Evolution And History

54 CHAPTER 3 | Living Primates

The diversity of life on earth attests to the fact that living
organisms solve the challenge of survival in many ways.
In evolutionary terms, survival means reproducing subse-
quent generations of the species and avoiding extinction.
Over the course of countless generations, each species has
followed its own unique journey, an evolutionary history
including random turns as well as patterned adaptation
to the environment. Because new species are formed as
populations diverge, closely related species resemble one
another due to recent common ancestry. In other words,
closely related species have shared part of their evolution-
ary journey together. With each step living creatures can
only build on what already exists, making today’s diversity
a product of tinkering with ancestral body plans, behav-
iors, and physiology.
In this chapter we will look at the diversity of living
primates, the group of animals to which humans belong.
By doing so, we will gain a firmer understanding of those
characteristics we share with other primates, as well as
those that distinguish us from them and make us distinc-
tively human. Figure 3.1 shows the natural global distribu-
tion of living and fossil primates. It also indicates where

the twenty-five most endangered primate species are

struggling to survive. Among them is the Tonkin snub-

nosed monkey in northern Vietnam, with only 150 indi-

viduals remaining in the wild.

Methods and Ethics

in Primatology

Just as anthropologists employ diverse methods to study

humans, primatologists today use a variety of methods

to study the biology, behavior, and evolutionary history

of our primate cousins. Some primatologists concentrate

on the comparative anatomy of ancient skeletons, while

others trace evolutionary relationships by studying the

comparative physiology and genetics of living species.

Primatologists study the biology and behavior of living

primates both in their natural habitats and in captivity in

zoos, primate research colonies, and learning laboratories.

The classic image of a primatologist is someone like

Jane Goodall, a world-renowned British researcher who

Western Hoolock

gibbon (India,

Bangladesh,

Myanmar [Burma])

Golden-headed

langur (Vietnam)

Cross River gorilla (Nigeria/Cameroon)

Pennant’s red colobus (Equatorial Guinea)

Miss Waldron’s

red colobus

Roloway guenon

Variegated

spider monkey

Brown-headed

spider monkey

Yellow-tailed

woolly monkey

Pig-tailed langur

(Indonesia)

Sumatran orangutan

(Indonesia)

Sahamalaza Sportive lemur

Greater bamboo lemur

White-collared lemur

Tara River

red colobus

Kipunji

Rondo dwarf galago

Silky sifaka

Haiman black-crested

gibbon (China)

Gray-shanked Duoc

langur (Vietnam)

Tonkin snub-nosed

monkey

Delacour langur

Siau Island

tarsier (Indonesia)

Living Fossil only

Figure 3.1 The global distribution of living and fossil nonhuman primates, showing the global
distribution of living and fossil nonhuman primates. In the past, when more of the world was
covered by tropical forests, the range of primates was far greater than it is now. Today, human
activity threatens our primate cousins throughout the globe. The figure also shows the location of
the twenty-five most endangered primate species today.