2. zVariation: The differences found within a species
Variation is important because it is directly related to
adaptability: the specie's ability to adapt/respond to
changes in it's habitat or ecosystem.
4. zVariation: The differences found within a species
Examples of variation within homo sapiens:
• blood type (A, B, AB, or O; positive or negative)
• eye colour
• height
• taste bud concentration
5. zAdaptations
How do living things meet their needs to survive? ...
They adapt!
Organisms "respond" to their environment:
• Organisms which are best suited will survive and
produce offspring
• over time successful characteristics will be more
common therefore the species will have adapted to
their environment
6. z
Structural Adaptations:
Physical features of an organism like the bill on a bird
or the fur on a bear.
Behavioural Adaptations:
The ways organisms "act" to survive. For example, bird
calls and migration are behavioural adaptations.
7. zList 3 examples of each kind of adaptation
Structural:
• Webbed feet
• Bird beaks
• Fur (winter/summer coats)
Behavioural:
• Hibernation
• Migration
• Instincts
8. z Earth Will Be No More
In an attempt to save the human ​population, classrooms
of students ​have been placed aboard rocket ships ​and
are being sent to various planets in ​various galaxies.
This class has been ​sent to IMAGINTHIS, a new planet
with unknown dangers.
9. zYou have arrived. Please stand up
All the initial tests show that it appears ​to be a planet
that humans can inhabit
The atmosphere is 50% oxygen.
Anyone who cannot breathe oxygen: sit down you have
died.
10. z
There appear to be no animals to serve as food for
humans but there are plenty of nuts.
Anyone who cannot survive on nuts alone: sit down you
have died.
11. z
There is some sort of unusual radiation on the planet
that seems to affect anyone with blue eyes. ​They
develop debilitating headaches and eventually die.
All blue eyed people grab your heads and cry out in
pain and sit down: you have died.
12. z
There are these incredible large flying eagle like birds
with a wing span of 13 meters. They are silent in
flight and seem to quickly pick off ​blond or black
haired humans but brown haired individuals are left
alone.
All blond or black haired people are dead : sit down.
13. z
The survivors will continue to live ​happily on the
planet.
You have just participated in a simulation of natural
selection.
When there is a change in the environment: the
organisms of the species that survive are the ones
that will continue that species.
14. z
The survivors will continue to live ​happily on the
planet.
You have just participated in a simulation of natural
selection.
When there is a change in the environment: the
organisms of the species that survive are the ones
that will continue that species.
15. zNatural Selection: Natural Selection occurs when a
particular organism reproduces more than another
because of differences between those organisms,
giving the appearance that one organisms has been
"selected" over another.
Coined by Charles Darwin and Alfred Wallace.
16. zDarwin also coined the phrase: "Survival of the Fittest"
which refers to the fact that the organisms which best
fits it's current situation will have advantages over other
organisms which will allow it to survive better/longer.
"Survival of the Fittest" does not mean survival of the
strongest.
Coined by Charles Darwin and Alfred Wallace.
17. z
On his visit to the Galapagos Islands, Charles Darwin
discovered several species of finches that varied from
island to island, which helped him to develop his theory
of natural selection.
18. z
Example:
The Cliff Swallows of Nebraska - In 1996: Although equally healthy, a
severe cold spell killed 70% of the population (hundreds of thousands).
Scientists that had been studying the population collected over 1856 of
the dead birds. Through careful observation, they found that the birds
that survived had larger bodies and a shorter wingspan (11% shorter)
than the ones that died.
19. z
Example:
Like many animals that evolved in isolation from significant predators, the
dodo was entirely fearless of humans. This fearlessness and its inability
to fly made the dodo easy prey for sailors. Also, sailors introduced dogs,
pigs, cats, rats, and crab-eating macaques, which plundered dodo nests
and competed for the limited food resources. At the same time, humans
destroyed the forest habitat of the dodos. The impact of the introduced
animals on the dodo population, especially the pigs and macaques, led to
the extinction of the Dodo in 1662.
21. z
Discrete Variation
Differences in characteristics ​that have a defined form.
binary: on or off; yes or no
no in-between.
Continuous Variation
Differences in characteristics ​that have a
range/spectrum of forms.
height in adults range from ​1.2m to 2.1m
22. z
Discrete Variation
Examples:
• eye color
• blood type
• albino
• hitchhiker’s thumb
• widow’s peak
Continuous Variation
Examples:
• height
• weight
• pigmentation of skin
• intelligence
• size of hand span