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# EcoEco#3(ch.14Notes)

Question | Answer |
---|---|

What does it mean when we say a species is "introduced", "exotic", or "non-native"? | When a species has been introduced to a region of the world where it has not historically existed. |

If a species spreads rapidly and negatively affects other species, what is the species called? | Invasive. |

Do parasitoids kill their prey? | Yes, eventually. |

What is an example of parasitoids keeping a population in check? | Parasitoid wasps on populations of red scale insects. |

What are the two kinds of predators? | Mesopredators and top predators. |

What has been the cause that has allowed 60% of all mesopredators to expand their geographic ranges in North America? | Reducing/eliminating top predators to protect human livelihood. |

Why was it a problem in Australia to remove the dingoes and feral dogs to reduce killing sheep? | The dingoes and feral dogs also preyed on red foxes who also happen to kill sheep. The decrease in dingoes and dogs led to an increase in red foxes which resulted in triple the loss of sheep. |

Name three examples of herbivores keeping plants in check. | 1)the prickly pear cactus moth in Australia (positive effect) 2)beetle herbivory on Klamath weed (positive effect) 3)deer in Gwaii Haanas National Park Reserve (negative effect) |

Define biomass. | The total mass of organisms in a given area or volume. |

True or false. Studies demonstrate that the influence of herbivores on the abundance of producers affects the species composition of the entire community. | True. |

Name an example of the close synchrony of population cycles between a consumer and the population they consume, suggesting that the oscillations are the result of interactions between them. | Cyclic fluctuations in the populations of snowshoe hares and lynx. |

What was the take away from Huffaker's predator-prey lab experiment? | Stable population cycles can be achieved when the environment is complex enough that predators cannot easily find scarce prey. |

How does the Lotka-Volterra model incorporate oscillations in the abundances of predator and prey populations and shows predator numbers lagging behind those of their prey? | This model does this by calculating both the rate of change in the prey population and the rate of change int he predator population. |

What does the N mean in the Lotka-Volterra prey population equation? | The number of prey. |

What does the P mean in the Lotka-Volterra prey population equation? | The number of predators. |

What does rN mean in the Lotka-Volterra prey population equation? | The exponential growth of a prey population based on the intrinsic growth rate. |

What does r mean in the Lotka-Volterra prey population equation? | The intrinsic growth rate. |

What does cNP mean in the Lotka-Volterra prey population equation? | The loss of individuals due to predation. |

What does the c in cNP mean in the Lotka-Volterra prey population equation? | The probability of an encounter leading to the prey's capture. |

What does the NP in cNP mean in the Lotka-Volterra prey population equation? | The probability of a random encounter between predators and prey. |

What does acNP mean in the Lotka-Volterra predator population equation? | The birth rate of the predator population. |

What does cNP mean in the Lotka-Volterra predator population equation? | The number of prey consumed by the predator population. |

What does "a" mean in the Lotka-Volterra predator population equation? | The efficiency of converting consumed prey into predator offspring. |

What does mP mean in the Lotka-Volterra predator population equation? | The death rate of the predator population. |

What does "m" mean in the Lotka-Volterra predator population equation? | The per capita mortality rate of predators. |

What does P mean in the Lotka-Volterra predator population equation? | The number of predators. |

How do we know when a population is stable based on the Lotka-Volterra equation? | 1)exponential growth of prey based on intrinsic growth rate minus the loss of individuals due to predation equals zero 2)consumption of prey equals the addition of prey 3)#predators equals the ratio of prey's growth rate & predator's capture efficiency |