Title: Biological Diversity or Biodiversity
1Biological Diversity
Biological Diversity or Biodiversity The sum
total of all organisms in an area, taking into
account their genes, their populations, and their
communities Species A particular type of
organism, a population or group of populations
whose members freely breed with one another and
produce fertile offspring Speciation The process
by which new species are generated.
2Biological Diversity
Allopatric Speciation The formation of species in
separate locations. How might this happen?
3Biological Diversity
Sympatric Speciation The formation of species
together in a single location without
geographical speciation How might this happen?
4Biological Diversity
Phylogenetic Trees or Cladograms A family tree
based upon how scientists believe species
divergence took place Extinction The
disappearance of an entire species from the face
of the earth Endemic When a species only occurs
in that particular place on the planet
5Biological Diversity
Background Extinction Extinction happening one
species at a time. Mass Extinction Events that
killed off massive number of species all at once.
The earth has experienced five mass extinction
events wiping out 50 to 95 of species at one
time. Humans may be causing a 6th mass
extinction.
6Hierarchy of Biological Organization
See figure 5.7 Atom The smallest component of an
element that maintains the elements chemical
properties Molecule A combination of two or more
atoms chemically bonded together
7Hierarchy of Biological Organization
Cell The smallest unit of living matter able to
function independently, enclosed in a
semi-permeable membrane Tissue A group of cells
with a common structure and function Organ A
structure in an organism composed of several
different types of tissues and specialized for
some particular function
8Hierarchy of Biological Organization
Organism An individual living thing Population A
group of individuals of a species that live in a
particular area Community A set of populations
of different species living together in a
particular area
9Hierarchy of Biological Organization
Ecosystem A functional system consisting of a
community, its non-living environment, and the
interactions between them Biosphere The sum
total of living things on Earth and the areas
they inhabit
10More Ecology Terms
Habitat The specific environment in which an
organism lives consisting of living and
non-living things Habitat Selection The process
by which an organism selects a habitat in which
to live Niche Functional role in a community
including the use of certain habitats,
consumption of certain foods, and interaction
with other organisms
11Population Ecology
Population Size The number of individual
organisms present at a given time Population
Density The number of individuals within a
population per unit area Population Distribution
or Dispersion The spatial arrangement of organisms
12Population Ecology
Random Distribution Individuals are located
haphazardly in space with no particular
pattern Uniform Distribution Individuals are
evenly spread out Clumped Distribution (Most
common pattern in nature) Organisms arrange
themselves according to resource availability and
hence are clumped in spatial distribution
13Population Ecology
Age Distribution or Structure Describes the
relative numbers of organisms of a certain age in
a population Age Structure Diagrams or
Pyramids See Figure 5.9 Sex Ratio Proportion of
males to females in a population
14Population Ecology
Growth Rate How a population changes in
size Population size changes based on Births,
deaths, immigration, and emigration GR (Birth
Immigration) (Death Emigration) Immigration
Arrival of individuals from outside the
population Emigration Departure of individuals
from the population
15Population Ecology
Exponential Growth When a population increases by
a fixed percent each year Population Growth
Curves See examples on page 137. Note Population
size on Y axis and time on X axis Population
Limiting Factors Physical, chemical, or
biological characteristics that restrain
population growth
16Population Ecology
Carrying Capacity Maximum population size that a
given environment can sustain Logistic Growth
Curve Figure 5.11 Rises sharply and then begins
to level off as limiting factors become more
limiting Environmental Resistance The force of
the limiting factors which stabilize a
population Carrying capacities can change
because environmental factors change
17Population Ecology
Density Dependent Factors A limiting factor whose
effects on a population increase or decrease
depending upon the population density. Examples
Ability to find mates or disease Density
Independent Factors A limiting factor whose
effects are constant regardless of population
density. Examples Temperature extremes, floods,
fires
18Reproductive Strategies
Biotic Potential Reproductive capacity of a
species. Example, fish that reproduce often with
thousands of eggs at a time have high biotic
potential K-Strategists Have low biotic
potential. They only produce a few offspring and
invest considerable energy into raising each
one R-Strategists Have high biotic potential.
They produce numerous offspring over a short
period of time and do invest parental care
19Community Ecology
Community A group of populations of organisms
that live in the same place at the same
time Food Chain or Food Webs Conceptual, visual
representations of community feeding
interactions Tropic Levels Ranks in the feeding
hierarchy. Example Plants -gt Plant Eaters -gt
Predators -gt Top Predators
20Community Ecology
Producers Green plants/ Autotrophs (or
chemotrophs in hydrothermal vents) the first
tropic level Herbivores Plant eaters the
second trophic level Secondary
Consumers Predators the third trophic
level Tertiary Consumers Top Predators (eat
lower predators) the forth trophic level
21Community Ecology
Carnivores Animals that just eat other
animals Herbivores Animals that just eat
plants Omnivores Animals that eat both plants
and animals
22Community Ecology
Detritivores Animals that eat waste products or
dead bodies of other organisms (scavengers are an
example) Decomposers Break down non-living
organic matter into simpler parts that can be
used by plants
23Community Ecology
Keystone Species A species that has particularly
far reaches effects on a community. A species
whose very presence contributes to a diversity of
life and whose extinction would consequently lead
to the extinction of other forms of life.
