Transcript Survival of Organisms

Survival of Organisms
Charles Darwin
• Lived in the 1800’s
• Wrote two books:
• The Origin of Species by Means of Natural
Selection and The Descent of Man
• First evolutionary scientist
• Created the idea of natural selection
• Work was controversial then and is still
today
Evolution
Definition:
• Process that results in
changes in a population
over many generations
• Evolution is a result of
natural selection
Microevolution:
• Evolution on a small
scale
• Changes that affect a
population
Macroevolution:
• Evolution on a large scale
• Illustrates the history of
life
Natural selection:
• Process in nature where organisms best adapted to the
environment will survive
• Called the survival of the fittest
What does an organism need to
survive 100 years from now?
• Turn to your partner and make a list
All these things can be grouped into 2
things:
1. Prevent early death
2. Reproduce
What happens if an organism is
unable to survive?
• They will die and eventually become
extinct, which is when an organism’s
species fails to continue.
How can an organism survive?
1. By its physical features
2. By its chemical features
3. By its behaviors
How does an organism get the
characteristics they need to survive?
• Inherited from parents
• Mutations = A change in a chromosome
Some mutations can be beneficial
• The characteristics that
allow an organism to live in
specific environment are
called ADAPTATIONS
– Adaptations are gradual and
occur over several generations
Adaptations
Animal or Plant Adaptations
You and your neighbor…Make a list of as
many different adaptations you can think of
1. Write down the name of the animal/plant
2. Describe its adaptation
(one animal/plant may have more than one
adaptation)
Animal Adaptations
Animal Physical Features
Coloration
• Camouflage
• Mimicry
• Attraction of mates
• Warning coloring
Structures
• Claws
• Spines
• Fur
• Beaks
• And more…
Purpose: To Survive and Reproduce
Capture food
Protection from being eaten
Protection from the environment
Chemical Features
Some animals produce a chemical to increase their
survival
Sometimes the chemical is a toxin = poisonous
chemical
• protects an animal from being eaten
• helps capture their prey
• Attracts mates
Example: Toads, venomous snakes,
skunks
Warm Blooded vs Cold Blooded
Warm Blooded
• Body is kept at a
constant temperature
• Regulated through
homeostasis
– Definition: organisms
ability to maintain
stability
Cold Blooded
• Animal is unable to
regulate their own
body temperature
Plant Adaptations
Plant Features
Physical Features
Thorns
Sticky hairs
Waxy leaves
Leaf Size
Purpose:
–
–
–
–
Protect from predators
Seed dispersal
Prevention of water loss
Pollination
Chemical Features
Odor (foul or sweet)
Distasteful
Irritant
Purpose:
– Toxins keep predators
away
– Attracts insects
(pollination)
Questions to think about….
1. Why would a plant have waxy leaves
and where does it most likely live?
2. Why does a plant have extra large leaves
and where does it most likely live?
3. Why does a plant have tiny leaves and
where does it most likely live?
Specific Plant Characteristics
• Plant reproduction occurs by successful
pollination and seed dispersal
Pollination
• transfer of pollen; must
occur before fertilization
• Adaptations that help:
– Flower color
– Fragrance
Seed Dispersal
• seeds need to be spread
out to new locations
• Seeds are dispersed by
1.
2.
3.
4.
Wind
Water
Animal
Explosion
Behaviors
Animal Behaviors
• Animals have specific behaviors that lead
to their survival
• Behaviors can be…
– Instinctive
– Learned
Instinctive Behavior
• Instinctive Behavior: “INSTINCT”
• Behavior performed without having been taught
through experience
What are some behaviors that are
instinctive?
Migration of birds
Hibernation
Hunting/Foraging
Flying
Swimming
Mating
Migration
• Movement of animals from one area to
another
• Reasons for migration:
1. Climate
2. Mating/Breeding
3. Search of Resources (food, shelter,
water, space, etc)
• Sometimes migration is an instinctive
behavior…
• Birds fly south, salmon swim upstream, etc.
• Sometimes migration is a necessary (forced)
behavior…
• Sometimes animals must migrate to a new area,
or they will die
• Examples: water hole has dried up, competition
for food, natural disaster like a fire
Hibernation
• State of inactivity and decreased metabolic
activity
• Why does an animal hibernate?
Adaptation to climate
Conserve Energy--Lack of food
• Usually occurs during the winter
• Examples
Bears, bats, chipmunks,
raccoon
Inactivity in the Summer
Called… Estivation
• Similar to hibernation, but occurs during
the summer
• Examples: frogs, tortoise
Dormancy of Plants
• A suspension in plant development and
growth
• Hibernation for plants
Why?
• To survive when the climate
is unsuitable for growth
• Too hot or too cold
• Lack of water
Seed Dormancy
• Seeds can be
protected until
conditions are ideal
• Seeds have a hard
seed coat to protect
Tree Dormancy
• Can include losing
leaves and no new
growth