Love, lust, and everything in between is surrounded by sonnets, lyrics, and sappy romance — but what’s really happening inside your body is more of a science than you’d think. Within seconds of coming into contact with a potential mate, your entire body begins to play matchmaker and secretes hormones, while your brain calculates attraction. You begin to weigh, measure, and evaluate the person by engaging all five senses on beauty, natural scent, voice, physical contact, and the taste of their kiss.

With advancements in technology, medicine, and societal norms, it’s become easy to forget humans are still animals in search of a quality reproductive partner. Long hair and scar-free skin are both signs of a healthy and fertile mate, which can be one of the signifiers of initial attraction. However, there are a wide variety of visual cues, anywhere from cultural preferences to beauty standards.

The nose knows. It’s not your perfume or cologne it’s attracted to, but instead the type of pheromones secreted from sweat and other bodily fluids that have the power to trigger sexual interest. Ovulating women give off stronger natural scents, and studies have shown men are more attracted to a woman during that time of the month.

After passing through these two stages, hearing your potential match speak could make or break the pairing. Men prefer high-pitchy, breathy voices in females, while women are drawn to deeper voices with closely spaced wording. When you reach an outstretched arm to laugh at a joke they just made, the temperature and smoothness of their skin will either bring you to the next step or have you ready to back away.

If they’ve made it through all of the matchmaker stimuli, the first kiss will either seal the deal or kill the mood. In surveys, a majority reported they’ve lost attraction to someone due to a bad first kiss. When the combination of smell and taste pass the test, the body secretes norepinephrine to give you tunnel vision and focus, while an increase in glucose supplies additional energy, giving you those jittery butterflies in your stomach.