Unit One
Biological Diversity
Unit One – Biological Diversity
Topic One – Biological Diversity and Survival
http://taggalaxy.com/
Biology is the study of living things (plants, animals, bacteria, fungus)
Diversity refers to the number of differences between
objects
Therefore, Biological Diversity is the study of the differences
between all living things on the planet
-in almost all animals and plants, there is a
wide variety of differences we can see
-these differences are known as VARIATIONS
-Variations
are found in ALL groups of
living things!
What are some
variations
between students
in our class??
So what’s the point? Why is variation important?
-Biological Diversity looks at the
variation within species
(genetic diversity)….
…the variation between species….
..and the variations of ecosystems.
The greater the amount of
variations, the greater the
diversity!!
The more diversity, the greater the
chance for making new discoveries!
For example, many of our medicine comes from the
different variety of trees.
The Pacific Yew tree found in B.C. makes a cancerfighting chemical called Taxol
As animals and plants become extinct, then
the diversity of life on our planet decreases.
As rain forests get cut down, we lose species of
trees that may have medical value that may
help save lives.
Fact: In the Amazon Rain Forests, biologists have only studied
five percent of the plants that exist there for medical treatment.
Fact: Up to 70% of all the plants that have been studied in the
rainforest have cancer-fighting properties
Fact: In the last 50 years, half of the world’s rain forests have
been wiped out.
Variations For Survival
ADAPTATIONS are features that increase an
organism’s chances of surviving and
reproducing in a particular environment
Animals that live in similar environments
have similar adaptations.
What are adaptations of
animals that live in the water??
Adaptations include two things:
1. Structural Adaptations: physical features
that help an organism to survive in its
environment
a. Fins are used by marine life for mobility.
b. Fur allows animals to retain body heat
during cold conditions.
c. Animals use color to help blend into their surroundings for
protection and to hunt prey.
Munching on a plant
stem in Costa Rica's
Monteverde Cloud Forest
Reserve, this Xylophanes
caterpillar has such tiny
eyes that you would need
a hand lens to see them.
The red "eyes" and
pointed "stinger" are both
fake.
octopus.mpeg
http://www.youtube.com/watch?v=ygh1-ul6E94 Octopus mimicry
2. Behavioural Adaptation:
-how an animal acts
-can be taught how to act by their parents or they are born
with the knowledge (instinct)
a. The migration of birds and whales.
b. Birds dancing to attract a mate.
c. Humans using sounds to
communicate information.
http://www.youtube.com/watch?v=4Mb0GOITRUU&safety_mode=true&persist_safety_m
ode=1 Cuckoo bird clip
So, what’s the big deal about
diversity then?
The larger the variation between animals, the greater the
chances of organisms surviving if their environment
changes or their food source runs out.
E.g. During the ice age, animals that had more fur or could
eat a variety of food sources survived.
Organisms that are not adapted to their
environment or are weak, die off leaving the
strong or best-fitted to their environment to
survive.
Variation Within Species
-a group of organisms are classified as a SPECIES if:
1. They are similar in appearance to other of its kind.
2. They are able to mate in nature with each other and
their offspring are able to breed.
E.g. Grizzly bears are a
species because they have a
distinct look and mate with
other grizzly bears. Their
offspring can also give
birth.
While they often look the same, there is great
variety within a species.
Some are bigger than others, some are faster, some
have larger teeth, some are smarter, some are
different colors
These differences between
animals within the same
species allows for even
greater diversity and
allows individual animals
to be different.
Just because animals look similar to one another,
doesn’t mean they are part of the same species.
MULE!! Cannot have living offspring so it is not a species.
Liger
Tigon
–lion father / tiger mother
–tiger father / lion mother
Variation Among Species
Lynx, Bobcats, and Cougars look similar but all are
difference species.
All are thought to have developed from a common ancestor
but over time, the cats evolved to fit into there own
environment and food sources.
This process of a new species being
formed after many generations is
called SPECIATION.
(SPEE – SEE – AI –SHON)
Members of the
same species
often adapt for
life in a more
specialized
environment
creating sub
species. This
reduces the
competition
between
individuals.
Niche
A niche is the series of roles an organism plays in its
environment.
What is your niche?
The general niches occupied by organisms are:
1. Producer--photosynthetic organisms which
grow using energy from the sun
2. Consumer—eat other organisms for nutrients
a. Herbivore—eats producers
b. Omnivore—eat consumers and producers
c. Carnivore—eat other consumers
Decomposer—breaks down dead organisms and
releases nutrients which are used by other living
things
Broad Niche Organisms AKA Generalists
•Organisms have more general adaptations suited to a
greater variety of habitats and food sources
•These organisms often found in large populations
•Not as many different species found in the regions
inhabited by generalists
•Often located in regions with diverse seasonal changes
Narrow Niche Organisms AKA Specialists
•Organisms have more specialized adaptations suited
to a specific habitat and food source
•These organisms often found in relatively small
populations
•Many specialists located in a single area
What are the advantages and disadvantages
of being a specialist and a generalist?
Symbiotic Relationships
Symbiosis: A close relationship in which two species live
closely together in a relationship that lasts over time.
What is the meaning of these pictures?
Mutualism
Parasitism
Commensalism
both organisms benefit one organism benefits one organism benefits
but the other organism but the other organism
is harmed
is unaffected
Example:
The yucca plant and
the yucca moth
(obligate symbiants)
-- The Yucca moth
eats only yucca plant
pollen and the yucca
plant is only pollinated
by the yucca moth!
Example:
A tapeworm in a cat-The tapeworm robs
the cat of its nutrients
and the worm thrives
while the cat suffers.
Ectoparasites live on
the host.
Endoparasites live in
the host.
Example:
An orchid growing on
a tree--The tree
provides a place for
the orchid to grow so
the orchid benefits.
The orchid does not
harm the tree so the
tree is essentially
unaffected.
What are other examples of symbiosis?
Parasitism
Endoparasites
Dog heart infected with parasitic
heartworms.
Worms
Teeth
(hooks)
worm
worm
Blood
cell
Ectoparasites
Fleas
Ticks
Lice
Commensalism
Mutualism