Biol 301 1nd Edition Lecture 15 Outline of Last Lecture I. PredationII. DefensesIII. CoevolutionIV. ParasitesOutline of Current Lecture II. CompetitionIII. ResourcesIV. ConditionsCurrent LectureCompetition- Intraspecific competition: competition among individuals of the same species. Negative density dependence is a common type of intraspecific competition, where an increase in a population’s density causes a decline in the growth rate of the population.- Interspecific competition: competition among individuals of different species. Interspecific competition can cause the population of one species to decline and eventually die out.- Darwin suggested that competition is most intense between related species because they have similar traits and consume similar resources.- For related species that compete strongly, natural selection should favor differences in habitat use.- Competition can also be intense among distantly related species that consume a common resource.Resources• Resource: anything an organism consumes or uses that causes an increase in population growth rate when it becomes more available. Ecological factors that cannot be consumed (e.g., temperature) are not considered resources. Resources for plants can include sunlight, water, and soil nutrients. Resources for animals can include food, water, and space. Any substance or factor that is both consumed by an organism and supports increased population growth rates as its availability increasesThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.o Consumed, availability decreaseso Used for maintenance and growtho Reduced availability reduces population growth- Renewable resources: resources that are constantly regenerated (e.g., seeds, sunlight).- Nonrenewable resources: resources that are not regenerated (e.g., space).- Renewable resources can originate from inside or outside the ecosystem in which competitors live (e.g., dead leaves fall into streams from the surrounding forest). - Resources from outside the system do not respond to the rate of resource consumption.- In contrast, competitors can affect the supply of resources and demand for resources that originate within the ecosystem.- Competitive exclusion principle: two species cannot coexist indefinitely when they are both limited by the same resource.- When two species are limited by the same resource, one species is often a better competitor survives better when resources are scarce.Conditions/Disturbances/Predation- Abiotic Conditions- The ability to compete well may be overwhelmed by the ability to persistin harsh abiotic conditions.- Asymmetric Competition - A competitive relationship between two species in which each has a competitive advantage with respect to different limiting factors in the environment- Competitive interactions can also be altered by disturbances.- There are often trade-offs between competitive ability and resistance to predators or herbivores; the most competitive organisms are often the most susceptible to predation or herbivory.- Predators can reverse the outcome of competition.- Herbivores can also alter the outcome of competition.- Exploitative competition: competition in which individuals consume and drive down the abundance of a resource to a point that other individuals cannot persist.- Exploitative competition is considered indirect competition because it occurs through a shared resource.- Interference competition: when competitors do not immediately consume resources but defend them; considered direct competition.- Apparent competition: when two species have a negative effect on each other through an enemy—including a predator, parasite, or herbiviore.- Aggressive interactions are an effective form of interference competition.- Allelopathy: a type of interference competition that occurs when organisms use chemicals to harm their competitors.- Allelopathy can be an effective strategy for invasive plants.- Two species can share a resource and have negative effects on each other through an enemy, such as a predator, parasite, or herbivore.- Apparent competition could be generated if one species facilitates the enemy of another