1190 6 DECEMBER 2019 • VOL 366 ISSUE 6470 sciencemag.org SCIENCE
decryption. For example, in 1990 the U.S.
Central Intelligence Agency installed at its
headquarters in Langley, Virginia, a sculp-
ture in which artist Jim Sanborn encrypted
a message. Even the agency’s cryptographers
have yet to completely decipher it.
The book might have gone a tad deeper
and explained how digital messages con-
sist of binary numbers and how one can
be encrypted, for example, using a string of
random zeros and ones that only the sender
and the receiver share. Such a discussion
might have set up the chapter on internet
encryption more concretely.
But that’s a quibble. The book should in-
spire students who enjoy puzzles to invent
their own ciphers. As Caesar might have put
it, vjku dqqm ku c nqv qh hwp!
Can You Crack the Code? A Fascinating History
of Ciphers and Cryptography, Ella Schwartz,
Illustrated by Lily Williams, Bloomsbury, 2019, 128 pp.
George Washington
Carver for Kids
Reviewed by Monica Bradford^13
Most people remember George Washing-
ton Carver as a Black inventor who cre-
ated close to 300 peanut products. Peggy
Thomas’s book moves beyond that one-
dimensional view as she guides the reader
through Carver’s life story. Born in the
early 1860s to enslaved parents, Carver
overcame poverty and segregation to de-
vote his life to improving the livelihood
of impoverished Black farmers. Combin-
ing his early love of nature and painting,
Carver became a naturalist, an ecologist,
and a conservationist long before these
were valued disciplines.
Sprinkled through the book are 21 activi-
ties related to Carter’s life experiences and
the challenges he faced. Some of these easy-
to-follow activities encourage readers to act
like a naturalist by, for example, making
their own herbarium. Others allow readers
to experience tasks required for daily sur-
vival: turning a gourd into a bowl, cooking
with weeds, and making blocks like those
Carver used to construct a sod home.
As the first Black student to attend Iowa
Agricultural College (IAC; now Iowa State
University), Carver faced segregation and
isolation until an act of solidarity helped
break the ice with the other students and
faculty. The activity associated with this
event encourages readers to form a welcom-
ing committee for new students. Another
activity focuses on learning to deliver a
speech, a skill that Carver developed at IAC
and later used to teach farmers, politicians,
and leaders of industry about plants, soils,
and the potential of natural products.
Clearly, the knowledge Carver shared in
the early 1900s still resonates today. Hope-
fully, young readers will be inspired by his
resilience, thirst for learning, and passion
for improving lives.George Washington Carver for Kids:
His Life and Discoveries with 21 Activities,
Peggy Thomas, Chicago Review Press, 2019, 136 pp.YOUNG ADULT SCIENCE BOOKHow to Walk on Water
and Climb up Walls
Reviewed by Marc S. Lavine^14At the intersection of fluid, solid, and gaseous
flow; animal motion and mechanics; applied
mathematics; and robotics lies the research
of David Hu. Through stories about research-
ers he has interacted with over the course of
his career and a biographical view of his own
projects, Hu shows readers that we still have
a lot to learn about animal locomotion.
As humans, we are capable of traversing
a range of terrain, including mud, sand,
and rocky ground. We can move through
water or air. There are many animals, how-
ever, that excel in environments where we
struggle. The indestructible cockroach,
for example, not only can survive being
squashed to a quarter of its original height,
it will alter the shape of its legs so that it
can continue to move forward. It also has
antennae that it can move at full speed even
when surrounded by obstacles. These abili-
ties are reasons why the cockroach is used
as a model organism for the development
of inexpensive robots that might one day be
used in search-and-rescue missions in haz-
ardous environments.
The combination of fluid mechanics and
animal physiology helps explain the optimal
length of eyelashes for filtering out debris,
flying snakes that glide efficiently with no
wing or web structure, and how ants form
robust collective rafts. However, the study
of motion goes beyond the movement itself.
Animals such as lamprey reveal how motion
can be controlled, not by a brain but by a
series of central pattern generators that are
sets of small interacting periodic motions.
This allows a salamander to change from a
walking motion to a swimming one just by
altering the speed of the lead oscillations.
Studying animal motion in fine detail may
seem wasteful to many, but as Hu convinc-
ingly shows, a detailed understanding of the
interaction between biology and fluid me-chanics is interesting in its own right and a
rich source of design and engineering ideas.How to Walk on Water and Climb up Walls:
Animal Movement and the Robots of the Future,
David L. Hu, Princeton University Press, 2018, 238 pp.Never Home Alone
Reviewed by Andrew Sugden^15Although you may encounter reminders of
life that flourishes outdoors—the occasional
spider in the bath, the mold that sometimes
sprouts on food—by and large, the only liv-
ing beings you consciously encounter in
your home are the other people in your life
and your pets. After reading this book, you
will probably see things quite differently.
Our homes are teeming with life. A mi-
crobial analysis of household dust samples
from just 40 homes in North Carolina
yielded nearly 8000 different microbial
taxa, for example. Household microbial
communities vary by habitat: As Rob Dunn
writes, “...samples from pillowcases and toi-
let seats are different from each other, but
perhaps not as different as you might hope.”
Larger creatures are often hiding in plain
sight as well. Dunn describes surveys of the
arthropod communities in homes around
the world. His own house was home to at
least 100 arthropod species—mainly flies
and spiders—and worldwide, the numbers
of species stretch into the thousands.
Dunn considers how human history (and
prehistory) may have shaped the microbial
communities that have evolved to share our
lives. He delves into research that enumerates
the health benefits to humans of closer con-
tact with natural biodiversity and, conversely,
the problems that arise through the evolution
of pathogens resistant to control measures.
Perhaps above all, this book is a vehicle for
conveying the story of how science is done—
the quirks and collaborations that lead from
one discovery to another, and the role of citi-
zen science in advancing knowledge.Never Home Alone: From Microbes to Millipedes,
Camel Crickets, and Honeybees, the Natural
History of Where We Live, Rob Dunn, Basic Books,
2018, 330 pp.Superheavy
Reviewed by Nathaniel Smith^16Kit Chapman begins his story of the early
hunt for so-called “superheavy” elements
with Enrico Fermi, the scrappy Italian physi-
cist who claimed, erroneously, to have discov-
ered elements 93 and 94. As the first scientist
to develop a technique for a phenomenonINSIGHTS | BOOKS
Published by AAASon December 12, 2019^http://science.sciencemag.org/Downloaded from