Title: Niche,%20Community%20Interactions%20and%20Succession
1Niche, Community Interactions and Succession
Chapter 19
2Niche
- A niche is the range of physical and biological
conditions in which a species lives and the way
the species obtains what it needs to survive and
reproduce.
3Tolerance
- Every species has its own range of tolerance, the
ability to survive and reproduce under a range of
environmental circumstances.
4Tolerance
- Organisms have an upper and lower limit of
tolerance for every environmental factor. Beyond
those limits, the organism cannot survive.
5Tolerance
- When an environmental condition, such as
temperature, extends in either direction beyond
an organisms optimum range, the organism
experiences stress. - The organism must expend more energy to maintain
homeostasis, and so has less energy left for
growth and reproduction.
6Habitat
- A species tolerance for environmental
conditions, then, helps determine its habitatthe
general place where an organism lives.
7Niche and Resources
- The term resource can refer to any necessity of
life, such as water, nutrients, light, food, or
space. - For plants, resources can include sunlight,
water, and soil nutrients. - For animals, resources can include nesting space,
shelter, types of food, and places to feed.
8Physical Aspects and Niche
- Part of an organisms niche involves the abiotic
factors it requires for survival. - Most amphibians, for example, lose and absorb
water through their skin, so they must live in
moist places.
9Biological Factors and Niche
- Biological aspects of an organisms niche involve
the biotic factors it requires for survival. - Birds on Christmas Island all live in the same
habitat but they prey on fish of different sizes
and feed in different places.
10- Polar bears live in the arctic. The arctic is
their - a. niche.
- b. habitat.
- c. tolerance.
- d. microclimate.
11- Which of the following is a biological aspect of
an organisms niche? - a. the water in the area
- b. the way it gets food
- c. amount of sunlight
- d. composition of soil
12Competition
- How one organism interacts with other organisms
is an important part of defining its niche. - Competition occurs when organisms attempt to use
the same limited ecological resource in the same
place at the same time.
13Intraspecific Competition
- Competition between members of the same species.
14Interspecific Competition
- Competition between members of different species.
15Competitive Exclusion Principle
- Direct competition between different species
almost always produces a winner and a loserand
the losing species dies out. - Dotted line grown separately
- Solid line grown together
16Competitive Exclusion Principle
- The competitive exclusion principle states that
no two species can occupy exactly the same niche
in exactly the same habitat at exactly the same
time.
17Dividing Resources
- Instead of competing for similar resources,
species usually divide them.
18Dividing Resources
- The resources utilized by these species are
similar yet different. Therefore, each species
has its own niche and competition is minimized.
19- No two species can occupy the same niche in the
same habitat at the same time - a. because of the interactions that shape the
ecosystem. - b. unless the species require different abiotic
factors. - c. because of the competitive exclusion
principle. - d. unless the species require different biotic
factors.
20- Several species of warblers can live in the same
spruce tree ONLY because they - a. have different habitats within the tree.
- b. dont eat food from the tree.
- c. occupy different niches within the tree.
- d. can find different temperatures within the
tree.
21Predator-Prey Relationships
- An interaction in which one animal (the predator)
captures and feeds on another animal (the prey)
is called predation.
22Predator Prey Relationships
- Predators can affect the size of prey populations
in a community and determine the places prey can
live and feed. - Idealized computer model
23Herbivore Plant Relationship
- An interaction in which one animal (the
herbivore) feeds on producers (such as plants) is
called herbivory.
24Herbivore Plant Relationship
- Herbivores, like a ring-tailed lemur, can affect
both the size and distribution of plant
populations in a community and determine the
places that certain plants can survive and grow.
25Keystone Species
- A keystone species is one whose impact on its
community or ecosystem is disproportionately
large relative to its abundance .
26Keystone Species
- A species whose very presence contributes to the
diversity of life and whose extinction would
result in the extinction of species dependant on
it.
27Symbiosis
- The close and often long-term interactions
between biological species. - Mutualism
- Parasitism
- Commensalism
28Mutualism
- Also known as cooperation.
- Both organisms gain a fitness benefit.
- Ex, clown fish and anemone
29Parasitism
- Relationships in which one organism lives inside
or on another organism and harms it. - Generally, parasites weaken but do not kill their
host, which is usually larger than the parasite.
30Commensalism
- A relationship in which one organism benefits and
the other is neither helped nor harmed. - Ex, barnacles on whale
31Succession
- Ecosystems change over time, especially after
disturbances, as some species die out and new
species move in. - Ecological succession is a series of more-or-less
predictable changes that occur in a community
over time.
32- A symbiotic relationship in which both species
benefit is - a. commensalism.
- b. mutualism.
- c. predation.
- d. parasitism.
33- A symbiotic relationship in which one organism is
harmed and the other benefits is - a. mutualism.
- b. parasitism.
- c. commensalism.
- d. predation.
34Primary Succession
- Volcanic explosions can create new land or
sterilize existing areas. - Retreating glaciers can have the same effect,
leaving only exposed bare rock behind them.
35Primary Succession
- Succession that begins in an area with no
remnants of an older community is called primary
succession.
36Primary Succession
- The first species to colonize barren areas are
called pioneer species. - One ecological pioneer that grows on bare rock is
lichena mutualistic symbiosis between a fungus
and an alga.
37Secondary Succession
- Sometimes, existing communities are not
completely destroyed by disturbances. In these
situations, secondary succession occurs.
38Secondary Succession
- Secondary succession proceeds faster than primary
succession, in part because soil survives the
disturbance. As a result, new and surviving
vegetation can regrow rapidly.
39Why Does Succession Occur?
- Every organism changes the environment it lives
in. - One model of succession suggests that as one
species alters its environment, other species
find it easier to compete for resources and
survive.
40Succession after Disturbance
- Healthy coral reefs and tropical rain forests
often recover from storms, and healthy temperate
forests and grasslands recover from wildfires.
41Succession after Human-Disturbance
- Ecosystems may or may not recover from extensive
human-caused disturbances. - Clearing and farming of tropical rain forests,
for example, can change the microclimate and soil
enough to prevent regrowth of the original
community.
42- Primary succession would most likely occur after
- a. a forest fire.
- b. a lava flow.
- c. farm land is abandoned.
- d. a severe storm.
43- An example of a human-caused disturbance is
- a. a hurricane.
- b. forest-clearing.
- c. wildfires.
- d. growing lichens.
44- What is one difference between primary and
secondary succession? - a. Primary succession is rapid and secondary
succession is slow. - b. Secondary succession begins on soil and
primary succession begins on newly exposed
surfaces. - c. Primary succession modifies the environment
and secondary succession does not. - d. Secondary succession begins with lichens and
primary succession begins with trees.
45Chapter 21 BIOMES
- https//www.youtube.com/watch?vv7cZ3b6PH2s
- Grassland
- Tundra
- Tropical rainforest
- Taiga
- Desert
- Deciduous forest
- Marine
- freshwater
https//www.youtube.com/watch?vv7cZ3b6PH2s