These are the most frequently used words in this book.
altruism
among
animal
another
behavior
between
children
come
common
course
darwin
darwinian
day
does
environment
even
evolution
evolutionary
example
fact
feel
feelings
female
find
first
friends
genes
genetic
get
good
great
help
human
indeed
interest
investment
kind
least
less
life
likely
long
love
male
man
marriage
may
men
might
mind
moral
natural
nature
new
now
offspring
often
once
others
own
parents
part
people
person
point
question
reason
reciprocal
right
say
see
seems
selection
sense
sex
sexual
should
social
society
sometimes
species
status
still
theory
things
though
thus
time
toward
two
values
victorian
view
whether
without
woman
women
work
wrote
years