A species of flowering plant lives in open meadows in temperate regions of North America. Each plant produces either blue, purple, or red flowers.
Several different pollinators visit the flowers, and the plant is preyed upon by
several insect species and herbivores. Butterflies prefer red and purple
flowers and bees prefer blue flowers. The population numbers for this
species have remained constant over the time period shown in the graph.
Data collected over several years for one population of this species are
shown in the graph below. Which of the following scenarios is the most likely
explanation of the data?
Blue
Purple
Red
0.
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1. seamount a raised footwall block between normal fault creates this 2. syncline break between rocks where a hanging wall rises relative to a footwall 3. hot spring on rolling hills, this a dip between hills 4. volcanic neck created when a block with hanging walls slips down between normal faults 5. caldera underwater volcano that never reaches above sea level 6. horst natural hot water on earth's surface containing many minerals 7. graben underwater volcano whose top is eroded flat by waves 8. crater less than a mile in diameter; looks like a bowl at the top of a volcano 9. guyot magma that filled the central vent that remains after the volcano has eroded 10. reverse fault over 1 mile in diameter; looks like a bowl over a volcano