Size does matter!

When I interned at Florida Aquarium I had the pleasure of working with two screech owls. Sure, there were bigger, more impressive looking raptors that I could hold and show people, but those pint-sized versions were my favorite. It wasn't just that they were small (though that totally helped). It was that when you'd go to take them out of their cage to walk around with, they would puff up and try to act all big an menacing - which, frankly, just made them look like giant brown cotton balls.

What the birds were aiming to do was make themselves look bigger and more important. All kinds of animals have similar tricks to improve their size, which in turn reflects on their status. Whether it be to scare off rivals for their territory or impress the ladies, in the animal kingdom, size does matter. And humans, the hairless apes that we are, are no different.

It's long been known that size is associated with status. After all, we "look up" to people of power and authority. Taller people are more likely to be leaders, attract mates, be healthy, live long and be more intelligent. Just think of the quintessential ideal or model male and female - neither is anywhere near average height. Even where height seems less important, like in generally shorter cultures, overall size is still big. Sumo wrestlers, for example, are considered to be high status individuals, and the kings and upper class of Polynesian cultures flaunted their wealth with their waistlines. It's uncertain whether the bias exists because of some genetic link between size and admirable traits or if being tall or large is like colorful plumage in birds - attractive because it puts the person in danger or is energetically costly, thus impossible for unhealthy, unfit people to achieve. But what is certain is that bigger is better.

What's even more interesting is that perception of size is strongly linked to status. That's what a very interesting study, published in PLoS ONE, has shown experimentally. Not only did people think taller-looking people were higher status, they thought that those who displayed higher status traits were taller and heavier.

To probe the relationship between status and size, the researchers from Georgetown University and the NIH used a set of experiments which asked participants to guess the relative dominance, age, height and weight of actors in photos. The actors were manipulated into different poses, one which portrayed a high, authoritative status, one which portrayed a low, submissive status and one which was neutral. Poses were also either sitting or standing or in between. High status poses included lowered brows, open body postures, eye contact and outward-directed gestures like pointing, whereas the submissive poses had raised brows, averted eyes, closed postures and self-directed gestures like touching one's own body. Some of the photos were altered to make the actor look larger by making other objects in the photo smaller.

What they found was that, unanimously across the board, people that looked taller were perceived as more dominant. Even the same actor in the exact same pose, with simply a change in the background to make him look shorter, looked less dominant. But even more amazingly, the status implied by the posture an actor took, whether sitting or standing, affected how tall they appeared to the participants. Actors in authoritative status poses were judged to be on average an inch taller and 5 lbs heavier than when they were in submissive ones, whether sitting or standing.

Part of the effect, the researchers found, is due to silhouettes. When we're in certain poses, we look like we take up more space - literally. By analyzing the pixels in a 2d manner of different poses, the researchers found that we, in effect, are larger when we're in dominant positions. As the authors explain, "Although the targets' actual size did not vary across poses, in the sense that their actual height and weight were unchanged, the targets' apparent size in the two-dimensional plane visible to a perceiver varied significantly."

This is the first study which has shown that these status cues, like open or closed posture, directly impact perceived size. The authors speculate that like other animals, we, too, have evolved behaviors which change the appearance of our size as ways of gaining or losing status in a situation. These cues are picked up by low-level perceptual processes, not by higher order rational thought, but have a big impact on how we see a situation or judge a person. While we can't actually make ourselves taller or heavier, we can make ourselves appear to be so, and by doing so, affect how other perceive us. Though hopefully we're a bit more effective in our efforts than those little screech owls were - I definitely wasn't scared one bit by their tough guy acts.

Marsh, A., Yu, H., Schechter, J., & Blair, R. (2009). Larger than Life: Humans' Nonverbal Status Cues Alter Perceived Size PLoS ONE, 4 (5) DOI: 10.1371/journal.pone.0005707