Download Biology Chapter 20 Communities Notes Outline Section 20

Biology
Chapter 20 Communities
Notes Outline
Section 20-1 Species Interactions
Objectives
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Identify two types of predator adaptations and two types of prey adaptations.
Identify possible causes and results of interspecific competition.
Compare parasitism, mutualism, and commensalism, and give one example of each.
A. Introduction: Ecosystem Diversity
1. _________________________ are among the most diverse and productive marine ecosystems on Earth
a. Animals take advantage of a coral reef because it serves as a ________________, a place to find
____________, _________________ from predators, or for a surface to _______________ on.
b. A coral reef community is so rich in the _______________ and _________________ of
organisms because there are many opportunities for _________________, ________________,
and ______________________ between organisms.
c. The coral reef provides many _____________________ and ____________________ to exploit.
2. Just as _______________________ contain interacting members of a single species,
____________________ contain interacting populations of many species.
B. Predation
3. In _____________________, an individual in one species, called the ________________________, eats
all or part of another individual of another species, called the ___________________.
4. Predation is a ______________________ force in a community.
a. The relationship between predator and prey influences the __________________ of each
population and affects ___________________ and ____________________ each species lives.
b. Examples of predators include _______________________, predators that eat animals, and
_______________________, predators that eat plants.
5. All ________________________ are either predators or parasites or both.
C. Predator Adaptations
6. ____________________________ favors the evolution of predator adaptations for
__________________, _____________________, and ______________________ prey.
a. For example, a rattlesnake has an acute sense of _____________________ and heat-sensitive
____________________ located below each nostril. These pits enable the rattlesnake to detect
warm-bodied prey, even in the ____________________.
b. Many snakes use ___________________ to disable or kill their prey.
7. Other predator adaptations include:
a. The __________________________ of spiders
b. Flesh-cutting _______________________ of wolves and coyotes
c. ___________________ of cheetahs
d. Striped pattern of a tiger’s coat which provides _____________________
e. Herbivores have mouth parts for ________________ and _______________ tough vegetation
8. A predator’s survival depends on its ability to capture ______________, but a prey’s survival depends on
its ability to avoid being ________________________.
D. Adaptations in Animal Prey
9. Animals avoid being eaten by predators in many different ways:
a. _________________________________
b. _________________________________
c. _________________________________
d. _________________________________
e. _________________________________ – one species closely resembles another species
E. Adaptations in Plant Prey
10. Plants cannot _________________ from a predator, but many plants escape predation in many ways:
a. Physical defenses
1) ______________________________
2) ______________________________
3) ______________________________
4) ______________________________
b. Chemical defenses
1) ______________________________ chemicals, like strychnine and nicotine
2) ______________________________ chemicals
3) ______________________________ chemicals
F. Competition
11. ________________________________ is a type of interaction in which two or more species use the
_________________________ limited resource.
12. ________________________________ occurs when one species is ______________________ from a
community because of competition for the same _____________________.
13. Reduce Niche Size
a. The ________________________ niche is the range of conditions that a species can
______________________ tolerate and the range of resources that it can potentially use.
b. The ________________________ niche is the part of the niche that the species
______________________ uses.
14. Character Displacement
a. Competition may drive the evolution of niche differences among competitors. This evolution of
differences in a characteristic due to competition is called ______________________________.
b. Character displacement is a way of reducing niche _____________________.
15. Resource Partitioning
a. Competition is likely to be most ______________________ between ______________________
species that require the ________________________ resources.
b. _________________________ resource use to avoid competition is called
__________________________________________.
G. Symbiosis
16. In ________________________, one species (the ____________________) feeds on, but does not
always kill, another species (the _____________________).
17. In ________________________, both interacting species ______________________.
18. In ________________________, one species ___________________, and the other is
_______________________.
*** Assignment: Answer the 20-1 Section Review questions #1-9 page 404.
20-2 Patterns in Communities
Objectives
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Describe the factors that affect species richness in a community.
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Explain how disturbances affect community stability.
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Distinguish between types of succession, and explain why succession may not be predictable.
A. Species Richness
1. One characteristics of a community is _______________________________, the _________________ of
species in the community.
2. A related measure is __________________________________, which is the
________________________________________ of each species.
B. Latitude and Species Richness
3. Species richness varies with ______________________ (distance from the equator).
4. As a general rule, the __________________ the community is to the equator, the ________________
species it will contain.
5. One hypothesis is that temperate habitats, having formed since the last Ice Age are ________________.
Therefore, tropical habitats were ______________________________ by the ice ages, but habitats
closer to the ___________________ were disturbed. Since the climate is ________________________
in the tropics, the species can __________________________ to a greater degree than in regions where
the climate is more __________________________.
6. Another hypothesis is that because plants can photosynthesize _______________________ in the
tropics, ___________________________ is available to support ____________________ organisms.
C. Habitat Size and Species Richness
7. Another pattern of species richness is that _______________________ areas usually have
_________________________ than smaller areas do, called _____________________________.
8. The species area effect is most often applied to _____________________ where area is clearly limited
by ___________________________.
9. Reducing the size of a habitat __________________ the number of species that the habitat can support.
D. Species Interactions and Species Richness
10. Species interactions such as __________________________ can promote species richness.
11. Predators can prevent ____________________________________ among their prey.
E. Community Stability and Species Richness
12. _______________________________ can alter a community by _______________________ or
____________________________ organisms or altering resource __________________________.
13. Disturbances affect practically _________________ communities at some point. Some species
_______________________ on a certain type of disturbance for _______________________.
14. __________________________ is the tendency of a community to maintain relatively
__________________________ conditions (resist disturbances).
F. Successional Changes in Communities
15. The gradual, sequential regrowth of a community species in an area is called ______________________.
16. Ecologists recognize two types of succession:
a. ____________________________ is the development of a community in an area that has not
supported life previously, such as ____________________, a ___________________, or an
island formed by a __________________________________.
b. ____________________________ is the sequential replacement of species that follows
disruption of an existing community by a natural disturbance, such as a ___________________,
_________________________, or __________________________.
17. The species of organisms that predominate early in succession are called ________________________.
G. Primary Succession
18. ___________________________ is the assembly of a community on newly created habitat.
19. Primary succession occurs in areas that have been recently exposed to the elements and ____________.
H. Secondary Succession
20. ___________________________ is the change in an existing community following a disturbance.
21. Secondary succession occurs in areas where the original ecosystem has been cleared by a ___________.
I. The Complexity of Succession
22. The traditional description of succession is that the community proceeds through a predictable series of
stages until it reaches a stable end point, called the _________________________________.
23. Primary succession typically proceeds from ________________ and __________________ to a climax
community.
24. Secondary succession typically proceeds from _____________________ to a climax community.
*** Assignment: Answer the 20-2 Review Questions #1-8 page 410.