How Does Biodiversity
Contribute to the survival
of species?
Examining Diversity
A species is a particular group of organisms that
have the same structure and can reproduce with
each other.
Scientists estimate there are between million kinds of
living things living today
Identified species
1.5 million species of animals
species of plants that have been identified by
biologists.
About 1/5 of species are insects
All living things …
are made up of cells
need energy
grow and develop
reproduce
have adaptations which suit them to
the specific habitat in which they live.
Why do so many different types of
organisms exist on Earth today?
Biological Diversity
Refers to all the different types of organisms on
Earth.
There are so many living things, that scientists
need to examine them in smaller groups
Measuring Biodiversity
Biological diversity is the
number and variety of
organisms in an area
Biologists use the Diversity
index to measure
biological diversity
Diversity Index = number of
runs / total number of
plants
How do we classify living things?
The two-name Latin naming system for all living
things was developed by Carolus Linnaeus in the
18th century, enabling scientists, around the
world, to refer to the same species, by the same
name.
This classification system was much more reliable
than previous systems, because he used structure,
rather than habitat.
Two words identify each organism.
The 1st represents the organisms genus and the
2nd represents the organisms particular species.
There are so many types of organisms, we classify
them into 5 large groups or Kingdoms.
Animal, Plant, Fungi Kingdoms
The 5 kingdom classification system can be
further subdivided, with each sub-division having
its own name.
Kingdom = Animal
phylum = chordata
class = mamalia
order = carnivora
family = canidae
genus = canis
species = familiaris
Diversity between Ecosystems
Ecosystem: The living (biotic) and non-living (abiotic)
factors in an environment.
What are some biotic and abiotic factors in our
school yard?
There are many different ecosystems on Earth (ex.
Boreal forest, prairie, mountains, grasslands, etc.)
Each ecosystem is very different, and these
differences affect the number and type of species
that can live there.
Diversity within Ecosystems
In each ecosystem, there is a wide variety of
different living things.
Living things that share an area and the same
resources form a population.
Different populations of different species live
together in communities.
Diversity within Species
Even within the same species, there is a great
deal of diversity
Look around you, is everyone in the class the
same? Why do you think this is?!
There are subtle variations between
individual members of a population. This is
known as genetic diversity.
These variations between individuals may or
may not be visible (ie. Colour, shape, size,
blood type, etc)
Some insects have different forms t do different
jobs - Polymorphism
Worker bees and queen
Termite queen and soldier
Metamorphism
Some organisms have huge variation between
males and
females – Sexual Dimorphism
Variation within Species
Cardinal
How are species distributed?
There are areas of our planet that have a high
number of different species, and some areas that
have very few?
Why do you think this might be?
Where do you think the greatest diversity might be?
Lowest?
Niches
A niche is the role of an organism within a
particular ecosystem.
An organism's niche includes:
What it eats
What eats it
Its habitat
Nesting site, range and habits
What effect it has on the other populations
What effect it has on the environment
Broad and Narrow Niche
 In northern Canada there are large populations of those
species found there, but there are not many different plant
and animal species.
 Canis lupus, Ursus maritimus
 Organisms living in this ecosystem have a broad niche with
adaptations that enable them to survive the extreme changes
occurring there. These species are considered to be generalists
– able to spread over large areas.
Broad and Narrow Niche
In contrast, hundreds of thousands of species (in
small populations) can be found in the rainforests
of Central and South America. Narrow niche –
specialists. Generalists- wide area low numbers
Specialists- well adapted to specific
environments
Symbiosis
is a close relationship between two or more
different species
Sym = together
Bios = life
3 Types of Symbiotic Relationships:
Mutualism
Commensalism
Parasitism
Mutualism (+, +)
When both species in the relationship benefit, it is
called mutualism.
The honey bee and the flower. The honeybee obtains
nectar and the flower becomes pollinated.
Commensalism (+, 0)
One of the species benefit and the other does not, it
is called commensalism.
Sea birds exhibiting commensalism with a humpback
whale. As the whale feeds, it brings a number of small
fish to the surface and stuns a number of these. This
picture shows how the birds benefit from the whale's
efforts without affecting the whale in any way
Arasitism (+,-)
A symbiotic relationship where one species benefits
and the other species is harmed is called parasitism.
A tapeworm in a fish’s gut obtains the nutrients but
may eventually kill the fish by depriving it of nutrients
Try This!
Barnacles are organisms that attach themselves
to whales to move throughout the different parts
of the ocean. They benefit from their relationship
with the whales, but the whales are not harmed,
nor do they benefit. This type of symbiotic
relationship is called …
A. mutualism
B. mycorrhizae
C. parasitism
D. commensalism
What if no one benefits?
 Interspecies competition happens when two or more species
need the same resource.
 If this happens, for example 2 species compete for the same
food, there is less of it for each species
 This can lead to more deaths due to starvation – limiting the
size of each population
 This is why each organism needs a niche (remember, a niche
is an organisms role)
 The niche of a population in one area might be different from
their niche in a different area due to food and competition
 Sometimes, species can divide a resource up so they can all
use it – called resource partitioning
Variation Within Species
 Individuals in a species can adapt to different situations
 Behavioural adaptations are the behavioural changes
of a species that makes the species better able to
reproduce and survive.
 Behavioural changes include: mating, migrating, and
sleep patterns.
 Some adaptations are structural. Structural adaptations
are physical features of an organism that make the
species better able to reproduce and survive.
Variability and Survival
A healthy ecosystem has a great deal of
genetic diversity among the species that inhabit
them.
Variability is essential for species survival. If the
environment changes the species with a great
deal of variation is more likely to survive.
Species that are different are more able to resist:
disease, new predator, toxic substances,
elimination of a food source.
What did Darwin’s Travels reveal
The diversity of living species was far greater
than anyone had previously known!!
These observations led him to develop the
theory of evolution!!