Chapter 14-Darwin and Evolution (Test)

who was Darwin

English student of nature and collected insects, loved geology and bio

Age Darwin went on HMS Beagle

22, was naturaliston a voyage that lasted nearly five years.

what did he observe

species variation and geological formations that led him to propose new mechanism by which species arise and change (evolution)

before Darwin what did the people think of Earth

that it was only few thousand years old and species stayed the same

George Cuvier

father of paleontology, he thought natural catastrophes caused certain species to go extinct and others took their place

Jean Baptiste Lamarck

Proposed inheritance of acquired characteristics, suggesting that organisms can pass on traits acquired during their lifetime.

Darwins conclusions

organisms are related through common descent, adaptation to environments results in diversity based on fossils, biological, and geographical evidence.

Biogeography

the study of the distribution of organisms across different geographical areas and how it relates to evolution and environmental factors.

Covergent evolution

the process where unrelated organisms develop similar traits due to adapting to similar environments or ecological niches.

how is earth subject to change

Slow and continuous

Cycle of erosion and uplift

What did Darwin find in Argentina

Raised beaches on coastlines

Darwin and Chile

Found earthquake took marine shells high in the cliff of the Andes Mountains

Endemic

Organism not found anywhere else on earth

Ground dwelling finch beak

Depends on the size of the seeds they eat

Tree dwelling finch beak

Determined by size of insect

Adaptation

Characteristic that makes an organism suited to its environment

Natural selection

Mechanism of evolutionary change that requires

Member so population have heritable variation

Population has more kids than the resources in the environment

Those with favorable traits survive and reproduce

Over time the part of favorable trait increases in population and becomes adapted

What determines the phenotype of organism

Genes and environment

Thomas Malthus

Said that death and famine were inevitable because humans reproduce more than we can make our food

What drives the struggle for existence

Competition

Fitness

Reproduction success of an individual related to other members of population

Who are the most fit organisms

Those who are better at surviving gathering more food mates and then reproducing

Why does fitness vary

Because organisms vary anatomically and physiologically and the envío produces challenge to survive

What are the 4 pieces of evidence that support evolution theory

Fossil evidence

Anatomical

Biogeographical

Molecular

Evolutionary theory

All organisms have common ancestor but each has adapted to its environment by natural selection

Fossil evidence trapped in rock strata

Fossils trapped in rock

Clear line of succession simple to complex

Fossils act as intermediaries

Biogeographical evidence

When related they evolve in one are and then spread to other regions

Vestigial structure

Anatomical features that are fully developed in one gruoup but reduced and no function in other similar

Ex- penguins don’t use wings to fly

Homologous structure

Anatomically similar structures explained by common ancestor

Ex- mammals and their bones

Molecular evidence

All living organisms use basic biological molecules DNA ATP and many or similar enzymes

Where does diversity come from

Slight difference in same genes