I understand the evolutionary benefit of a heart beating faster and senses improving when in a dangerous situation. The body is getting ready to run from the tiger. But what is the evolutionary point of the butterflies-in-stomach feeling when you have a crush on someone? What possible benefit is there?
Social interaction has transcended evolution in some senses. We don’t really know when cavemen felt butterflies (or simple nervousness, to put it in simple terms). Maybe it’s just part of the trepidation sensation, which indicates that something important is happening, and you need to pay attention.
Can we really separate the “I’m talking to a hot girl” trepidation from “it’s a dark scary cave, I wonder if there are dinosaurs in there” one?
On the basic, physiological level reactions to stress aren’t that differentiated. It doesn’t matter if you are excited because you spotted prey, mate of predator - either of this situations potentially need you to squeeze more power from your body and hence faster heartbeat, pressure up etc. We give meaning and differentiate this situations using our neocortex, but older parts of brain, not to mention glands, see them as similar. So, upon seeing your crush your modern brain see situation as potentially scary or stressful - and sends red alert downward, without note on the kind of stress attached.
Unless it changes the chance of you having a baby, evolution doesn’t really care.
Why are you assuming there’s an evolutionary benefit?
Getting ‘butterflies’ or a ‘nervous stomach’ apparently does not negatively affect one’s ability to reach reproductive age, reproduce and have fertile off-spring.
One could then argue that there could be a list of things that could be advantageous about the butterflies, in that proceeding with caution and reacting to the dump of adrenaline protect one’s well being and that anyone with such feelings has an increased likelihood off living longer and reproducing more.
Evolution doesn’t do anything for a ‘reason’.
I had a college professor who stated that a nervous stomach is an advantage because it is easier to fight or flee an attacker on an empty stomach. That is a nervous stomach may cause a person to vomit.
Either you are a fundamentalist Christian, or have been watching too many episodes of “The Flintstones”.