Population Ecology: The Texas Mosquito Mystery Population Ecology: The Texas Mosquito Mystery • What are the three types of ecology? 11:52 • Population, Community, Ecosystem • What is population ecology? • Studying how the individuals of a species live together in a certain geographical area • What is a population? • A group of individuals of the same species living and interacting in a certain place • What data do we need to know to truly study population ecology? • Population Density (how many live in a certain area i.e. 5/acre) • Population Dispersion (geographic arrangement i.e. evenly spaced, all found in a certain tree, etc) Population Ecology: The Texas Mosquito Mystery Population Ecology: The Texas Mosquito Mystery • What factors drive population growth? 11:52 • Fecundity (# offspring in a lifetime) • Limiting Factors • Density Dependent – inhibit growth of a population because of environmental stress based on a population size • i.e. food, water, shelter, predator/prey, disease • Density Independent – factors that are not based on the size of the population • i.e. climate change, storms, earthquakes, hurricane • What is carrying capacity? • Number of individuals a habitat can sustain with the resources it has available Population Ecology: The Texas Mosquito Mystery Population Ecology: The Texas Mosquito Mystery • What are the two types of population growth? 11:52 • Exponential – provides a J-shaped curve and occurs when the individuals reproduce at a constant rate because the environment can support a larger population • Logistic – S-shape curve and occurs as resources become less available, the carrying capacity is reached, and the reproductive rate slows down or stops • What is the formula for population growth? Human Population Growth Human Population Growth • What is the R vs K Selection Theory 10:53 • Theory that addresses how different species increase their populations • R species reproduce very quickly • Reproduce often, Lots of offspring, Very little parental support • K species reproduce more slowly • Reproduce less often, Few offspring, Lots of parental support • How have humans been able to grow at R-levels despite being K-species? • Increasing their carrying capacity by overcoming limiting factors • How have we overcome our limiting factors to increase our carrying capacity? • Better agriculture • Better medicine • Environmental and Technological advances (i.e. sanitation, living in inhospitable areas) Human Population Growth Human Population Growth • What is the human carrying capacity? 10:53 • Nobody knows but estimated to be between 10 and 15 billion • What is an ecological footprint? • A calculation based on how much land and how many resources each person needs to survive • When did the rate of human population growth peak? • 1962 • What factors have contributed to the decrease in the RATE of human population growth? • Culture of Women – Fewer offspring, more education, more working • Lifestyle – urban vs farm living.