Earth Changes Over Time Flashcards
Define evolution
Evolution is a gradual change over time.
Name three ways the Earth has evolved…
- climate change
- supercontinents breaking apart
- changes in humans
- changes in plant life
- animal evolution
Whose theory is a theory of acquired traits?
Lamarck
Whose theory is known as the survival of the fittest?
Darwin
Explain Lamarck’s theory as it relates to giraffes…
Lamarck believes that giraffes’ necks have become longer over time because the giraffes have stretched their necks. And the characteristic was then passed onto the offspring (acquired trait).
Explain Darwin’s theory as it relates to giraffes…
- Darwin says that there are short and long neck giraffes due to natural selection and variation.
- Giraffes with short necks were not able to reach food, so they died taking the gene for short necks with them.
- Long-necked giraffes were able to reach the food and survive so there were mainly long-necked giraffes that survived and reproduced (survival of the fittest).
Whose theory believed that animals could go extinct?
Darwin
Whose theory believed that inherited and acquired traits could be passed to offspring?
Lamarck
Whose theory believed that only inherited traits could be passed to offspring?
Darwin
Whose theory thought that organisms could choose their traits and choose to survive?
Lamarck
Whose theory knew that certain traits helped organisms survive better, but that the organisms themselves did not choose their specific traits?
Darwin
Whose theory believed that there was variation in a population?
Darwin
Name three points of evidence that Darwin’s theory is correct…
- Acquired traits are not passed onto offspring; only traits encoded in DNA are passed onto offspring
- Fossil evidence has showed that entire populations have gone extinct
- Mendel’s work of genetics helped to prove Darwin’s theory about traits and DNA
- you could also discuss embryology, homologous & vestigial structures, and geographic distribution
What does “survival of the fittest” mean?
Organisms with specific traits that will be successful for a particular environment will survive the best.
What did Darwin discover about the finches on the Galapagos Islands?
Darwin discovered that the finches were all related but that their beak shape was different due to the different types of food found on the island (adaptions).
What are structural adaptations? Give two examples.
Structural adaptations are the physical features of an organism
Examples - claws, wings, beaks, fur, sharp teeth, etc…
What are behavioral adaptations? Give two examples.
Behavioral adaptations are something that an organism does
Examples
- migrating (birds fly south in winter)
- hiberation (bears in winter)
- octopus squirting ink to get away from a predator
- a sea cucumber throwing out its intestines to scare away an organism
Define speciation
Formation of a new species
Which speciation type has occurred when species mate at different times of the year?
Temporal Isolation
Which speciation type has occurred when two populations are capable of breeding, but they do not due to differences in behavior and courtship rituals?
Behavioral Isolation
Which type of speciation has occurred when two populations are separated by barriers such as mountains or rivers?
Geographic Isolation
Which type of speciation has occurred when species live in the same region but occupy different habitats?
Ecological Isolation
New species form… is this microevolution or macroevolution?
Macroevolution
Which type of speciation has occurred when species cannot breed successfully due to differences in DNA and genetics?
Reproductive Isolation