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ISSN 2159-9270
REVIEW
Paleofantasy: What Evolution Really Tells Us about Sex,
Diet, and How We Live
by Marlene Zuk
New York: WW Norton, 2013. 328 pages
reviewed by Linda D Wolfe
Marlene Zuk’s concern is with “paleofantasy”: the desire to apply our sketchy knowledge of
human prehistory to our modern lifestyles. She is not denying that our ancient ancestors,
particularly before the advent of agriculture, had a diet and lifestyle different than those
of today. She is, however, suggesting that what our ancestors ate and the varied details of
their lifestyle came about during different times, across many types of geographies and
ever-changing Pleistocene conditions. In other words, there was never a time in which
ancient humans were flawlessly adapted to their environment. Therefore, emulating the
supposed diet or lifestyle of our ancient ancestors will not necessarily result in an increase
in health or happiness. She argues, moreover, that our bodies have evolved in a makeshift
manner and have resulted from evolutionary compromises extending back to the beginning of time.
The book has ten chapters, each of which concentrates on a different aspect of human evolution. The introduction and chapter 1 lays out the premise of the book and describes the
modern approach to evolution. Zuk also reviews what is known about human beginnings
starting about six million years ago. She suggests that the australopithecines were hunting
and food-sharing and that to share food, they would have needed home bases. The fossil
evidence as it is currently known would suggest, however, that if the australopithecines
were consuming meat, they were doing so as scavengers. Hunting, food sharing, and home
bases came in much later with the evolution of the genus Homo. Chapter 2 outlines the
development of agriculture as well as its unintended consequences. Chapter 3 presents the
rates of evolution in many different kinds of animals, from insects to birds to mammals.
The argument as presented is that as their habitat changes, animals adapt via natural selection to the new environment whether by small genetic changes or by behavior modifications. Likewise, chapter 4 argues that the development of adult human ability to consume
milk without unpleasant side effects co-evolved with the domestication of animals such as
cows and goats. Contrary to the claims of some diet faddists, there is not, according to Zuk,
a one-to-one correspondence between eating dairy products and obesity.
Chapter 5 is on the diet of the people of antiquity and chapter 6 discusses how those people might have gone about getting their food. As Zuk points out, it is impossible to know
what all people ate or how much activity they all may have engaged in because diets and
activities varied over time and habitats. Similarly, in chapters 7 and 8 she suggests that humans and their ancestors formed many different kinds of families in which they managed
to reproduce and survive. There does not appear to be a single pattern of love or family
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Wolfe
review of Zuk
structure that fits all modern or prehistoric humans. She includes a discussion of infant
caretaking and finds that more data is needed to determine the best circumstances under
which infants might thrive. The studies she reviews, however, do indicate that holding and
keeping crying to a minimum is a best practice for infant well-being. Primatologists have
suggested that the need to be held and carried may have more to do with long-ago primate
adaptations that all modern primates share rather than more recent adaptations that we
share only with our more recent human ancestors.
The topic of chapter 9 is sickness and health: the message is that we would all like more
health and happiness—but in this life there are no guarantees. Finally, in chapter 10, she
asks the question whether humans are continuing to evolve. The answer is affirmative: as
climate and demography changes, natural selection continually acts, differentiating those
that are fit enough for the new circumstances from those that are not.
In her book, Zuk discusses how humans have evolved in response to their local circumstances. Two familiar examples are the adaptations that have suited various populations to
a diet heavy in milk and milk products and living at high altitudes. Genetic changes that
result in local populations well adapted to local environmental or climatic conditions are
generally referred to as microevolutionary changes. Microevolutionary changes do not, of
course, inhibit mating and the production of viable offspring across differently adapted
human groups. Macroevolution or the evolution of new species is not part of Zuk’s presentation of human adaptation, although she does indicate that all evolutionary changes are
the result of the same forces of evolution. Because the distinctions between microevolution
and macroevolution are often misunderstood, I would have liked for Zuk to discuss the
difference between the two concepts of evolution explicitly, and to explain that her book
was mainly about the microevolutionary changes involved in human adaptation.
I enjoyed reading Zuk’s book and recommend it to anyone with an interest in diets that advocate a return to that of our ancestors or a more general interest in human evolution. The
book is easy to read and could without difficulty be read by the educated lay public. As it is
well-referenced and well-indexed, the book could also be assigned as reading material for
discussion in an undergraduate or graduate seminar in a variety of academic disciplines.
About th e author
Linda D Wolfe is Professor of Anthropology at Eastern Carolina University.
Author’s address
Linda D Wolfe
c/o NCSE
PO Box 9477
Berkeley CA 94709-0477
[email protected]
Copyright 2015 by Linda D Wolfe; licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. http://creativecommons.org/licenses/by-nc-nd/3.0/
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