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2. An ecological niche is the role and
position a species has in its
environment; how it meets its
needs for food and shelter, how it
survives, and how it reproduces.
A species' niche includes all of its
interactions with the biotic and
abiotic factors of its environment.

3. Fig 1: and abiotic factor at ecological niche

4. Concept of Ecological Niche:
For a species to maintain its
population, its individuals must
survive and reproduce.
The fundamental niche of a species
includes the total range of
environmental conditions that are
suitable for existence without the
influence of interspecific
competition or predation from
other species.

5. The ecological niche describes how
a species interacts within an
ecosystem.
The niche of a species depends on
both biotic and abiotic factors,
which affect the ability of a species
to survive and endure

6. Fig 2: Species interaction ecological niche

7. Biotic factors affecting a species'
niche include food availability and
predators.
Abiotic factors affecting ecological
niche include temperature,
landscape characteristics, soil
nutrients, light and other non-
living factors.

8. An example of an ecological niche
is that of the dung beetle.
The dung beetle, as its name
suggests, consumes dung both in
larval and adult form.
Dung beetles store dung balls in
burrows, and females lay eggs
within them

9. Fig 3: Ecological niche of the dung beetle

10. The dung beetle in turn influences
the surrounding environment by
aerating soil and rereleasing
beneficial nutrients.
Therefore, the dung beetle
performs a unique role in its
environment.

11. Importance of Ecological Niches
Ecologists use the concept of the
ecological niche to help understand
how communities relate to
environmental conditions, fitness,
trait evolution and predator-prey
interactions in communities.
This becomes ever more important as
climate change affects community
ecology.

12. Interspecies competition:
Ecologists refer
to coexistence when describing
ecological niches. Two competing
species cannot exist in one
ecological niche. This is due to
limited resources.
Some species of ants, the insects
will compete for nests and prey as
well as water and food.

13. Fig 4: Interspecies competition ecological niche

14. Competitive exclusion principle:
Ecologists use the competitive
exclusion principle to help
understand how species coexist.
The competitive exclusion
principle dictates that two species
cannot exist in the same ecological
niche. This is due to competition
for resources in a habitat.

15. Fig 5: Species coexist ecological niche

16. In R* Theory, multiple species
cannot exist with the same
resources unless they differentiate
their niches.
When resource density is at its
lowest, those species populations
most limited by the resource will
be competitively excluded.

17. In P* Theory, consumers can exist at
high density due to having shared
enemies.
Competition plays out even at the
microbial level.
For example, if Paramecium
aurelia and Paramecium
caudatum are grown together, they
will compete for resources. P.
aurelia will eventually overtake P.
caudatum and cause it to go extinct.

18. Fig 6: Competational growth at ecological niche

19. Overlapping Niches
Given the fact that organisms
cannot exist in a bubble and must
therefore naturally interact with
other species, occasionally niches
can overlap.
To avoid competitive exclusion,
similar species can change over
time to use different resources.

20. Fig 7: Overlapping Niches

21. Resource partitioning: Partitioning
means separating. Simply put, species
can use their resources in ways that
reduce depletion. This allows the
species to coexist and even evolve.
Ex: Dolphins and Seals, which eat
similar species of fish. However, their
home ranges differ, allowing for a
partitioning of resources.

22. Fig 8: Resource partitioning niches

23. in the jack pine forest of
Michigan, the Kirtland’s warbler
occupies an area ideally suited
for the bird.
The birds prefer nesting on the
ground between the trees, not in
them, among small undergrowth.

24. Fig 9: Warbler nesting niches