger)
- Enables Altruistic Behavior
What is an example of Altruistic Behavior between animals that live together?
Prairie Dogs make warning calls to alert of hawks.
What does it mean for an animal to be Fossorial?
This means that they burrow underground.
What is a Keystone Species?
This is a species that is essential in maintaining biodiversity in an ecosystem.
(ex. Sea Star, Otters)
What happens if you remove a sea star from a very biodiverse tidepool?
Starfish keep mussel populations intact, so without starfish mussels out competes all the other species, driving them all to extinction.
What happens if you remove Otters from their natural habitat?
Otters keep urchin populations intact, so without otters sea urchin population grows and that declines giant kelp population, driving them all to extinction.
How does one identify a keystone species?
You can’t unless you remove the species from it’s environment and watch what happens.
