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Crash Course Ecology
Hank Green teaches you ecology!
Learn, study and understand how organisms relate to one another and to their surroundings. Start with the history of life on earth, then cover topics ranging from population ecology, community ecology, ecosystem ecology, to conservation and restoration ecology.
Hank discusses the history of life on Earth (including major events such as oxygenation of the atmosphere and mass extinctions).
Hank discusses population ecology, including the factors that limit population growth, using the example of a mosquito population.
Hank explores human population growth, exponential growth of populations, and R- and K-strategists.
Hank explores community ecology, the competitive exclusion principle, and how different species can coexist by occupying different niches.
Hank explores adaptations of predators, the evolutionary arms race between predators and prey, and various types of predation (including herbivory and parasitism).
Hank examines how ecological communities change after a disturbance.
Hank discusses ecosystems, trophic structure, and the flow of energy through food webs.
Hank explains how carbon and water are recycled through ecosystems and the biosphere.
Hank discusses how nitrogen and phosphorous are recycled through ecosystems and the biosphere.
Hank presents examples of how human activity can affect ecosystems.
Hank discusses different forms of pollution and their ecological effects.
Hank discusses different types of biodiversity, as well as how biodiversity can be measured, preserved, and restored.