The competitive exclusion of principle states that two species cannot occupy the same niche indefinitely. What is a fundamental assumption of this principle?

4.    In San Francisco Bay, shorebirds compete for small invertebrates living in the mud. Due to natural selection, some birds have very long beaks and legs to reach deep areas and some have short curved beaks. The characters of these birds are so extreme that they are highly specialized in their food sources and there is little overlap in diet. The different body plans of these birds is an example of:   a specialized mutualism. resource partitioning. character displacement. competitive exclusion.

20. In a biological community where diversity is great, such as a tropical rainforest, the abundance of any one species is likely to be A) large in number B) small in number C) widely variable from year to year D) the same from year to year

6. Define ecological niche and describe how it is related to resource partitioning. a. Can two species with identical niches permanently exist in the same community? Why?

Below is an image of three warbler species that all play a similar role in their community and occupy a similar habitat. So instead they occupy different niches. Use these images and the information from lecture to explain what has happened to these species and why this change would be necessary.

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1. Competition (leading to extinction), between flour beetles feeding on wheat flour, could lead to which of the following outcomes (if the sack of wheat flour is cool and wet, with no microhabitat variation)? A. beetles favoring cool, wet conditions will survive, and so will those favoring warm, dry conditions B. beetles favoring warm, dry conditions will survive, while those favoring cool, wet conditions will not C. beetles favoring warm, dry conditions will go extinct, and so will those favoring cool, wet conditions D. beetles favoring cool, wet conditions will survive, while those favoring warm, dry conditions will not E. beetles favoring warm, dry conditions will survive, and so will those favoring cool, wet conditions

1. Bioconversion is the process of turning atmospheric nitrogen into biologically accessible nitrogen. True False

1. With antibiotic resistance rising, researchers are looking for ways to reduce use of these drugs. Some cattle once fed antibiotic-laced food now get probiotic feed that can bolster populations of helpful bacteria in the animal's gut. The idea is that if a large population of beneficial bacteria is in place, then harmful bacteria cannot become established or thrive. Which ecological principle is guid- ing this practice?

5. Which organisms do leopard seals eat? 6. Which organisms eat krill? 7. What producer(s) can be found in the food web? 8. List one important type of organism missing from this food web: 9. If there was a large oil spill which blocked most of the sunlight, decreasing the amount of algae available, how would each of the following populations be affected? 10. Use the food web to identify organisms using the following table so that the killer whale is the quaternary (fourth) consumer. 1. Primary consumer 2. Secondary consumer 3. Tertiary consumer 4. Quaternary consumer Created by counting organisms at each level First level carnivores Herbivores Marine Plankton Population How it Will Be Affected: Cod Leopard seal Killer whale Created by weighing organisms at each level First level carnivores Marine Plankton © 2011 Vanema mn Herbivores Killer whale Created by measuring calories at each level First level carnivores Marine Plankton Herbivores A B с View the three pyramids above. Identify…