How could modern day humans evolve into two different species? Come up with a future scenario and explain why it
would result in two different species of humans.

Color blindness is a recessive trait. the gene for color blindness is on the x chromosome. the family tree below shows the trait of color blindness. the only unknown is the mother in the first generation

How can antibodies "remember" a particular bacterial invader or "antigen" on that invader?

Earth is tilted on its axis. which of these would not exist if earth had no tilt?