Darwin’s Theory of Darwin’s Theory of EvolutionEvolution

The History of EvolutionThe History of Evolution• Evolution is defined as _________ over timeEvolution is defined as _________ over time

• The theory that all organisms on Earth are The theory that all organisms on Earth are related by __________ __________ and that related by __________ __________ and that they have changed over time (adapted) they have changed over time (adapted) mostly because of __________ __________.mostly because of __________ __________.

• __________ __________ is one of the most __________ __________ is one of the most famous scientists associated with the famous scientists associated with the theory of evolutiontheory of evolution

Darwin’s interestDarwin’s interest• Darwin’s observations and research played Darwin’s observations and research played

an important role in the development of the an important role in the development of the theory of evolution that is still __________ theory of evolution that is still __________ __________ today__________ today

• During his voyage on the U.S.S. Beagle, he During his voyage on the U.S.S. Beagle, he would collect specimens from the different would collect specimens from the different areas he visitedareas he visited

• He was fascinated to see the variety in the He was fascinated to see the variety in the different plants and animals that he studieddifferent plants and animals that he studied

He did notice one He did notice one similarity:similarity:

All of the organisms he observed All of the organisms he observed were well suited (well matched) to were well suited (well matched) to

their _______________their _______________

AdaptationAdaptation• An adaptation is any __________

____________ that increases an organisms chance for __________

• Adaptations can be __________ or __________ and can be passed from generation to generation

• The process of becoming __________ __________ to the environment

Different types of adaptations:Different types of adaptations:

• Genetic adaptation – always genetically controlled (ex: 5 fingers, giraffe’s neck)

Different types of adaptations:Different types of adaptations:• Physiological adaptation – change in the

reactions; can be genetic or not (ex: acclimation to altitude or climate, coat

color change during seasons)

Different types of adaptations:Different types of adaptations:

• Behavioral adaptation – change in behavior; can be genetic or not (ex:

chimps using sticks to catch termites, bears eating garbage)

Survival of the fittestSurvival of the fittest• The ability of an individual to __________ The ability of an individual to __________

and __________ is called __________and __________ is called __________

• Adaptations that help an animal become Adaptations that help an animal become more fit to __________ and __________ more fit to __________ and __________ more ____________ are commonly selectedmore ____________ are commonly selected

• This is known as __________ ___ ___ This is known as __________ ___ ___ ____________________

Over time, natural selection will Over time, natural selection will change the ____________ of a change the ____________ of a population, increasing the population, increasing the

__________ of that population__________ of that population

Survival of the fittest is Survival of the fittest is also known as __________ also known as __________

____________________

Proof? You want proof?Proof? You want proof?• Evidence of evolution through adaptation Evidence of evolution through adaptation

and natural selection can be found in:and natural selection can be found in:

– the __________ __________the __________ __________

– ____________ ____________ (different animals ____________ ____________ (different animals __________ similarly because of the same __________ similarly because of the same _______________ factors)_______________ factors)

– _______________ structures_______________ structures

– Similarities in early development of ___________Similarities in early development of ___________

TODAY…• Evolution is widely accepted by the scientific

community• Theories are constantly changing based on new

evidence (mitochondrial DNA, rapid evolution…)• Evolution is still occurring• Many species are becoming extinct because they

cannot evolve as fast as humans are changing the environment.

• Humans are “meddling” with evolution through artificial selection (fruit, dogs…)