Fossil Record
When a fossil disappears in the fossil record......
Extinction/Extinct
this event causes a SMALL number of species to go extinct, usually through speciation
mountain building, rift valley
fossils are ___________ of _____________ life.
Evidence, past
what is absolute dating?
Using radiometric dating to get an approximate year of rock/fossil
This occurs after mass extinctions
rapid speciation
The fossil record shows us that speciation occurs over ____________ generations
many
This event causes only ash to go into sky
meteor impact
Trace fossil
What is relative dating?
comparing rock layers, old vs new
rapid burial
What could you infer happened when you see many fossils disappear completely in one rock layer? .... the main cause of this disappearance
climate change.... mass extinction
This event causes ash and gas to go into sky
volcano
This type of fossil is helpful in relative dating rocks
index fossil
which law states the newer fossils are at the top?
law of superposition
if we see the same species in two different places, but in the same time frame, what can we infer those two places?
Why couldn't a hurricane cause a mass extinction?
doesn't happen on a global scale
how can a volcano or meteor impact impact the amount of oxygen in the air?
less photosynthesis from blocked out sun
What is one way the entire animal can be preserved?
Ice, Sap(resin)
Where would the least complex fossils be found in an outcrop?
near the bottom
How do we know that dinosaurs laid eggs when they have been dead for 65 million years?
We can compare them to modern day reptiles and birds which also lay eggs.
If an outcrop shows sea creatures, then a layer of land creatures, what does this tell us?
Climate change or Environmental Change
Which event would cause evidence of lowering sea levels and climate chance, which we can see in a rock outcrop?
Ice Age
Compare their bone structures
What causes an outcrop to not have fossils in the correct order/missing fossils?
Unconformity, erosion, etc. Disturbed rocks.
What helps make an ecosystem sustainable?
diverse species within the ecosystem