Chapter 13: Species interactions, population dynamics, and natural selection Flashcards
List population interactions between individuals of two species?
- neutral
- mutualistic
- commensalism
- competition
- amensalism
- predation
- parasitism
- parasatoidism
Population interactions between individuals of two species:
- Neutral?
- species a and species b do not harm or benefit each other..they are just occurring at the same place and time
Population interactions between individuals of two species:
- Mutualism?
- both species benefit from having the other there
Population interactions between individuals of two species:
- Commensalism?
-one species benefits but the other does not BUT the other species is not harmed
Population interactions between individuals of two species:
- competition?
- negative for both species…competing for a resource..limiting the resource for both species
Population interactions between individuals of two species:
- Amensalism?
- the opposite of commensalism..interaction between the species is having a negative impact on one and neutral for the other
Population interactions between individuals of two species:
- Predation?
- positive(predator) and negative (prey dies)
Population interactions between individuals of two species:
- parasitism ?
- host is not benefiting form the interaction…parasite benefiting
Population interactions between individuals of two species:
- parasatoidism?
- positive for the parastoid but not the host
* *attached to a host not in the host
- 2 Species interactions influence population dynamics:
- interactions with other species alter what?
- birth and death rats of populations
ex: if a predator is preying on other species..it is gaining nutrients etc making it more fit..prey is not mating…etc it died
- 3 Species interactions as agents of natural selection:
- Phenotypic variations among individuals affect?
- nature and degree of interactions
- these phenotypic differences in the degree of interaction may influence fitness, resulting in natural selection
- *some interactions are both physiological and behavioural but ALL influenced by phenotypes
- 3 Species interactions as agents of natural selection:
- do interactions affect all individuals in a population?
- no
Coevolution?
- process of reciprocal evolutionary change through natural selection
- adaptation to another species can occur to thwart adaptive changes (e.g. predator-prey arms race) or reinforce mutually beneficial effect
Describe the coevolution example with the hummingbird and plants?
- mutual relationship
- humming bird eats nectar…if a plant produces more nectar they will preferentially feed on that plant. As this plat starts t get bigger it has more nectar available and the plant wants this because the humming bird is cross pollinating via increasing dispersal
- *As the flower gets longer and more nectar the hummingbird wants to feed more so its beak size adapts….and it gets larger and becomes favoured.
As the hummingbird and flower coevolve to each other what happens in terms of specialization ?
- they become highly specialized for each other…..limiting the amount of pollinators that can come and pollinate so if one of these species was to be lost the other would follow as well. (food source for one and reproduction for the other)
therefore increased specialization = increased risk of extinction