Download Topic 1

Unit A: Biological Diversity
Chapter 1Biological Diversity is
Reflected in the
Variety of Life on
earth.
1.1 Examining Diversity
• Biologists have identified over 1.5 million
species of animals and 350 000 species
of plants.
– A species is organisms that have the same
structures and can reproduce with one and
another.
• Is the liger (cross
between a lion and
tiger) a species?
No!
Why not?
• 2 ligers cannot
reproduce.
Understanding Biological Diversity.
• Biological diversity refers to all the
different types of organisms on earth.
Ecosystems
• Ecosystem- the living (biotic) and nonliving (abiotic) things that interact with
each other in a shared environment.
• Examples include
– Aquatic
– Forest
– Mountain
– Boreal Forest
– Prairie
Aquatic Ecosystem
Can you identify the abiotic and
biotic parts of this ecosystem?
The Parts of an Ecosystem
Ecosystem
BioticLiving
AbioticNon-living
CommunityAll the different Animals present
Population- the total number
of a species that is present.
Parts of the Ecosystem..
Diversity within species
• What would happen to an ecosystem if all
the gophers were the same and there
were no diversity within the population?
– Let’s say all the gophers were small, skinny
and there was a cold winter?
Diversity within Communities
• Having a number and a variety of species
in an ecosystem is important. Discuss with
a partner why you think having a number
of species is important to the prairie
ecosystem.
• What might happen if a farmers killed off
all the gophers in the prairie ecosystem?
Could it come back to haunt the farmer?
Species Distribution.
• Look at the following map. Answer this
question…where do we find the most
species and why do you think it is that
way?
Map
Check and Reflect
1.
2.
5.
6.
7.
9.
(page 15 #1,2,5,6,7,9)
Explain what is meant by the term biological
diversity.
In one sentence explain why so many different
organisms exist on earth today?
Summarize in your own words: ecosystem diversity,
community diversity, and genetic diversity.
Compare and contrast the meaning of the words
population and community.
Why is there more biological diversity closer to the
equator then in Canada? (Give reasons)
Explain why preserving biological diversity is important
to life on Earth.
Check & Reflect Pg. 15. 1 - 9 (KEY)
1. Biological Diversity describes the variety of species
and ecosystems on Earth as well as the ecological
processes of which they are a part. It is made up of
three components: ecosystem diversity, community
and species diversity, and genetic diversity.
2. There are so many different kinds of organisms on
Earth because the environment varies a great deal
from place to place. Each different region on Earth
has characteristic species of plants and animals
suited to survival there
Check & Reflect Pg. 15. 1 - 9 (KEY)
5. Ecosystem diversity refers to the different types of
environments on Earth in which living and nonliving things interact. A community is a group of
populations of different species that share the same
resources. Community diversity refers to the
number of different communities that may be found
in a given area. Genetic diversity describes the
variety of genetic material contained within all the
individuals of a species
Check & Reflect Pg. 15. 1 - 9 (KEY)
6. A population describes the members of the same
species that live in a specific area and share
resources. A community describes the populations
of different species that live in the same area.
Populations create communities.
7. Generally there is greater diversity towards the
equator because the climate can support a greater
variety of plants, which, in turn, support a greater
variety of animals by providing food and shelter.
Check & Reflect Pg. 15. 1 - 9 (KEY)
9. Ensuring biological diversity is preserved is important
because the health of the planet depends on
having a variety of ecosystems, communities,
species, and genetic material.
1.2
Interdependence.
Interdependence.
• NO SPECIES CAN SURVIVE BY ITSELF
• For example, humans are dependent on plants
to produce the oxygen we breathe.
• Bees depend on flowers to provide them with
their food- nectar, and plants depend on bees to
spread the pollen to make other plants.
• Decomposers- like bacteria and fungi- break
down the dead organisms of our planet, turning
them into much needed soil.
• https://www.youtube.com/watch?v=ZWuc
OrSOdCs
Predator-Prey Relationships
Lynx vs. Snow-shoe Hare
Predator Prey Relationships
• If the lynx population were to get too high, the
snowshoe hare population would be destroyed.
• If the lynx population were to low, the snowshoe
hare population would explode, and they would
eat too much foliage.
– The deer and other herbivore populations would
starve.
• Eventually the hares would starve too.
• Predators also eat the weak or sick members of
a population, allowing the strong ones to breed
and pass on their traits.
The Food Chain…
Where do the arrows
point to?
What would happen
to this ecosystem if
the local farmers
killed off the rattle
snakes that are
killing their cattle?
Could this come
back to haunt them?
Symbiosis
•
There are 4 major types of relationships
organisms in an ecosystem have. It is called
symbiosis.
Symbiosis- “life together” which describes the
relationships between different species.
1. Predator-Prey
2. Commensalism
3. Mutualism
4. Parasitism
Mutualism
• Mutualism- The relationship of 2 species
benefits both species. We say it is a ++
relationship.
• Can you give an example of Mutualism?
Mutualism
• Normally the anemone is
poisonous to organisms.
