You're cruising down I-75 in your new compact, Florida-bound, when you glance at the rearview mirror - GULP! You're being tailgated! We're talking "expressway ecology" and that big tractor-trailer is at the top of the food chain. The wood duck is cruising through a slough in Florida when he glances aft - GULP! He's being tailgatored! Now we're talking "Everglades ecology" and that big lizard is at the top of the food chain. Will you arrive alive on I-75? Is it safer to fly?