2014). Health-related aspects of human evolu-
tion are the subject of Evolutionary Medicine
by S. C. Stearns and R. Medzhitov (Sinauer,
Sunderland, MA, 2016). A very readable and
personal account of the Neanderthal genome
project is Neanderthal Man: In Search of Lost
Genomes (Basic Books, New York, 2014) by
Svante Pääbo, the project’s leader. Pääbo’s
article “The human condition—a molecular
approach” (Cell 157: 212–226, 2014) reviews hu-
man evolution from a genetic perspective. A
recent review of the fascinating story of how
humans colonized the planet is “Tracing thepeopling of the world through genomics,”
by R. Nielsen, J. M. Akey, M. Jakobsson, J. K.
Pritchard, S. Tishkoff, and E. Willerslev (Nature
541: 302–310, 2017).
A valuable introduction to cultural evolution and
gene-culture coevolution is Not by Genes
Alone: How Culture Transformed Human Evo-
lution by P. J. Richerson and R. Boyd (Univer-
sity of Chicago Press, Chicago, 2005). A broad
variety of articles on cultural evolution is found
in Philosophical Transactions of the Royal Soci-
ety B, vol. 336, issue 1567 (April 12, 2011).PROBLEMS AND DISCUSSION TOPICS
- What evidence shows that the most recent com-
mon ancestor of chimpanzees and humans was
much more arboreal than modern humans are?
What changes in environmental conditions in
Africa might have selected for a less arboreal
lifestyle in the human lineage? Why did the
same changes not evolve in the chimpanzee
lineage? - How has the effective population size of humans
changed over the last 100,000 years? How have
these changes altered the relative contributions
that natural selection and genetic drift make to
human evolution? - The first modern humans evolved in Africa. Give
two kinds of evidence that support that conclu-
sion, one based on data from living individuals
and one from some other source of data. - Discussions of human ancestry sometimes refer
to the “Mitochondrial Eve” and “Y-chromosome
Adam.” Who were these individuals, and why do
they have those names? Did they live in the same
place and at the same time? Explain. - Many people assume that modern medicine has
eliminated natural selection in humans. What
are three traits that are currently under natural
selection in one or more human populations?
What form of selection is acting on those traits?
What kinds of data show how selection is act-
ing? You might consider examples discussed in
other chapters in addition to those described in
Chapter 21.
6. Neanderthal fossils were first discovered in the
nineteenth century. Study of their morphology
suggested that Neanderthals were more closely
related to humans than any living species of
primate was. Much later, it became possible to
sequence DNA from Neanderthal fossils and
compare the sequences to those from other pri-
mates. Did the results confirm or refute the ear-
lier conclusions based on morphology? Explain.
7. What did Jared Diamond mean when he called
agriculture “the worst mistake in the history
of the human race”? Provide arguments both
against and in favor of this statement.
8. Humans spread out of Africa and across the rest
of Earth starting about 60,000 years ago. As
they did so, species that are commensals and
parasites on humans spread with them. What
geographic patterns might you expect to see in
the genetic variation of those species?
9. The “aquatic ape hypothesis” is a discredited
hypothesis about human evolution. It proposes
that several features of the modern human phe-
notype (including hairlessness, upright posture,
and subcutaneous fat) result from descent from
a semiaquatic ape that was adapted to life in
shallow water. Research the aquatic ape hypoth-
esis and explain why it has been rejected by
anthropologists.
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