Creation of Earth
What is the name of the hypothesis that scientists developed to explain how our solar system formed?
______________ hypothesis
Nebular Hypothesis
How long ago did earth form?
4.5 billion years ago
Oldest on bottom, newest on top
What are the two types of dating?
Absolute and Relative
Riverbluff cave is known for being the oldest ______________________________
Oldest ice age cave in north america
A nebula is a massive cloud of : ______________ and ____________
dust and gas
What was the main source of gases that produced our first atmosphere?
Volcanoes
What are the divisions of geologic time and what is the correct order? From largest chunk of time to smallest
Eon, Era, Period, Epoch
How do scientists use rock layers to date a rock/fossil?
It tells us if the rock or fossil that has been found is older/newer than the rock around it based on its position AND what other life forms may have been around during that time (fossils found in the same layer).
How was the cave discovered?
Discovered by chance on 9/11 when construction workers set off explosives to build a road and blasted a hole- creating an entrance to the cave.
Material within the nebula is able to collect and form together due to ___________________.
gravity
What organism was first responsible for contributing large amounts of oxygen to our atmosphere AND what process did it use?
cyanobacteria (a.k.a blue/green algae)
photosynthesis
No, all different amounts of time. Divided by major events like extinctions
It must be preserved well enough over time (prevented from decaying) and then the bone is slowly replaced with mineral. Becomes a rock
Sealed off for 55,000+ years, no traffic in and out of the cave that would have caused things to be crushed/destroyed. No air flow to bring in pollutants. Moisture was trapped, everything stayed wet (mud) and allowed things to decompose so slowly that it was able to preserve
Before the current hypothesis, people believed our sun and planets formed (choose one): at the same time or separately
With the current hypothesis, scientists understand that our sun and planets formed (choose one): at the same time or separately
Before: separately
Current: at the same time
How did Earth's moon form?
A small planet named Theia collided with Earth- the debris collected into the moon and began to orbit Earth
What do we call the time that occupied the majority (88%) of Earth's history and what was it like?
Pre-cambrian time
Ancient earth, still cooling down/stabilizing and no life
What is special about an index fossil?
It is like a bookmark for scientists studying the particular layer it is found in. It is abundant, widespread, and short lived- ONLY found in that layer.
What are two animals that may have lived inside the cave?
Peccary, steppe mammoth, wolves, turtle, short faced bear, american lion
What is the difference between solar system and universe?
Universe = all the solar systems, everything in space
What layer needed to form in order for life to expand?
ozone layer
What are the 3 main eras we discussed AND what is one main thing each is known for?
Paleozoic: Ancient life, explosion of life
Mesozoic: middle life, dinosaurs
Cenozoic: recent life, mammals
What is the process for absolute dating called and how is it done?
Radiometric dating- scientists measure how radioactive particles in a rock or fossil decay over time to tell its age. Less radioactive particles = older. More radioactive particles = younger
Name TWO fossils/preservations/pieces of evidence found in the cave AND what was significant about that find/what did it tell us about the cave?
Lots of correct answers
What is the difference between a hypothesis/theory/law AND does one ever become another?
Hypothesis: proposed explanation to an observation that is testable
Theory: explanation of a phenomena in nature that is based in a large body of evidence and facts (tells us WHY something happens)
Law: Rules of nature that tell us WHAT happens and usually based in math
Early earth begins with the planet as a molten body and ends with becoming stable enough to house primitive marine organisms. What is the correct order of steps in between?
A. Oceans form
B. Earth's gravitational pull increases and Earth becomes more dense
C. Rain falls
D. Gases (including water vapor) form the atmosphere
B. Gravitational pull increases, Earth denser
D. Gases and water vapor form the atmosphere
C. Rain falls
A. Oceans form
Name two types of animal that survived the dinosaur extinction/asteroid impact
Therapods (later became birds)
small mammals
The law of ____________ describes how younger layers of rock are found at the __________ and older layers of rock are found at the __________.
Law of superposition- younger rock on top, older rock on bottom
What is one animal at the museum that is being studied/is on display that is NOT from the cave?
Henry the triceratops
Nodosaurus
Assortment of other fossils from different time periods and skulls of recent animals