Keystone species help to support the ecosystem
(entire community of life) of which they are a
part. Why is the sea otter a keystone
species? Why is the prairie dog a keystone
species? Why is the eastern oyster a keystone
species?
24Community Ecology
Symbiosis A parasitic or mutualistic relationship
between organisms Parasitic Relationship A
relationship in which one organism, a parasite,
secures its nourishment by living on or inside a
host organism at the expense of its host. Host is
not killed Mutualistic Relationship Two species
living together in a relationship in which both
benefit from the association
25Community Ecology
Predation When one species hunts, tracks,
captures, and eats another (the prey) How will
predation affect population size? How will
predation affect evolution?
26Community Ecology
Herbivory Animals eating plants Competition When
multiple organisms seek the same limited
resources. Interspecific Competion Competition
between different species Intraspecific
Competition Competition between members of the
same species Can you think of an example of each?
27Community Ecology
Competitive Exclusion When one species excludes
another from a resource (Example Wolves and
coyotes in MD) Species Coexistence When no
outside influence disrupts the relationship
between two species and the species live side by
side in a certain ratio of population
sizes Equilibrium The point in species
Coexistence when the population size of each
species remains fairly constant.
28Community Ecology
Fundamental Niche The full niche of a species.
Example coyotes could survive throughout the
United States Realized Niche An individual that
play only part of its ecological role because of
competition. Example Coyotes originally
limited to great plains by competition with wolves
29Community Ecology
Resource Partitioning When two or more different
species divide up a resource. Example Hawks
and Owls both eat field mice. Hawks eat them
during the day and owls eat them at night.
30Community Ecology
Parasitism When one organism depend upon another,
a host, for nourishment, doing the host harm but
generally not killing it Endoparasites Parasites
that live inside of a host Ectoparasites Parasite
s that live on the outside of a host Can you
think of an example of each?
31Community Ecology
Mutualism A relationship in which all
participating organisms benefit from their
interaction. Example Pollination How is
pollination and example of mutualism?
32Community Ecology
Amensalism A relationship in which one organism
is harmed and the other is unaffected Example
Large trees shading small trees Commensalism A
relationship in which one species benefits and
the other is unaffected Example Orchid growing
on a tree
33Community Ecology
Anthropogenic Climate Change Human caused climate
change Loss of the golden toad at Monteverde
34Community Ecology
Succession A series of regular, predictable,
quantifiable changes that a community undergoes
in a time span of years to decades The following
refers to succession in terrestrial
communities Primary Succession A process of
community changes which begins when bare rock,
sand, or sediment is first exposed
35Primary Succession
- Rock, sand or sediment is exposed by volcanoes,
sea level drop, glaciers retreating etc. - 2. Pioneer species, species that arrive first,
begin t colonize the area. Pioneer species can
travel long distances and don not require fertile
soil. Lichens, a mutualistic aggregation of
fungi and algae are a pioneer species. They can
grow on bare rock. - 3. As they do, they begin to break down the rock
and turn it into soil.
36Primary Succession
- 4. The newly formed soil can support small
plants, insects, and worms. These organisms
further enrich the soil allowing more small
plants to grow. - 5. The new plants begin to shade out and replace
the lichens, these plants create more soil and
shade allowing small shrubs to take hold - The small shrubs begin to shade out and replace
the small plants. This creates habitat that
small trees can take hold in. - 7. Small trees begin to shade out and replace the
shrubs and create habitat for larger tree species
37Primary Succession
8. The Large trees are the final stage and lead
to a climax community which remains in place
until a major disturbance takes place
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39Primary Succession
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41Primary Succession
- The following refers to a pond or lake
- Plants surrounding the pond die and fall into the
water, slowly filling in the pond. Sediments also
fill in the pond. - 2. The more shallow pond can now support shallow
water aquatic plant which help trap sediments and
die filling in the pond - 3. Eventually the pond becomes filled and
terrestrial plants can grow where the pond once
stood
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43Secondary Succession
Secondary succession is much like primary
succession except that it occurs where there was
already a living community that was disturbed.
An example would be a forest burning down from a
fire or a beaver creating a pond. Soil and some
biotic vestiges of the original community remain
which speeds up the succession process.
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45Community Ecology
Invasive Species Any species that spreads widely
and rapidly become dominant in the community,
interfering with the communities normal
functioning
46Conservation Biology
Ecotourism Tourism based upon visiting nature
provides money to protect ecosystems Ecological
Restoration Human induced restoration of an
ecosystem Restoration Ecology The science of
research how the original natural system worked
and restoring the system to that condition