Unit 9 Biology Final-All Units

What did Aristotle believe?

Aristotle believed species were fixed creations arranged by their complexity.

Example of Aristotle’s theory

(Example- earthworms less complex than snakes) ⚫ Idea lasted approximately 2000 years

Who was Carolus Linnaeus?

-first to group similar organisms

-Developed two word name(Genus Species)

-Known as binomial nomenclature

What is an example of Carolus Linnaeus’s two word name?

Humans=Homo Sapiens

What did Charles Lyell do?

-Created Proposed Theory of Uniformitarianism

-One of the first to propose that the Earth was millions of years old.

Who created the Principles of Geology and what was it about?

Principles of Geology was created by Charles Lyell and it…

-explained the geological processes that shaped the Earth.

-Helped Darwin understand why past organisms were at high elevations.

-Expanded Earth’s age(Dated it as older than previously thought)

Who was Jean-Baptiste Lamarck and what did he do?

-Stated that changes are adaptations to environment acquired in an organism’s lifetime.(Incorrect)

-Proposes these changes were passed to offspring.

What is Lamarck’s idea of Evolution?

**Lamarck did NOT know how traits are inherited

Law of Use and Disuse

-If a body part were used, it got stronger

-If a body part was not used, it deteriorated

-Use & Disuse - organisms could change the size or shape of organs by using them or not using them

What did Thomas Malthus do?

Population Growth-Population size i’d limited by resources such as the food supply.

-Plants & animals produce far more offspring than can be supported.

-Most offspring die; otherwise the earth would be overpopulated.

The Voyage of the Beagle

The HMS Beagle sailed from

England on December 27 th ,

1831

The Beagle arrived at

the Galapagos islands

on September 15 th ,

1835.

Why were finches important in Darwin’s studies?

Darwin concluded that one type of finch from South America had arrived on the recently-risen islands and, like the tortoises, had adapted to the different opportunities found on each island. Darwin believed that their creation was not a single event, but a process of many changes, from one form, into many different ones.

What were Darwin’s observations?

-Left unchecked, the number of organisms of each species will increase exponentially, generation to generation.

-Each Individual has their own unique variations even within the same species

-Survival-Only those who are bets suite for the environment will survive and typically those who survive have adaptation better suite for the environment.

What is the definition of natural selection?

Individuals that have better physical or behavioral trait that suit their environment are more likely to survive and reproduce rather than those who do not.

So what is Evolution?

Evolutions occurs over a population’s genes and frequencies change over time.

What causes genetic change in populations?

-Mutations

-Environmental changes

-Genetic drift

-Gene Flow

What is Reproductive Isolation?

When populations cant breed due to geographic separation

What is Gradualism?

Gradual change in an environment over a long period of time leading to new species

What is an adaptation?

An adaptation is an inherited characteristic that increases an organism’s chance for survival. Adaptations can be both behavioral and physical.If the adaptations are favorable, they become more common in a population.

What is mimicry and camouflage?

Mimicry-When one species is able to resemble another.

Camouflage-Resembling surroundings

Important notes about Natural Selection!

-If a species cannot adapt, it will likely not survive.

-An individual CANNOT change during its lifetime; it can however pass changes (mutations within sex cells) onto its offspring.

-Natural selection does not “give” organisms what they need; it is a long process that favors certain variations. Individuals without these variations perish.

-The driving mechanism behind the process of natural selection is genetic variation.

What is natural variation and artificial selection?

Natural variation-Differences among a trait within individuals of a species.

Artificial selection-Selective breeding to enhance desired traits among livestock or crops

What was the Missing Link?

-In Darwin’s time, there was no mechanism to explain natural selection.

-Mendel’s work provided the missing Link in evolutionary theory.

What is Common descent with Modification?

-Darwin proposed that organisms descended from common ancestors.

-These changes could lead to a divergence from a common form producing new species.

Does Descent with Modification take a long time and what changes can be observed?

-Takes place over a long period of time

Changes

-Body structures

-Ecological niches

-Habitats

-Behaviors

Do species just randomly appear or do they come from different species?

Each living species has descended with changes from other species over time.

What is Speciation?

-The formation of a new species=speciation.

-Divergence is the driving force behind speciation.

-Species can have subspecies

What are subspecies?

Members of the same species that differ genetically.

What are the Two models of Evolution?

Gradualism-Gradual change that occurs over a long period of time.

Punctuated equilibrium-Rapid change in species are separated by periods of little or no change.

What is Macroevolution and microevolution?

Macroevolution-Long time scale events that create and destroy species.

Microevolution-Short time scale events that change the genes of populations

What are Biological Molecules?

Similarities in DNA sequences can determine common ancestry

What are homologous Body Structures?

Related structures that are inherited from a common ancestor. Structures have similar structure but develop different functions.

-Arms,Wings,legs,Flippers(different species but same function or form)

What are vestigial structures?

Structures that are present in an organism, but serve no apparent purpose.

Ex-Appendix in man,legs on snakes,and pelvic bones on whales.

Similarities In early development

Embryonic structures of different species show significant similarities

What is the fossil Record?

Embryonic structures of different species show significant similarities