I have a third cousin who looks identical to me (the family would bring her photo out when I was young to show visitors and say this is Amanda and they all believed it, and then laughed). I studied the photo, we were identical, the teeth were exactly the same. She was 4 years younger than me. This was’nt just a look alike, it was more identical than that. What reason would there be to us being so identical ?
OLIVE TREE ANSWER: Dear Amanda,
It's called genetics.
Each of us is made up of genes passed on from our parents, their parents, their grandparents and on and on back in time. This is also called hereditary transmission, meaning the characteristics that come from the DNA we inherit from our ancestors.
Think of it like an alphabet soup. You're a bowl of unique alphabet soup (each of us is) but in your case your cousin got pretty much the same mix of letters. There'll be differences in her soup but the two of you got enough of the same letters in your bowls to resemble each other.
For a scientific explanation you will have to visit a few sites. Just google DNA or GENETICS and see what pops up.