These are the most frequently used words in this book.
ancestor
animals
another
argument
arms
bats
between
body
book
brain
called
case
cells
change
chapter
come
computer
different
dna
does
down
effect
even
evolution
evolutionary
example
eye
fact
far
females
first
fossil
generations
genes
genetic
get
good
happen
human
idea
individual
instance
itself
kind
know
large
life
living
long
males
may
means
might
million
molecules
must
mutation
natural
new
now
number
own
part
particular
point
possible
process
race
random
rate
rather
really
reason
say
see
seem
selection
sense
shall
should
single
small
something
species
step
still
tail
take
theory
things
think
time
tree
true
two
use
whole
words
world
years