BIO 373 1st Edition Lecture 16 Outline of Last Lecture I Competition Contd a Regional distribution b Resource portioning c Lotka Voltera Model i Competition graphs ii Outcomes iii coexistance Outline of Current Lecture I Competition contd a Altering the outcome of competition i Disturbance ii Evolution 1 Competition reversal 2 Character displacement II Exploitation a Herbivory Parasitism and Predation b Predators i Methods and diet c Herbivores i Methods and diet d Prey These 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 i adaptations Current Lecture Competition Contd altering the outcome of competition o disturbances fugitive species coexists with another species it competes with dispersal will disperse to vacant patches and colonize when they become available o evolution competition reversal winner becomes loser and loser becomes winner with evolution one species may evolve to be more successful than the other and the other does not evolve character displacement differences between species whose distribution overlaps are great and differences are lost where they do not overlap due to competition for the same limited resource o can competition lead to diversity Yes if two species use the same resource differently Exploitation Organisms need energy and those who consume other organisms participate in exploitation in three ways o Herbivory o Parasitism Lives in host May eat tissue of host or may eat host s nutrients use its resources o Predation Organism kills and eats other organisms Not so clear cut o A herbivore doesn t always eat only plants If conditions do not permit usual diet will possible kill and eat another organisms o A predator may eat plants if its usual prey is unavailable o A plant photosynthesizes and does not typically participate in exploitation but carnivorous plants do Predators o Methods Foraging Sit and wait Ex spiders carnivorous plants o Found where resources are most abundant o Most have a broad diet But do have preferences based on nutrients provided by prey Evident when chooses an organism that isn t abundant Or as abundance increases preference may increase for that resource Herbivores o Eat different parts of plant Usually leaves and seeds most nutrients But will sometimes eat roots Can still kill plant even though technically not a predator because it is unintentional Can affect reproductive success growth and survival of plant o Most have narrow diets insects mostly Some like bigger herbivores i e deer have broader diets Prey o Adapt to avoid being eaten Running away running fast Structural deterrents Ex spines on a sea urchin Toxins Often display bright colors that indicate they re toxic deters predator before even having to toxify Mimicry camouflage Mimic other more dangerous organisms Hide blend with environment Behavior Take cover call out to warn other organisms Masting plants Overwhelm predator with overproduction of seeds Compensation plants Herbivore eating plant is like clipping trimming the plant and allows it to grow and flower more better Appearance plants Camouflage as rocks If mechanically stimulates close up to appear dead