F. Most tropical species prefer the top half of that range, and most temperate zone snakes like the bottom half. A temperature gradient in the cage lets the snake decide how warm it wants to be. A thermometer can be the herper's best friend because a snake won't eat if it's more than a few degrees below optimum temperature. Snakes have a day-night temperature cycle in the wild. Some studies indicate that if a reptile is constantly held at optimum temperature for weeks, it suffers heat stress.
Males also have the sperm killed.
It is probably best for a snake to spend the night at a temperature 5 to 20 degrees F below its daytime activity temperature. Cages should be of adequate size, easy to keep clean, adequately ventilated, and escape proof. Aquariums with pegboard tops make good cages. Plastic shoe boxes and storage boxes also make good cages after enough air holes have been cut in them. Big cages can be made of wood and pegboard, but not wire mesh or screen because a snake can rub its nose raw on wire.