Tom Smulders does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment. Most of us have spent a considerable part of our life looking for true love – our perfect match. The search for an ideal partner isn’t exclusive to humans, many animals do it too. But from an evolutionary perspective it is not actually clear why we couple up at all. Why spend time and effort on being fuzzy when we could be reproducing? Now a new study in birds has shed some light on this long-standing problem, suggesting there are actually evolutionary benefits from finding the ideal mate. The findings may apply to humans, too. So how do you know who your perfect partner is? The answer seem to change from species to species. Because females usually invest more in reproduction than males, they tend to be the choosier sex. Often, there is broad agreement on which males are the most desirable. These males either provide superior resources, such as really good territory, or superior genes that guarantee healthier offspring. In humans too, there are some individua...