Second Nature: Economic Origins of Human Evolution

Published by EH.NET (May 2002)

Haim Ofek, Second Nature: Economic Origins of Human Evolution.

Cambridge: Cambridge University Press, 2001. x + 254 pp. $27.95 (paperback),

ISBN: 0-521-62534-3; $74.95 (hardback), ISBN: 0-521-62399-5.

Reviewed for EH.NET by Jo?o Ricardo Faria, School of Social Sciences,

University of Texas at Dallas.

Remarkable books build their reputations by providing comprehensive and

exhaustive answers to well established problems, or by setting a new agenda of

research through the provision of new data and by looking at old problems with

a new and fresh approach. This highly readable book of Haim Ofek falls into

both categories. The book applies economic principles to understand many

important issues in human evolution. However Ofek does not confine his analysis

to economics. On the contrary, his assessment of the economic origins of human

evolution relies heavily on literature, data and facts from anthropology,

biology and other natural sciences.

In the introduction, Ofek exposes the issues and puzzles about human evolution

that possess an important economic dimension — such as the domestication of

fire, the creation of stone tools, human migration from Asia to America in the

midst of an ice age, the transition from the feed-as-you-go strategy through

hunting-gathering and finally to agriculture, and the paradox of husbandry. The

book addresses these issues in different ways: using available evidence, making

logical inferences, and proposing new conjectures. Underlying the answers lies

the main thesis of the book, that human propensity to exchange played a central

role in human evolution.

The remainder of the book is divided in two parts: bioeconomics and

paleoeconomics. Both parts are divided in six chapters. Chapter two deals with

exchange in human and nonhuman societies. Ofek identifies two patterns of

exchange, the nepotistic and the mercantile. Nepotistic exchange is regulated

by evolutionary mechanisms such as kin selection and sexual selection, while

mercantile exchange is purely human. Chapter three discusses the evolutionary

origin of humans’ predisposition to exchange. The key question is: Was exchange

an agent of human evolution or merely a late by-product of human intelligence?

The problem arises because the expansion of the human brain seems to be

excessive relative to prehistoric needs for human survival. However, according

to Darwin’s principle of utility, natural selection cannot produce a structure

that is harmful to an organism, nor a structure of greater perfection than

necessary for an organism at a given stage in its evolutionary story. Alfred

Russel Wallace (who shares with Darwin the creation of the concept of natural

selection) concluded that forces other than natural selection were at action to

explain the evolution of the human brain. For Ofek, exchange is the independent

agent of brain evolution.

Chapter four considers the evolutionary implications of the division of labor

to address the fundamental problem of human diversity in skills and talents.

While the division of labor may happen in nonhuman societies, it never occurs

in any significant way above the level of the organism or its immediate kinship

group. Ofek attributes to mercantile exchange the capacity to enable the

division of labor in human society to operate on a large scale within and

across populations.

Chapter five makes an interesting link between the transitions from the

feed-as-you-go model of subsistence to hunting-gathering to the peculiarities

of human gut, which is markedly small relative to body size. In the

feed-as-you-go strategy, food items are ingested on the spot and strictly in

the order of acquisition. However, by following this strategy the feeder faces

a trade-off between procurement and digestion. If it decides to minimize the

energy cost in procurement, it will face the cost of digestion. On the other

hand, if the feeder decides to minimize the costs of digestion, it runs the

risk of starvation because of the costs of procurement. The hunting-gathering

strategy solves this dilemma because it separates in space and in time the act

of procurement from the act of ingestion and thereby, it minimizes both costs.

As a consequence, the transition from a feed-as-you-go to a hunting-gathering

strategy leads to a quantitative and qualitative improvement in the human diet,

having an economizing effect on the digestive system. This transition is in

line with the expensive-tissue hypothesis, which says that animals with cheap

guts can afford expensive (i.e., large) brains.

