106
- FROM FINS
TO FINGERS
TETSUYA NAKAMURA,
EVOLUTIONARY
DEVELOPMENTAL
BIOLOGIST AT
RUTGERS UNIVERSITY
At some point in the
course of animal evo-
lution, small bones in
fish fin rays became
the relatively larger
ones that make up
human fingers and
wrists. Our lab found
each very different
appendage actually
contained the same
exact type of cells.
4. HEARING EVERY
LAST NOTE
ANDREA STREIT,
DEVELOPMENTAL
NEUROBIOLOGIST
AT KING’S
COLLEGE LONDON
The ear’s visible
folds capture nearby
noise, but tiny hair
cells inside help turn
that seized sound
into recognizable au-
dio. They are fragile,
though. Unlike fishes
and birds, when ours
(and all mammals’)
get damaged, they
are ruined for good. - DESIGNED
FOR SMIZING
DANIEL LIEBERMAN,
HUMAN EVOLUTIONARY
BIOLOGIST AT
HARVARD UNIVERSITY
The area that
surrounds the
iris—called the
sclera—is tinted in
most animals but
bright white in hu-
mans. This allows us
to see where others
direct their gazes,
enabling crucial si-
lent communication
like eye rolls and
sideways glances. - THESE KNEES WERE
MADE FOR WALKING
TERENCE CAPELLINI,
HUMAN EVOLUTIONARY
BIOLOGIST AT
HARVARD UNIVERSITY
It’s not easy to find
an efficient way to
walk on two legs.
Once we landed on a
shinbone, knee, and
thigh bone configura-
tion that worked, we
stuck with it. Every-
one complains about
knee pain. Evolution
made something op-
timal, but it did not
make it everlasting. - A BREATH OF
WARM AIR
ARSLAN ZAIDI,EVOLU-
TIONARY GENETICIST
AT THE UNIVERSITY
OF PENNSYLVANIA
Climate likely plays
a role in how noses
formed. Our schnoz-
zes filter air to make
it warm and moist for
our lungs. Wider
nostrils prevent
overheating, while
narrow nasal holes
more easily moistur-
ize frigid, dry air.
Evolution had to
strike a balance.
TALESFROM THEFIELD SPRING 2020 / POPSCI.COM
why we look
the way we do
as told to Ellen Airhart