POPULATIONS I-IV
What term describes the phenomenon where the rate of change in population size increases over time due to compounding, resulting in a j-shaped curve on a linear scale where the rate of increase is constant?
What is exponential growth?
What term describes the type of competition where organisms directly interfere with each other's access to resources, often involving antagonistic interactions such as physical fighting?
What is direct interference competition?
What are the two main effects predators can have on prey populations, and how do they differ in their impact?
What are consumptive effects (reducing prey abundance) and non-consumptive effects (shaping prey behavior)?
What mathematical parameters are crucial for understanding disease transmission in population models, and how do they influence the spread of infectious diseases?
What are the transmission coefficient (β), recovery rate (γ), and mortality rate (m)? Higher transmission coefficient and lower recovery/mortality rates contribute to faster disease spread.
What term refers to the population size where birth rates equal death rates, leading to a stable population size?
What is carrying capacity K?
What term refers to the portion of the fundamental niche that a species actually occupies in the presence of competitors?
What is the realized niche?
In the classic Paramecium and Didinium experiment, what environmental manipulation led to coexistence of both species?
What is providing hiding places for Paramecium, which reduced predation pressure from Didinium?
What is the mathematical concept behind herd immunity, and why is it important for vaccination programs?
What is the susceptibility threshold (ST), where vaccination reduces the susceptible population below the threshold required for disease spread, thus protecting the entire population?
What are the four mechanisms of density dependence that regulate population growth?
What are food or nutrient depletion, space depletion, social interactions, and waste product accumulation?
How does competition typically affect the abundance of coexisting competitors compared to their abundance in the absence of competition?
What is coexisting competitors are typically at lower abundance compared to their abundance in the absence of competition?
What are the possible strategies plants can evolve in response to herbivory, and how do they differ from those of prey in predator-prey interactions?
What are tolerance, resistance, and avoidance? Unlike prey, plants cannot flee or fight back against herbivores.
Define zoonotic diseases and explain why ecologists were not surprised by the COVID-19 pandemic.
What are diseases that can spread between humans and animals? Ecologists were not surprised because emerging infectious diseases (EIDs), especially zoonoses originating from wildlife, are predicted by factors like human density, growth rate, and interactions with wildlife.
What type of population growth is indicated by an age structure diagram where there are many individuals in the younger age classes and fewer in the older age classes?
What is increasing population growth?
What evolutionary phenomenon, driven by competition, describes the reduction of niche overlap between competing species over time through trait evolution?
What is character displacement?
How do bison contribute to the prolongation of the growing season for plants, according to the Green Wave Hypothesis?
What is by heavily grazing on plants, bison stimulate the growth of fresh, nutritious shoots, extending the season of high-quality forage?
Differentiate between microparasites and macroparasites, and provide examples of each.
What are microparasites, which are typically small and live inside cells (e.g., viruses, bacteria), and macroparasites, which live on or inside the body but not within cells (e.g., worms, ticks)?
What stage of the demographic transition model is characterized by falling death rates due to improved sanitation and healthcare, while birth rates remain high?
What is stage 2?
In an experiment testing competition between seaweeds and corals, what was the evidence for both direct interference and exploitation (indirect) competition mechanisms?
What is the seaweeds caused harm to corals when grown together (evidence for competition), and seaweed chemical extracts alone also caused harm to corals (evidence for direct interference)?
In the mites on oranges experiment, what was the result when habitat complexity was increased to allow prey to disperse faster than predators?
What is prey populations persisted longer on isolated oranges, indicating that increased habitat complexity favored prey survival?
Describe a complex life cycle of a parasite and explain how it benefits from manipulating the behavior of its intermediate host.
What is an example of a parasite that uses a snail as an intermediate host, altering its behavior to increase the chances of predation by birds, facilitating the completion of its life cycle?