4.2 Human Population Human Population Growth Chapter 4 Population Ecology 4.2 Human Population Human Population Growth The study of human population size, density, distribution, movement, and birth and death rates is demography. 1

Technological Advances Chapter 4 Population Ecology 4.2 Human Population Technological Advances For thousands of years, environmental conditions kept the size of the human population at a relatively constant number below the environment’s carrying capacity. Humans have learned to alter the environment in ways that appear to have changed its carrying capacity. 2

Human Population Growth Rate Chapter 4 Population Ecology 4.2 Human Population Human Population Growth Rate Although the human population is still growing, the rate of its growth has slowed. 3

Trends in Human Population Growth Chapter 4 Population Ecology 4.2 Human Population Trends in Human Population Growth Population trends can be altered by events such as disease and war. Human population growth is not the same in all countries. 4

Zero Population Growth Chapter 4 Population Ecology 4.2 Human Population Zero Population Growth Zero population growth (ZPG) occurs when the birthrate equals the death rate. The age structure eventually should be more balanced with numbers at pre-reproductive, reproductive, and post-reproductive ages being approximately equal. 5

pre-reproductive stage, reproductive stage, and post- Chapter 4 Population Ecology 4.2 Human Population Age Structure A population’s age structure is the number of males and females in each of three age groups: pre-reproductive stage, reproductive stage, and post- reproductive stage. 6

Invasive Species An invasive species is defined as a species that is: 1) non-native (or alien) to the ecosystem under consideration and 2) whose introduction causes or is likely to cause economic or environmental harm or harm to human health. Invasive species can be plants, animals, and other organisms (e.g., microbes). Human actions are the primary means of invasive species introductions.

Emerald Ash Borer (EAB) INVASIVE SPECIES-not native to Michigan Came to Metro Detroit in packaging crates from China Only eats ASH trees in USA Ash trees-used for firewood, furniture, baseball bats, packing material etc… Arrived around 1992-population rapidly increased (no natural predator) and by 2002 it was a noticeable problem woodpeckers (we don’t have many left) are starting to prey on them Has already killed 15 million Ash trees

Has spread to other states-Ohio, Indiana, Illinois, Maryland, and even Canada Follow Insect Life Cycle = Metamorphosis Adult, Egg, Larva, Pupa 1-2 years for adults to emerge Larva bores into tree and eats the inside-killing the tree in 1-2 years AS OF NOW THE ONLY SOLUTION IS TO LIMIT THE FOOD SOURCE-REMOVE ASH TREES and BURN ALL INFECTED WOOD DNR-working on traps (they seem to like purple) POTENTIALLY-$1 + BILLION PROBLEM

Asian Carp Two species – Bighead and Silver Imported by catfish farmers in the 70’s to remove algae from ponds During massive floods in the 90’s, catfish farmer’s ponds overflowed and released the carp into the waterways. Now they are the most abundant species in some parts of the Mississippi River.

Asian Carp and the Great Lakes Asian carp eat a tremendous amount of food, taking away from other species of fish. They can weigh up to 100 lbs. They are very capable of surviving in the Great Lakes due to the fact that the lakes resemble their habitat in Asia. Researchers predict the demise of the Great Lakes Ecosystem if these fish are allowed to thrive.

Population Quiz! Covers chapter 4 (Sections 1 and 2) Focuses mostly on the graphs they show Exponential and Logistic Growth Human Population, Age Structure, etc. Study bookwork from Section 4.1 and 4.2 / Read over sections Quiz is about 10 questions long and is fill in the blank PowerPoints will be online by tonight