Evolution & Natural Selection Flashcards
What is the principle of fossil succession?
Fossils in the rock record follow a specific order
What is the idea of evolution?
That life changes and adapts to its surroundings over time
Adaptations suit the time and environment
Is there a direction or goal for evolution? Yes or no?
No, since animals just change over time to meet the demands of the ever-changing world around them
Is there only one solution to a problem in regard to evolution?
For the most part, often yes, there is only one solution to a problem
Who was Jean-Baptiste Lamarck? (1744-1829)
He considered that traits acquired in life would be passed down to offspring
He was in fact wrong since acquired traits are not inherited
Who was Charles Darwin?
The first to create a comprehensive model for evolution/how animals change
What do we call Charles Darwin’s model of evolution?
“Evolution through natural selection” or “Darwinism”
What did Darwin find?
The traits that allow you to survive and reproduce will be present in later generations
If you can’t survive, you can’t reproduce
Where did Darwin get his idea of natural selection from?
By the artificial selection of animals, since we are able to select and breed them for specific traits
Ex. Dogs since their original ancestors all came from the Wild Gray Wolf
What is natural slection?
Animals becoming adapted to their surrounding environment
They will change over time to survive
Ex. ancestors of the WHALE were once land dwellers but changed over time to be built for the deep water
What are the 2 major components of natural slection?
1) The creation of variation within a population
2) The selection of favorable characteristics
that allow for survival and the passing of genes
What is the most common source of variation?
Genetic Mutations
What are genetic mutations? How do they usually occur?
Mistakes that occur in the DNA
Usually occur when there is a copy error during the replication of DNA
Can have significant changes of something over many generations
Whats the commonality of most mutations?
NOT NECESSARILY BENEFICIAL, can linger in populations if not deadly
Ex. Heterochromia (Diff Eye colors)
What happens to mutations that are immediately deadly or seriously debilitating?
They will disappear quickly since the mutation will cause the host to die
Ex. Sickle Cell Anemia