• The clown fish has a slime that
protects it from the sting
anemone.
• The clown fish gets a safe home
from predators
• And the clown fish attracts prey
into the deadly anemone.
• +/+
Could this be mutualism?
Commensalism
• This is a relationship where one animal
benefits and the other is neither harmed nor
benefited.
• Its called a +/o relationship.
Example of commensalism
• Barnacles on a whale
hitch a ride to new
homes, food sources
and places to
reproduce.
• The whale is not at all
affected.
• Can you think of
another example?
Another Example
• The plants are growing on
the tree.
• The tree allows them to
get more sun for
photosynthesis.
• The tree is unaffected.
Parasitism
• One organism lives ON or INSIDE another
slowly making the other organism sickerusually the host isn’t killed but in some
cases, it is.
• Its relationship is said to be +/-
Example
• Athletes foot.
• A fungus lives off of
your foot, injuring
your skin and giving
you discomfort.
Can you think of
another
example of
parasitism?
Another Example
• Whip worms grow
inside your intestines
and stomach.
• Can reach 300cm in
length.
• Come from uncooked
meats.
• Use you to get
nourishment from the
food you eat.
Symbiosis
• http://www.youtube.com/watch?v=zSmL2F
1t81Q
NICHE• A niche thoroughly describes
– An organisms role in an ecosystem. Whether
it is a producer, consumer, or decomposer.
– What organism eats- including whether or not
it is herbivore, carnivore, omnivore or
decomposer.
– Where the animal lives
Niche of the Wolf
Which statement best describes the
niche of a wolf in Alberta?
a) The wolf, found throughout the
boreal forests and mountains of
Alberta, is a predator feeding on
herbivores.
b) The wolf, found in the mountains of
Alberta, is a consumer.
c) The wolf is a predator feeding on deer
and moose.
d) The wolf lives exclusively in Banff
National Park in Alberta.
Interspecies Competition
• There is another type
of relationship Interspecies
Competition.
• Two or more species
compete for the same
food; neither benefits.
• Each loses because
certain members die
from starvation.
Resource Partitioning
• Sometimes Interspecies
competition leads to
resource partitioning. This
is where species develop
a different niche to get
the same food.
• In this picture birds get
the same insects from
different parts of the tree;
which limits competition.
Assignment
• Check and Reflect in your notes package
1.3
Variation Within Species.
Variation Within Species.
• So far we have learned that the sustainability of
life relies on diversity in
– Ecosystems (types of places to live)
– Communities (types of animals)
– Population (Individuals)
• Healthy populations have a variety of
individuals, which comes from it’s genes.
Differences within populations comes from
genetic diversity- our different genes.
• This type of variation is called variability.
Variability & Survival
• Healthy ecosystems have a lot of genetic
diversity within species.
• Look at the human species.
• What might happen to the Polar bear, if the polar
ice cap melts?
• Environmental changes can make a species go
extinct if there is not enough variablity.
– Toxins, elimination of a food source, change in habitat
can affect the survival of a species.
Example
• Some foxes are born
black.
• It makes it easy to spot in
fields and woods to
predators like the Lynx
and Wolf.
• But in a habitat with black
rocks and soil, it is better
hidden than the normal
red fox.
Variability and Bugs
• Bacteria multiply trillions of
times during an infection.
Usually antibiotics kill all
bacteria, but thanks to
variability some that are
different survive and
reproduce. This means they
become resistant to the
antibiotics.
• They are called superbugs.
Natural Selection.
• Natural selection occurs when the
environment “selects” which individuals
will survive and which will die.
• Some individuals are born ready to survive
in an environment while others are not.
Natural Selection
The Dakota Sparrow.
• The sparrow was able
to survive because of
its variability.
• Some sparrows were fat
and had large energy
reserves, while others
were skinny.
• The fat sparrows were
able to survive while
the skinny sparrows
perished in the cold.
The Giraffe
• Some giraffes had longer necks than
others
• Over time, those with longer necks
could eat more foliage, which made
them more able to reproduce (there
was more energy available to do so)
The Peppered Moth
• Most peppered moths
are born grey, but some
are black.
• Tree bark is grey-ish.
• During the industrial
revolution of Europe,
the trees were covered
in black soot from
burning coal.
• What would have
happened to the moth?
Why?
Foxes
• Predict where these foxes are best
adapted to live? Give reasons.
Why is Natural Selection
important?
https://www.youtube.com/watch?v=0SCjhI86
grU
• Over (long, long, long, long periods of)
time, natural selection allows for evolution
Check and Reflect (24)
1.
2.
3.
4.
5.
What is variability?
In your own words define natural selection?
Describe an example of change in the environment (food,
ecosystem) that might select some individuals in a species
for survival over others. Explain.
Describe an example where variability within a species has
helped a species to survive an environmental change.
Suppose a population of sparrows migrating south for the
winter is blown off course by a storm and the sparrows
become isolated on an island. The only food source
available on the island is a plant that produces large seeds.
Predict which birds in the population, those with large beaks
or those with small beaks, will survive to continue their
migration or to populate the island. Explain your answer.