Transcript Ecology Introduction Notes

What is ecology?
• Ecology: study of interactions between
organisms and their environment
Ecological research
• Most ecologists use both qualitative and
quantitative research.
• They obtain qualitative information by
observing organisms.
Ecological research
• They obtain
quantitative
data by making
measurements
and carrying out
controlled
experiments in
the field and in
the laboratory.
The nonliving environment: Abiotic
factors
• Abiotic factors: Non-living parts of the
environment
• Examples: wind, temperature, moisture,
light, and soil.
The nonliving environment: Abiotic
factors
• Ecology includes the study of features of the
environment that are not living because these
features are part of an organism’s life.
• Abiotic factors have obvious effects on
living things and often determine which
species survive in a particular environment.
The living environment: Biotic factors
• A key consideration of ecology is that living
organisms affect other living organisms.
• Biotic factors: Living organisms in an
environment
• Examples: plants, animals, fungi, protists,
bacteria
Biotic and abiotic factors form
ecosystems
• Ecosystem: interacting populations in a
biological community and the community’s
abiotic factors.
There are two major kinds of ecosystems—
a. terrestrial ecosystems
b. aquatic ecosystems.
Ecosystem
Biotic and abiotic factors form
ecosystems
Table 2.1 Examples of Ecosystems
Aquatic
Other Sites for
Terrestrial
Ecosystems
Ecosystems
Ecosystems
Human body
Freshwater
• Forest
• Skin
• Old farm field • Pond
• Intestine
• Lake
• Meadow
• Mouth
•
Stream
• Yard
Buildings
• Estuary
• Mold in walls,
• Garden plot
floors, or basement
Salt water
• Empty lot
(marine)
• Ventilation systems
• Compost heap • Ocean
•Bathrooms
Food
• Estuary
• Volcano site
• Any moldy food
• Aquarium
• Rotting log
• Refrigerator
Organisms in Ecosystems
• Habitat:
the place
where an
organism
lives
• Ex: pond
for a
beaver;
tree for
bark
insects
Organisms in Ecosystems
• Habitats can change, and even disappear.
Habitats can change due to both natural and
human causes.
Niche
• Niche: the role or position a species has in its
environment (job)
• Ex: owls control rodent population at night
Symbiosis
• Symbiosis: A relationship in which there is a
close, permanent association between
organisms of different species
• Symbiosis means living together. Three
kinds of symbiosis are recognized:
mutualism, commensalism, and parasitism.
Mutualism
• Mutualism:
both species
benefit
Ex: bacteria in
our gut
Commensalism
• Commensalism:
one species
benefits and the
other species is
unaffected
• Ex: barnacles on
a whale
Parasitism
Parasitism:
one species benefits and another is harmed
Parasitism
• Parasites have evolved in such a way that
they harm, but usually do not kill the host
species. Ex: tapeworm
Question 1
The study of interactions that take place
between organisms and their environment is
__________.
A. abiosis
B. symbiosis
C. ecology
D. biology
The answer is C. Ecology is a branch of biology
that developed from natural history.
Question 3
Which of the following is a biotic factor?
A. moisture
B. soil
C. earthworm
D. light
The answer is C. Biotic factors are all the living
organisms that inhabit an environment.
Question 4
A(n) __________ is a group of organisms, all
of the same species, which interbreed and live
in the same place at the same time.
A. biological community
B. population
C. ecosystem
D. habitat
The answer is B. Communities and ecosystems
are comprised of more than one species.
Habitat refers to the place an organism lives.