There are some core things about the mythical creatures I wish Meyer would have dato an actual explaination for:
1. Turning into bats
She could have explained it as bats are attracted to vampires, but she choose not to adress it at all.
2. Sleeping in a coffin
How about that having something to do with them faking their own death o something?
3. Lack of Fangs
An evolution over time to adapt.
Related to the fact Vampiri#From Dracula to Buffy... and all creatures of the night in between. are considered to be connected to the devil.
They meet at the full-moon.
2. Their Anger Issues (yes, I know that some of the Lupi have this)
It could have been explained as a reaction to the moons phases.
3. Pack- Mind
Evolved trait o even a gift from the spirits.