DAVIS (CBS13) – Knowing on the first date that you’ve met the person you’re going to marry might be more fantasy than fact, according to a new study done by UC Davis.

Researchers surveyed more than 800 people of all ages and found long and short-term relationships actually look almost identical in the beginning. The trajectories typically don’t pull apart until you’ve known the person for weeks or months- around the time relationships become sexual.

The lead author, Paul Eastwick, is an associate professor of psychology at UC Davis. He and his team surveyed people and asked them about the events and experience in past short-term and long-term relationships, specifically the events in the very beginning- before they even started dating. They broke the events up into a number of categories, including: first time they held hands, met each other’s parents, said “I love you”, first planned a vacation, first had a major disagreement, first lied, and first became annoyed with the other person.

“Some of the most interesting moments in these relationships happen after you meet the person face-to-face, but before anything sexual has happened,” said Eastwick. “You wonder ‘is this going somewhere?’ or ‘How much am I into this person.’ It is somewhere around this point that short-term and long-term relationships start to diverge, and historically, we have very little data on this particular period of time.”

In the beginning, the romantic interest rises at about the same rate. In short-term relationships it tends to plateau and then decline, according to researchers. In longer term relationships the romantic interest ascends and reaches a higher peak.

The researchers concluded people end up in short-term relationships when they’re attracted to each other enough to keep having sex. Long-term relationships start out exciting and sexy and end up stable and lasting.

The results were published in the Journal of Experimental Psychology: General.