Personal definition of ecology: The study of an ecosystem and the inhabitants of it, including biotic and abiotic factors and their interactions

Ecology: Study of relationships between organisms and the environment, though this definition lacks full coverage of the subject due to it’s age. The definition was created when people explored further areas and needed a way to categorize them, from people like Charles Darwin. Covers many scales, from microbes to global processes. Includes abiotic and biotic worlds, and how they effect things like climate, time, space, and future generations

Field of ecology: Started with “this thing does this” and over time became interconnected. This is a scientific discipline that informs political decisions about resource use, pollution, climate change, and other issues. Many different approaches

Disciplines include abiotic interactions, microbes, organisms, populations, communities, biomes, and Earth. All of these interact with one another

Evolution: The process by which different kinds of living organisms are thought to have developed and diversified. This is the framework for ecological studies

Natural Selection: Organisms adapt to their environment to survive, survived genes are passed on to the next generation

Wolves have impacted Yellowstone National Park’s ecology. By originally killing off all the wolves, there were changes to other animal population sizes and movements, and differences with the plants, so they reintroduced wolves to the area which restored the original environment. Natural plants were restored, because their consumers started being predated by the wolves whereas before they had no predator and overgrazed. Specifically, this happened with Elk and Aspen trees. In 2001, Ripple et. al. 2001 tracked the elks through pellets, and found an inverse relationship between the amount of elk and the amount of wolves, being tracked by satellite. As for the trees, where the wolves were there were more trees. All of this was in lowland wet areas. Trees were shorter without wolves, but with wolves they had more time to grow higher. Kaufmann et al. 2010 studied this again, but put fences in the area to directly observe and keep out elk. One weird finding through is that where the elk are at risk of being eaten, they will eat a lot of aspen trees. Overall, there is no protection for the trees from the wolves, according to the new data. This ended up being because elk went where plants were, and wolves went where the elk were, and the elk would just constantly move. They couldn’t find the pellets, as the elk weren’t in their typical areas. After the revisitation, Beschta and Ripple et al. 2016 shows that things leveled out to where they would be expected to be. Trees did better with the wolves present, which is good for beavers in the area.

Trophic cascade: Removal of top predators results in reciprocal changes in the relative populations of predator and prey through the food chain. Things change without the top species. This is characterized by a drastic change to an ecosystem.