2. Charles Darwin and Alfred Wallace both first proposed
3. Evolution
4. A random change in an organism's DNA is called
5. Populations, not individuals, evolve.
6. Disease-causing bacteria that are resistant to a particular disease
7. When scientists refer to "survival of the fittest," fitness refers to a species'
8. Scientific evidence suggests that the earth's surface has changed significantly over time, as great land masses have moved past and/or into each other. These shifting land masses are connected to subsurface structures called
9. Climate changes and asteroids impacting the earth may be seen as opportunities for evolutionary change.
10. The process whereby one species changes into one or more other species over time is called
11. Fortunately for the world, the golden toad, once thought extinct in its Costa Rican rainforests, has been rediscovered.
12. If you found 20 different plant species in a 1m2 area, but only one of each species, we would say there was
13. The American alligator, once nearly hunted to extinction, is making a comeback. It plays an essential role in its habitat because its nesting mounds and resting holes are important to the lives of other species. The alligator is also important in keeping some prey populations in check. Should such an important species become extinct, there would be devastating consequences to its ecosystem. Such a species is called a/an ________ species.
14. The role that a species plays in its ecosystem, its "way of life" or pattern of living, is called its
15. Some lichens (an "organism" composed of a fungus and an alga) are particularly sensitive to industrial pollutants, especially factory smoke. Scientists have been able to use lichens as a measure of pollution since greater lichen deaths mean higher pollution amounts. Because we can use lichens in this way, we say they are
16. While some landowners may consider beavers a pest, they are important to their ecosystem: the dams they build create wetland that many other species use. Because of the role they play, we call them ________ species.
Brendan Swanson