Population Growth And Habitat Destruction
Biodiversity is affected by human population size and resource use.
1 person is born every 8 seconds1 person dies every 12 secondsThat is a net gain of one person every 13 seconds.
Understanding population growth • In order for growth to continue forever, we would need an infinite amount of space, energy, and resources. • So what happens to steady growth in a limited space? • EXPONENTIAL GROWTH
Exponential Growth • DEFINITION:The number of organisms will increase exponentially until nutrients run out. • Typically the first organism splits into two, which then split into four, and then doubles to 8, etc. • Usually doubles or triples, but the human population increases by 1.5x each year.
So what? • In that example, the bacteria was only limited by the space of the bottle. • What about human population, that is limited by the amount of oxygen, food, energy, space, nutrients, disease, etc? • Because of these limiting factors, populations reach their carrying capacity and do not over-run the world.
Greatest threats to biodiversity • Habitat destruction • Invasive species • Population growth (humans) • Pollution • Over harvesting HINT: Think of the acronym “HIPPO” to remember these five points