Science Confirms: Yes, There’s a Butt Crack Bias

Thursday February 6, 2025.

In the ever-evolving quest to understand human attraction, a new study published in Aesthetic Plastic Surgery has confirmed what many have long suspected: when people look at a female butt, their eyes are magnetically drawn to one place first—the intergluteal cleft, better known as the infamous butt crack.

Because this research is so vital for understanding the course of human destiny, researchers, (using eye-tracking technology), analyzed the subconscious visual habits of men and women when presented with images of female buttocks.

The findings? No matter the gender, people just can’t help but take a peek at the crack.

However, men and women have slightly different preferences when it comes to other rear-end details.

Why Scientists Are Studying Butts (Yes, Really)

In an era where Brazilian Butt Lifts (BBLs) are booming and the demand for sculpted curves has gone global, researchers wanted to understand exactly which aspects of the derrière catch people’s attention.

What makes a “perfect” butt in the eye of the beholder? And are these preferences different across genders and cultures?

To get some answers, researchers recruited 67 heterosexual volunteers (28 men and 39 women) ranging in age from 20 to 59, with an average age of 27.7 years.

Participants gave informed consent—presumably after nervously asking, “Wait… so I’m just staring at butts for science?”—and then had their eye movements recorded using infrared-based eye-tracking technology.

Each subject viewed standardized images of seven female models from multiple angles—straight-on, oblique, and side views—while the device recorded exactly where their gaze landed, how quickly they looked at certain areas, and how long they lingered.

Breaking Down the Butt: What Gets the Most Attention?

To get ultra-specific (because science demands precision when studying butts), researchers divided the derrière into ten different "areas of interest":

• Intergluteal cleft (a.k.a. the butt crack)

• Upper medial buttock

• Lower medial buttock

• Upper lateral buttock

• Lower lateral buttock

• Lumbar area (lower back)

• Hip dip (curved area below the hip bone)

• Lateral thigh

• Gluteal fold (crease where the butt meets the thigh)

• Thigh gap

The results?

The intergluteal cleft was the clear winner, commanding the most visual attention regardless of gender or ethnicity, with an average fixation time of 0.87 seconds.

Meanwhile, the thigh gap barely got a second glance, receiving a mere 0.06 seconds of attention—proving once and for all that thigh gaps may be a social media obsession, but not a biological one.

Men vs. Women: Different Butt-Viewing Strategies?

While both genders agreed that the butt crack was the main event, men and women showed some notable differences in their gaze patterns:

• Men stared at the intergluteal cleft longer (0.96 seconds on average) compared to women (0.81 seconds).

• Women were more interested in the upper lateral buttock, lumbar region, and gluteal fold—areas that contribute to shape and curvature.

• Men spent more time on the hip dip, possibly because of its association with waist-to-hip ratio, a well-documented marker of attraction.

In terms of which area caught their attention the fastest, the lower medial buttock won, attracting a gaze within 1.47 seconds, while the thigh gap took the longest (2.52 seconds), making it the least interesting feature in real-world observation.

Cultural Differences in Butt Appreciation

Interestingly, gaze patterns varied by ethnicity:

• Asian participants spent more time analyzing the lower medial buttock and hip dip.

• Caucasian participants locked onto the intergluteal cleft and hip dip more quickly.

These findings hint that cultural aesthetics may subtly shape our subconscious preferences—even when it comes to something as universal as the human butt.

Does More Staring = More Attraction? Not So Fast…

Before we declare the butt crack the reigning champion of beauty standards, the researchers caution that more staring does not necessarily mean higher attractiveness.

A longer gaze could indicate curiosity, surprise, or even confusion rather than aesthetic appreciation.

Also, for those wondering—yes, the models in the images were wearing a black thong, which could have influenced where participants' eyes landed. (Because let's be honest, contrast and framing matter.)

What’s Next? The Future of Butt Research

Scientists aren’t done scrutinizing the posterior quite just yet. Research will continue to probe our posterior preference.

Future studies aim to connect gaze patterns with subjective attractiveness ratings, determining whether prolonged fixation translates into actual preference—or if some areas just command attention out of sheer visual intrigue.

One thing’s for sure: whether you’re a scientist or a casual observer, human attraction remains a hot research area. In other words, the sh*t we spend research dollars on sometimes utterly stupefies me.

Be Well, Stay Kind, and Godspeed.

REFERENCES:

Zeng, R., Glaue, E., Moellhoff, N., Alfertshofer, M., Cotofana, S., Knoedler, S., Knoedler, L., Wiggenhauser, S., Giunta, R., & Frank, K. (2025). Eye-tracking insights into the perception of buttocks. Aesthetic Plastic Surgery.

Buss, D. M. (2019). Evolutionary psychology: The new science of the mind (6th ed.). Routledge.

Fink, B., & Penton-Voak, I. S. (2002). Evolutionary psychology of facial attractiveness. Current Directions in Psychological Science, 11(5), 154–158. https://doi.org/10.1111/1467-8721.00190

Hewig, J., Trippe, R. H., Hecht, H., Coles, M. G. H., Holroyd, C. B., & Miltner, W. H. R. (2008). Decision-making in Blackjack: An electrophysiological analysis. Cerebral Cortex, 18(2), 464–470. https://doi.org/10.1093/cercor/bhm078

Holzleitner, I. J., & Perrett, D. I. (2017). Perception of strength from 3D faces is dependent on viewing angle. Frontiers in Psychology, 8, 2256. https://doi.org/10.3389/fpsyg.2017.02256

Johnston, V. S., Hagel, R., Franklin, M., Fink, B., & Grammer, K. (2001). Male facial attractiveness: Evidence for hormone‐mediated adaptive design. Evolution and Human Behavior, 22(4), 251–267. https://doi.org/10.1016/S1090-5138(01)00066-6