What is a Region?

"a scientific device that allows us to make spatial generalizations based on artificial criteria that we establish for the purpose of constructing regions"


"an area on the earth's surface marked by certain properties"

The definition that I like best is "an area on the earth's surface marked by certain properties". For example our textbook divides South America into four regions. We could spend all semester just studying South America and its 15 countries. By studying these four regions, each with its own common properties, we are able to learn much about the continent and have time to study the rest of the world.

It must be noted that the properties studied are selected by the person defining the region. Therefore regions are quite arbitrary, yet scientific. I may arbitrarily select the properties of "students who have blue eyes". I then scientifically gather data to find where blue-eyed students live. I could then select categories like: less than 10%, 10% to 25%, and over 25%. I could plot these regions showing the density of blue-eyed students on a map.


What is a Realm?

Our textbook defines as geographic realm as "the basic spatial unit in our world regionalization scheme. Each realm is defined in terms of a synthesis of its total human geography -- a composite of its leading cultural,, economic, historical, political, and appropriate environmental features."

A simple definition of a realm would be the largest logical regions into which we can divide the whole world. The authors of our textbook divides the world into 12 geographic realms. Each chapter of the textbook discusses one realm.

Note that realms can be defined differently by different geographers and that realms can change. The authors of your textbook once divided the realm of East Asia into two different realms: the Chinese Realm and the Pacific Rim composed of Japan, South Korea, Taiwan, and Singapore. Now they think that it is more appropriate to combine them into one realm. Also, in the realm of North Africa and Southwest Asia (chapter 6) our authors include five countries that used to be part of the former Soviet Union (a region that he calls Turkestan). Most other textbook authors include these five countries in a realm called "the former Soviet Union". So in which realm SHOULD they be? It doesn't really matter. It depends on the criteria that the author wishes to emphasize. This is the arbitrariness involved in forming regions. Our authors emphasize cultural and physical criteria, whereas other authors may stress historical and economic criteria.


Transition Zones

ALL regional boundaries are transition zones. Some are large, like the boundary between Sub-Saharan Africa and North Africa. Others may be quite narrow and distinct, but they are still transition zones. For example the boundary between North American realm and Middle American realm runs along the US / Mexico border [wwrealm]. Even though this seems rather distinct, there are similar characteristics on both sides of this border (like Spanish language spoken in Texas and southern California, the Catholic Religion, and similar physical environment). This realm boundary, like all regional boundaries, is a transition zone.


Why do geographers use regions?

Geographers study a very wide range of issues (utilizing the spatial perspective). Regions are one way to organize and simplify this vast amount of information. Even though regions are "made-up" by the geographer, they are designed in such a way that the information they provide will be useful. I'm not sure if a map of the density of blue-eyed students would be useful, but maps of climatic regions [climate], or world income levels [wbgnpmap] can help us to understand the world around us.

Biologists do the same thing when they divide living organisms into different groups with similar characteristics to better understand the great variety of living organisms.


Regional Criteria

What criteria could be used to designate a REGION? As we have seen - virtually anything. In this world regional geography course we will use our four class themes of:

ALSO, regional boundaries tend to pass though areas of sparse population. Therefore we may add POPULATION CLUSTERS as a fifth criterion

For each world realm we will "apply" these criteria. This means we will learn the physical, cultural, economic, and historical characteristics that "define" the realm, or that make it different from other realms. We will also examine the boundaries of the each realm looking for physical barriers like mountains, deserts, swamps, etc. that separate the realms, and looking for differences in the other regional criteria. This involves more than memorization. You should be able to examine maps and data to describe and explain why the authors divided the world into the realms that they did.


Application of the Regional Criteria

Use the regional criteria to explain why geographers divide Africa into NORTH AFRICA and SUB-SAHARAN AFRICA.

My wife teaches first grade and when her class studies Africa they study the whole continent, from Morocco and Egypt in the north to South Africa in the south [afntos]. But most college world regional geography textbooks divide the continent of Africa into two different chapters or realms [SSA] with (1) North African and Southwest Asia in the north and (2) Sub-Saharan Africa in the south.


Because it makes sense - geographically - to divide Africa in this manner. This can be seen if we apply the regional criteria to the continent of Africa. We will do this by looking at maps of Africa to see if the north is really significantly different from the south and if there exists a physical barrier between the realms. We will use Africa as our example in this introductory exercise, BUT THROUGHOUT THIS COURSE YOU SHOULD LEARN TO APPLY THE REGIONAL CRITERIA TO ALL OF THE WORLD'S REALMS.

Look at the following maps and compare them with this map of Africa [SSA]. Which criteria best explain why geographers often divide Africa into two different realms? (Note: not all of the criteria will explain all realm boundaries.)

Physical: Climate
Physical: Sahara
Cultural: religion
Cultural: language
Cultural: race1, race2
Cultural: political
Historical: pre-colonial
Historical: colonial
Historical: culture hearths
Population Clusters

Realm boundaries often pass through areas of low population density. Is this true for the border between North Africa and Sub-Saharan Africa? [Population Clusters]

So why is Africa divided into two realms?

Now click on the link above to get a summary of how the regional criteria can be used to divide Africa then go back through the maps to "see" the basis for this summary. [click here for list of maps]