The development of the argument in chapter six is less clear than in other

chapters. The author attributes the origins of nepotistic exchange to the

larger pool of primate inheritance. Ofek believes that humans are a more

authentic representation of the common ancestral type than any other existing

species among the hominoid species (e.g., gibbons, orangutans, gorillas and

chimpanzees). The two major adaptive innovations of humans are the direct

feeding investment in mates and offspring by the male and the loss of overt

estrus and concealment of ovulation by the female. He also notes that another

important difference lies in the reproductive behavior of humans, which display

a diverse system of mating across cultures.

The natural history and social structures of the baboon are used in chapter

seven to better understand some conceivable early indications for the existence

of human exchange. The similarities between baboons and humans extend from diet

to anti-predator behavior. However, baboons maintain a degree of genetic

separation despite the absence of sharp geographical divides. Humans, on the

other hand, lost this capacity for adaptive radiation and gained capabilities

for adaptive specialization. Ofek argues that this was an inevitable outcome of

the introduction of trade as a principle of organization in human affairs.

Paleoeconomics is the subject of part two of the book, which deals more

explicitly with economic problems. Chapter eight explores the idea that trade

was instrumental for the transition from the feed-as-you-go strategy to

hunting-gathering. The main problem concerning the hunting-gathering strategy

is food sharing or redistribution. Ofek claims that the only way to make

economic sense of the food sharing for humans is to view it in the context of

some form of market exchange. This is due to the fact that all organisms that

rely on sexual reproduction have only two known options to redistribute the

output of hunting-gathering activity: eusociality or market exchange. However,

eusociality entails a lifestyle in which breeding is primarily limited to a

single reproductive female, which is not the way humans evolved.

In chapter nine Ofek puts forward the exciting hypothesis that contrived

commodities (characterized by exclusion and non-rivalry) provide an ideal

starting point to construct a model of early exchange. The two entities most

clearly identified as contrived commodities in prehistoric times are large game

and fire, since any additional consumer willing to pay can be accommodated at

no extra cost to the provider, and with no detraction in the consumption

available to others. Incidentally, the domestication of fire is the subject of

chapter ten. Ofek hypothesizes that fire by promoting trade was an agent of

evolution, and civilization. He makes interesting conjectures concerning three

important technical problems related to the domestication of fire: how to

create, contain and keep it.

Chapter eleven considers the upper Paleolithic creative explosion. According to

Ofek the refinement of upper Paleolithic tools suggests innovation in trade,

increased division of labor and improvement in market structures. The most

important and perhaps controversial conjecture of the whole book is that Ofek

associates trade with human migration. Specifically, he conjectures that the

incentives related to trade could be strong enough so as to justify migration

and long-term occupation of harsh environment, such as the migration during the

ice age from Asia to America.

The transition to agriculture is the object of chapter twelve. It is argued

that a necessary condition for agriculture is climate stability, however this

is not a sufficient condition. In chapter thirteen Ofek asserts that exchange

is the facilitating factor for the transition to agriculture, since exchange

reconciles the need for specialization in food production with the need for

diversification in food consumption. Exchange also explains the paradox of

husbandry (characterized by the fact that it takes more time and effort to

raise and slaughter a domesticated animal than to hunt and kill its wild

counterpart), as the meat obtainable from a domesticated stock is a highly

durable commodity because it comes into human possession in a live animal.

As seen above, Ofek’s book is in fact remarkable because it gives interesting,

exhausting and insightful answers to old problems and, at the same time, it

provides a new way to approach human evolution from the economic viewpoint. I

hope it will stimulate the research on the economics of prehistory.

Jo?o Ricardo Faria is the co-editor with Amnon Levy of Economic Growth,

Inequality and Migration, Edward Elgar, 2002, forthcoming. Among his recent

articles are “What Happened to the Neanderthals? – The Survival Trap,”

Kyklos 53(2), 2000, pp. 161-172; “Habit Formation in a Monetary Growth

Model,” Economics Letters 73(1), 2001, 51-55; and “Testing the

Balassa-Samuelson Effect: Implications for Growth and PPP,” (with M.

Leon-Ledesma), Journal of Macroeconomics, 2003, forthcoming.