The Fossil Record
What does the fossil record document about life on Earth?
What is evolution, diversity, extinctions, environments, and the ages of life-forms?
Name the type of fossil that includes footprints and burrows.
What are trace fossils?
What body structures did the fish-to-tetrapod transition transform?
What is the tetrapod body structure?
Name the three main sections of bone arrangement in tetrapod limbs.
What is one large bone → two bones → many small bones?
In rock layers, which layer is older—the bottom or the top?
What is the bottom layer?
Name three types of fossils found in mud or rock.
What are leaf imprints, body fossils, and trace fossils?
Which body parts are most commonly preserved as fossils and why?
What are bones, teeth, shells, and exoskeletons because they resist decay?
Approximately how many million years ago did fins evolve into hands?
What is roughly 390–360 million years ago?
List three bones found in both fossil and modern tetrapod limbs.
What are humerus, radius, ulna, carpals, metacarpals, and phalanges? (Accept any three)
What does the principle of superposition state about sediment layers?
What is that the first sediment layer deposited is at the bottom, making it the oldest?
Why is the fossil record NOT a complete record of every organism?
What are: (1) not every organism becomes a fossil, (2) there were times fossils didn't form, and (3) there are fossils we still haven't found?
What is petrified wood an example of?
What is a woody tissue fossil formed by mineral replacement?
Name the key intermediate fossil that shows limbs with wrist-like joints.
What is Tiktaalik?
What do homologous structures in fossils prove about tetrapods?
What is that all tetrapods descended from a common fish ancestor?
According to the fossil record, what appeared first—organisms with shells or tetrapods?
What are organisms with shells (mollusks and arthropods)?
What is the time period covered by the fossil record?
What is the last 400,000 years?
Name two rare conditions under which soft tissue can be preserved.
What are rapid burial in oxygen-free environments, freezing in permafrost, or trapping in tar pits?
What was the original purpose of the wrist-like joints in Tiktaalik's limbs?
What is pushing off the bottom of shallow water?
Name three different ways modern tetrapods have adapted their limbs.
What is swimming, flying, walking, and grasping?
For how long did fish and organisms with shells live during overlapping time periods?
What is millions of years?
Explain why a fossil's age and the rock layer's age are not always identical.
What is that fossils can be reworked or moved after formation?
What type of fossil is created when insects or plants become trapped in tree resin that hardens over time?
What is amber (or fossilized amber)?
How did fin rays transform into limb bones?
What is through genetic restructuring?
What evidence shows that a bat's wing, a human's arm, and a whale's flipper all evolved from the same ancestor?
What are homologous structures (same bone arrangement and number)?
What does a rock layer provide regarding a fossil's actual age?
What is a minimum age estimate?