What can be deduced about dinosaur extinction from the K-Pg boundary sequence?
What will be an ideal response?
Several clues are provided from the K-Pg boundary sequence about dinosaur extinction.
1 . Many dinosaur fossils can be found beneath this layer but no dinosaur fossils are found above it. This suggests that dinosaurs became extinct from this event.
2 . The content of the K-Pg boundary suggests a meteorite impact. It consists of unusual clay rich in iridium, an element much more abundant in asteroids than in Earth's crust. It also contains shocked quartz and small glass spheres called tektites. These minerals form when quartz or sand undergoes a sudden, violent application of extreme pressure. The only processes on Earth that produce these minerals are atomic bomb explosions and meteorite impacts. And of course, atomic bombs did not exist then.
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Why can't "scientific creationism" be considered a science? Check all that apply.
_____ It is not supported by any empirical observations. _____ It does not obtain its principles from observation, as does science. _____ Its assumptions lead to no hypotheses that could be tested and possibly disproved. _____ The idea of creation by a supernatural agency lies outside the realm of science. _____ Only non-scientists believe it.
Examine the flux diagrams in Figure 25.6 to address the following questions. At what rate does fossil fuel combustion contribute carbon to the atmosphere?
What will be an ideal response?
_______ Isolation occurs when two species occupy different habitats within the same geographical range.
Fill in the blank(s) with the appropriate word(s).
The cell's energy is produced by the ___.
What will be an ideal response?