Chapter 1 Flashcards
How might understanding one level of ecological organization help us understand processes occurring at a higher level of ecological organization?
Understanding one level or organization can help us understand how it might affect the others. In the case of a drought, scientists might want to understand how an ecosystem will respond. Additionally scientists might want to see how plants and animals respond to the lack of water and how individual responses affect plant and animal population. Moreover scientists might ask how a change in the populations might affect species interactions and how that might affect flow of energy and matter in an ecosystem
At the population level, what would happen to a population of animals that was not in a dynamic steady state over long periods of time?
The population would go extinct. Lack of food resources, increases competitors, and lack of protection from predators and shelter may lead the population to go extinct
Why are phenotypes the product of both their genes and their environments?
Environmental factors such as diet, temperature, oxygen levels, humidity, light cycles, and the presence of mutagens can all impact which of an animal’s genes are expressed, which ultimately affects the animal’s phenotype. evolution by natural selection is another reason because individual organisms can vary in their traits and the variation of traits causes individuals with a certain phenotype to experience higher fitness. The traits from the parents are also passed onto the offspring.
How does the law of conservation of matter relate to understanding ecology?
Law of conservation of matter says that Matter can change form through physical and chemical changes, but through any of these changes matter is conserved. The same amount of matter exists before and after the change—none is created or destroyed. This is related to ecology because they can track matter through an ecosystem and see how much resources are needed per individual. Biology calls this cycling of matter as nutrient cycling. Another common example would be: grass —> eaten by herbivores—> matter in grass used to create herbivore body —> herbivore body eaten by carnivore —>
If natural selection favors adaptive phenotypes, in what ways might prey populations evolve if they experience predation over many generations?
If selection favors adaptive phenotypes then prey species can evolve by adapting traits of previous members of the species who survived and whos traits were favored by selection. milkweed plants have evolved the ability to produce a sap that is toxic to most herbivores. Caterpillars evolved to be able to eat them, but limiting most herbivores from consumption will increase the chances of survival of milkweed.
In the experiment on herbivore insects consuming the leaves of oak trees (Section 1.4), describe how the researchers could have also conducted a natural experiment in addition to their manipulative experiment.
Manipulative hypothesis: A process by which a hypothesis is tested by altering a factor that is hypothesized to be an underlying cause of the phenomenon. (scientists caging birds to see if lack of birds increases insects). Natural experiment they can just observe as is no birds in cages
How might parasites have similar effects as herbivores that only consume a few leaves on a plant.
Parasites might have a similar effect as herbivores that only consume a few leaves on a plant in that parasites only consume a small part of the host. Rarely kill just harm. Same with herbivores on plants.
When experimental manipulations are conducted to test a hypothesis, what is the purpose of including a control?
A control is a manipulation that includes all aspects of an experiment except the factor of interest. In the oak tree experiment, the caged trees served as the treatment, whereas the uncaged trees served as the control. The manipulation, also known as the treatment, is the factor that we want to vary in an experiment and often times one of the manipulations is the control.
