The new study from Stanford University aimed to look at the idea that “long-term partners’ facial appearance converges with time due to their shared environment, emotional mimicry, and synchronized activities.” The researchers examined pictures of 517 couples at the beginning of their marriages and then again 20 to 69 years later. Then, the Stanford researchers used human judgment and facial recognition software to assess the similarities. The researchers gave participants—and fed the software—a picture of a “target” person and six other pictures, one of which was the target’s spouse. The respondents and technology then determined how similar they thought each of the six faces was to the target picture. Both the humans and the technology frequently selected the married pairs as having the most striking resemblances.ae0fcc31ae342fd3a1346ebb1f342fcb The Stanford researchers did not find any evidence to support the notion that partners grow more similar in appearance as they age, but what they did deduce is that couples do resemble each other when they meet. This discovery “brings facial appearance in line with other traits—such as interests, personality, intelligence, attitudes, values, and well-being—which show initial similarity but do not converge over time,” the authors note. Translation? You’re most attractive to someone whose face looks like yours. Another study published in the journal PLOS One in 2013 also found that people were more attracted to those who resembled them. The study generated pictures of the participant’s partner’s faces altered to include some features from another face—either a random face or the participant’s face. The subjects consistently rated the face that included aspects of their own face as the most attractive. Researchers say this happened on a subconscious level, as participants were not able to identify the presence of their own faces in the pictures. This newer research debunks an oft-referenced 1987 study published in the journal Motivation and Emotion that asserted that after 25 years of cohabitation there is an increase in physical similarity among couples. During this study, researchers only compared pictures of about a dozen couples at the beginning of their marriage and 25 years later to assess physical similarity. RELATED: For more up-to-date information, sign up for our daily newsletter. These new reports shed light on why you may find yourself squinting your eyes at a couple as you try to discern if they’re related or dating. That includes the countless celebrity couples who resemble each other, from Tom Brady and Gisele Bündchen to Jessica Alba and Cash Warren. It turns out, being attracted to someone who has similar physical attributes as you is not strange—it’s just science. And if you’re concerned for the state of your partnership, check out Half of Men Say They Would Break Up With a Woman Who Does This.