#AP Environmental Science: Demographic Transition Model - Your Ultimate Guide

Hey there, future AP Environmental Science rockstar! Let's break down the Demographic Transition Model (DTM) – a key concept that can unlock some serious points on your exam. Think of this as your late-night, pre-exam pep talk, designed to make everything click. Let's get started!

#Understanding the Demographic Transition Model

The Demographic Transition Model (DTM) is a visual representation of how a country's population changes over time as it develops. It's like a story, with different chapters, each showing a different stage of population growth. Understanding this model is crucial because it connects to so many other topics, from resource use to urbanization.

#The Stages of the DTM

Let's walk through each stage, step by step:

Memory Aid

Remember the stages with this simple phrase: "High, High, Low, Low, Huh?" This refers to the birth and death rates in each stage.

#Stage 1: High Stationary

Characteristics: High Crude Birth Rate (CBR) and High Crude Death Rate (CDR), resulting in a low growth rate.
Why? High birth rates are due to lack of family planning, high infant mortality rates, and the need for labor on farms. High death rates are due to disease, poor sanitation, and limited access to healthcare.
Example: Historically, pre-industrial societies. No countries are currently in Stage 1. #### Stage 2: Early Expanding
Characteristics: High CBR, but CDR begins to decrease, leading to a high growth rate.
Why? Improved healthcare, sanitation, and food availability lead to lower death rates. Birth rates remain high due to cultural norms and a lack of access to contraception.
Example: Many developing countries experiencing rapid population growth.

#Stage 3: Late Expanding

Characteristics: CBR starts to decrease, CDR continues to decrease, and the growth rate slows down.
Why? Increased access to education, family planning, and urbanization lead to lower birth rates. Death rates continue to fall due to advancements in medicine and public health.
Example: Countries that are industrializing and becoming more urbanized.

#Stage 4: Low Stationary

Characteristics: Low CBR and low CDR, re...

Demographic Transition