1. 4-10-18 Theory of Evolution by Natural Selection

2. Do Now: Take out your homework. Complete the following:
Use a meter stick to measure the length from your elbow to the tip of your middle finger in centimeters. Record the measurement.
Add your measurement to the class list on the white board.
Organize all of the measurements from shortest to longest.
Break the data into regular increments, such as cm, cm, and cm. Count the number of measurements within each increment.
Construct a bar graph using the data. Label each axis and give our graph a title.
What are the shortest and longest measurements?
How much do the shortest and longest lengths vary from each other? (i.e., what is the range?)
Describe how your results provide evidence of variations within your classroom population.

4. HW Review: Key Concept Builder – How does Darwin’s theory of evolution by natural selection explain how species change over time?
A process by which populations of organisms with variations that help them survive in their environments live longer, compete better, and reproduce.
The characteristics are inherited by the offspring.
A slight difference in the appearance of individual members of a species.

5. HW Review: Key Concept Builder – How does Darwin’s theory of evolution by natural selection explain how species change over time?
They occur naturally in populations as a result of random mutations, or changes in genes.
Helpful variations that help organisms survive are spread throughout the population as the organisms reproduce.
Through natural selection, tortoises, finches, and other diverse species became matched to their food sources.

6. EQ: How are adaptations evidence of natural selection?

7. Adaptations
Through natural selection, a helpful variation in one individual can spread to all members of a population because it allows them to survive their environments.
An adaptation: an inherited trait that increases an organism’s chance of surviving and reproducing in its environment.
Adaptacion: rasgo heredado que aumenta la oportunidad de un organism de sobrevivir y reproducrise en su medioambiente.
Natural Selection

8. Turn & Talk How do variations lead to adaptations?
Beneficial variations spread to entire populations through natural selection and produce adaptations that enable the populations to survive in their environments.

9. Types of Adaptations 3 categories of adaptations:
Structural adaptations involve color, shape, and other physical characteristics.
Ex: the jackrabbit’s powerful legs help it run fast to escape from predators.

10. Types of Adaptations
Behavioral adaptations involve the way an organism behaves or acts.
Ex: the jackrabbit stays still during the hottest part of the day, helping it conserve energy

11. Types of Adaptations
Functional adaptations involve internal body systems that affect biochemistry.
Ex: The blood vessels in the jackrabbit’s ears expand to enable the blood to cool before re-entering the body.

12. Environmental Interactions
Species evolve adaptations as they interact with their environments, which include other species.
Camouflage and mimicry are adaptations that help species avoid being eaten.
Camouflage is an adaptation that enables a species to blend in with its environment.
Camuflaje: adaptacion que permite a las especies mezclarse con su medioambiente.
Ex: the seahorse in the figure is the same color and has a texture similar to the coral it is resting on.
This adaptation makes organisms nearly invisible.

13. Environmental Interactions
Mimicry: an adaptation in which one species looks like another species.
Mimetismo: una adaptacion en el cual una especie se parece a otra especie.
Ex: the caterpillar in the figure resembles a snake. Predators see it and are scared away.
This adaptation draws attention to organisms.

14. Environmental Interactions
Many other adaptations help species eat. The pelican has a beak and mouth uniquely adapted to its food source – fish.

15. Environmental Factors
Species must also adapt to an environment’s nonliving parts, such as temperature, water, nutrients in soil, and climate.
Ex: Deciduous trees shed their leaves due to changes in climate.

16. Adaptations
Living and nonliving factors are always changing. Even slight environmental changes affect how species adapt.
If a species is unable to adapt, it can go extinct.
Ex: increases in sea temperatures have caused coral in the Great Barrier Reef to die.

17. Artificial Selection
selective breeding: the selection and breeding of organisms for desired traits.
Cria selective: seleccion y la cria de organismos para las caracteristicas deseadas
Darwin realized that changes caused by selective breeding were much like changes caused by natural selection.
Instead of nature selecting variations, humans selected them. Darwin called this process artificial selection.
Artificial selection explains and supports Darwin’s theory.