chapter 45 Flashcards
What encompasses the physical habitat and ecological role of a species
Niche
Niche ecology
Interactions ultimately define the realized niche out of the fundamental niche
what is a species fundamental niche?
is how they COULD live in any ecosystem the species realized niche is how they Do live in a specific ecosystem
Species interact in communities
what are communities and Characteristics of communities?
communities- are sets of populations of different species that live in the same area and can potentially interact
Characteristics of communities include
- the species that are present
-The abundance of each species
-how the species interact
- NICHE!!!
Competition, predation, parasitism, and herbivory are interactions in which?
at least one species is harmed
The effect of an ANTAGONISTIC interaction on an individual can be
Beneficial (+), harmful(-) or null (0)
Antagonistic interactions
Several interactions involve a winner and a loser, usually a feeder and a feedee
competition
interspecific and infraspecific
Predation
Species A captures, kills, and feeds on individual of species B
Predation – Generalist
not usually a species- specific interaction
Some predators are highly evolved for efficiency at capturing one specific species of prey- Specialists
Herbivory
Species A captures and feeds on Specific B Specialists or generalists
Parasitism
- Usually species- specific
- can be a pretty complex relationship
Interspecific competition
occurs when different species use the same limiting resources (space, food , light, silence, mate, water)
Infraspecific competition
When individuals of the same species use the same limiting resources
competitive exclusion
two species with similar niches will clash competitively over limiting resources, therefor one will always the loser and one the winner
Resource partitioning and Exclusion
- competirive exclusion played out over time results in initially similar species diverging in habitat use and feeding strategies
- This process is known as resource partitioning, in which species whose niches overlap diverge and become different subspecies or species
- The result is that the overlap between closely related groups is minimized
Resource Partitioning
Driving a reduction in competition between closely related groups or those who use the same resources in very similar ways
what does Habitat diversity promotes ?
Species coexistence
- How can predators and prey coxist?
- Habitat refuges allow prey populations to persist
- with refuges we see cycles of increase and decline of both predators and prey community Ecology!
Predation
Predators often exert to TOP-DOWN CONTROL on prey populations ( and others) in ecological time
- American Chestnut example
- Fungus attacks vascular system chestnut dies
- Chestnut poop’n declines
- Oak, Beech, poplar Pop’ns increase
in what interactions do both species benefits?
Mutualisms
Mutualims
are usually specific obligate relationships
- Obligate means absolutely required Rather than “facultative” or optional
The Mutualistic relationship often involves?
physiological dependence of one on the other
- it is specific partnership of two or more species
-Mutualism’s are product of a long coevolutionary process ( Lots of adaptation )
Mutualisms can be ?
symbiotic realtionships
Buchnera and Aphids
Aphids: essential amino acids from bacteria
BAteria: stable, favorable environment in which to live
Aphids: loss of sugar
Bacteria: Loss of some nutrients
Bacteria passed from mother aphids to daughter in egg cells
commensalisms
are interactions in which one species benefits and the other ha zero impact (beneficial+)
Facilitation
is a type of indirect interaction where one species creates a suitable habitat for another
Examples-
- Trees may alter the amount of sunlight that reaches the forest floor, creating conditions that benefit particular understory plants
- Kelp forests in the oceans can create suitable habitat for other species.
communities are composed of local population of multiple species that may interact with each other
Biodiversity!!
communities
A community is composed of local populations of multiple species that may interact with one another
biodiversity
Biodiversity includes diversity of
- genetic sequences,
- Cell types,
- Species,
-Life histories,
-Phylogenetic groups ,
-Communities ,
- Ecosystem
Species diversity is an important attribute of
community structure
- It is critical to understand the impact of biodiversity losses
-community diversity affects ecological functions and dynamics
- diverse communities should capture more resources and produce more biomass
-This implies that places in which biodiversity is reduced will support less life overall
Keystone species
When the integrity of community depends on the presence of a stable population of a single species.
Ecosystem Engineers
a type of keystone species.
- Actively shaping the physical environment around themselves
-Secondarily creating habitat for others
Succession
A process of recovery from disturbance
Disturbance depopulate the community and releases resources
- fire is a regular agent of disturbance in prairie communities and many forests
storms cause tree fall that create light gaps in the forests canopy
diversification
Not all species “arrived”
some are the result of diversification of immigrants into a vanity of niches
Species that evolved in situ are ENDEMIC SPECIES
Habitat diversity can lead to departures from simple island biogeography predictions.
