These are the most frequently used words in this book.
almost
animals
another
apes
baby
behavior
beings
between
body
brain
called
cannot
cause
change
children
chimpanzees
come
culture
development
difference
different
disease
does
during
effect
environment
even
experience
experiment
fact
family
far
few
find
first
form
found
genes
genetic
get
good
hand
human
idea
instinct
language
later
learning
least
less
life
little
long
male
man
may
men
might
mind
monkeys
mother
must
nature
neurons
new
now
nurture
own
parents
part
people
percent
perhaps
personality
rather
result
right
schizophrenia
see
seems
set
sex
similar
social
something
species
still
studies
take
theory
things
though
time
twins
two
words
work
world
years
yet