Visualizing Environmental Science

Human population

increase

Land-use

change

(habitat loss))

Climate

change

Pollution

Overexploitation

(for example,

overfishing)

Invasive

species

Increasing
economic
activity

Increased

use of

technology

Declining

biological

diversity

Social, political, and

cultural factors

350

300

250

200

150

Number of elephants^100

50

0

1965–69

Period

1975–79 1985–89 1995–99 2005–09

Population A

Population B

Population C

Population D

Frans Lanting/Mint Images/ Getty Images

Philippe Bouché, Iain Douglas-Hamilton, George Wittemyer, Aimé J. Nianogo, Jean-Louis Doucet, Philippe Lejeune, Cédric

Vermeulen. “Will elephants soon disappear from West African Savannahs?” PLOS One, June 22, 2011.

Scott S. Warren/NG Image Collection

a. Causes of Declining Biological Diversity.

In this highly simplified diagram, indirect causes (tan) interact

with and amplify the effects of one another and of direct causes

(gray). All of these factors interact in complex ways.

b. Destruction of the World’s Wildlife Habitats.

This tiny island, located in the Panama Canal, was once a

hilltop in a forest that was flooded when the Panama Canal was

constructed.

c. Isolating Wildlife Habitats.

Roads and agricultural lands effectively

isolate the scattered remnants, or

“islands,” of forest. Photographed in

Paraná State, Brazil.

d. Evidence of Land-Use Conflicts.

Four West African elephant populations declined in a region

where they compete for space with humans, 1965–2009.

Global

Locator

BRAZIL

NG Map

s

PANAMA CANAL

Environmental InSight ✓✓THE PLANNER

Threats to biodiversity

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Interpreting Data

How might increased use of technology

contribute to declining biological

diversity?

Endangered and Extinct Species 383