1. Evolution is not the only theory

2. But it is the scientifically accepted explanation at this point
There have been multiple theories of evolution over time.
Lamarck & Darwin’s story

3. Lamarck’s story
One of the first scientists to recognize that organisms change over time and that they were somehow adapted to their environments.
Looked at fossils and saw that the youngest ones were most similar to the current organisms
To explain these characteristics

4. Lamarck’s story
Looked at fossils and found that the younger they were, the closer they were to the modern version.
A Desire to Change:
Organisms changed because of a desire to better themselves
Inheritance of acquired characteristics
Modifications that occur during an organism's lifetime are passed on to its offspring
Theory of use and disuse:
Body parts that were used lots became larger and stronger
Ones that were not used slowly disappeared

5. Darwin’s story – the voyage that changed scientific thought
Darwin was educated and had a strong interest in natural history. We also had keen powers of observation and an analytical mind.
During this voyage. Darwin traveled to several continents and many remote islands and wherever he went, he collected specimens.

6. Darwin’s story
He was impressed by the many different ways organisms survive and produce offspring. He realized that most of the animals and plants he encountered had body parts and behaviours that did things very well. – Question: can anyone think of any?
He called this fitness.
He believed that his happened because just as all organisms come from pre-existing organisms, so do species.  if you go back far enough, you can see that all species have shared or common ancestors. This, he referred to as common descent
He also argued that fitness comes from a process called adaptation.
Successful adaptation allows those organisms that are better suited to that environment to survive better and reproduce.
The long necked giraffe had an adaptation that allowed it to eat leaves that were too high for most grazing animals so I was in a better situation to survive and reproduce.

7. speciation
Species: a group of similar-looking organisms that breed with one another and produce fertile offspring in the natural environment
Reproductive isolation: separation of populations so that they can’t interbreed
Natural selection can work differently on each new group
This can happen because of:
Geographic barriers (rivers, mountains, roads…)
Behaviour
Characteristics

8. Over time the theory of evolution evolved

9. We are going to adapt to the environment
Beak Adaptations Activity
Population: a collection of individuals of the same species in a given area whose members can breed with each other.
Environment: an area the organisms inhabit. Contains all of the biotic and abiotic factors associated with the organism.
Competition: is one of many interacting biotic and abiotic factors that affect community structure
Fitness: combination of physical traits and behaviors that help an organism survive and reproduce in its environment.
Adaptation: process that enables organisms o become better suited to their environments.