An Imgurian with the username HeavyBro has made a lasting contribution to the frontiers of Imgur and Internet science with an amazing post that, believe it or not, does a pretty good job explaining the biological characteristics of "a great butt."
Evolutionary scientists maintain that much of what we find attractive in others stems from the biological imperative to reproduce and have healthy, strong offspring. What does that have to do with butts? Well, you're about to find out.
HeavyBro's post contains actual facts confirmed by evolutionary biologists. 'Plumpness,' for example...
Estrogen is one of the dominant factors in adipose tissue accumulation: estrogen causes fat storage in the hips, thighs, and buttocks. women, thusly, carry more fat (it's not a bad word!) in areas that men don't.
According to Victoria Pitts-Taylor in The Cultural Encyclopedia Of The Body, evolutionary psychologists have hypothesized that plump buttocks have "evolved as a desirable and attractive characteristic for women in part because this rounding clearly signaled the presence of estrogen and sufficient fat stores to sustain a pregnancy and lactation."
Some scientists, however, disagree. In a study done by T.M Caro of the University of Michigan says that fat storage in the buttocks and breasts may have "no signal function at all."
As for IQ, we'll get to that momentarily.
2. What about perkiness?
Again, "perkiness" is thought of as a visual indicator of youth, fertility, and fecundity. The fact of the matter is that as we age, we sag: Men and women are both subject to the time's ability to turn us, seemingly overnight, into people we scarcely recognize in the mirror. Perkiness is the stuff of youth, try as we might to preserve it.
3. Spine angle.
Citing a University of Texas at Austin study run by psychologist David Lewis, Neuroscience News reports that men in the study "were most attracted to images of women exhibiting the hypothesized optimum of 45 degrees of lumbar curvature."
"This spinal structure would have enabled pregnant women to balance their weight over the hips," Lewis asserted. "These women would have been more effective at foraging during pregnancy and less likely to suffer spinal injuries. In turn, men who preferred these women would have had mates who were better able to provide for fetus and offspring, and who would have been able to carry out multiple pregnancies without injury."
We're about to get a little NSFW, so please be advised.
4. Body fat (told you it's not a bad word).
Let's review what we've looked at so far from an evolutionary psychology standpoint: the presence of visible body fat may "signal" health and fertility.
Moreover, gluteofemoral fat (the tissues around the buttocks) may play a role in prenatal brain development. A study by William D. Lassek of the University of Pittsburgh found that "gluteofemoral fat is the main source of long-chain polyunsaturated fatty acids (LCPUFAs), especially the omega-3 docosahexaenoic acid (DHA), that are criticalfor fetal and infant brain development" and that a "study in England shows a similar positive relationship between a mother's prenatal consumption of seafood (high in DHA) and herchild's verbal IQ."
5/6: Hip width and waist diameter.
Again, we turn to Pitts-Taylor in discussing hip width: "...the buttocks (as a prominent secondary sex characteristic) are thought to have served as a visible sign or clue to the size and shape of the pelvis, which has an impact on reproductive capability, especially in women."
As for waist diameter, Krzysztof Kościński, a researcher at Adam Mickiewicz University, notes in a study on waist-to-hip ratio attractiveness in women that "a narrow waist is a visual cue of the absence of pregnancy and therefore current fecundity—a feature that ancestral men sought in women. This may be an especially important cue in humans because women do not signal their present fertility in any other easily perceptible way."
7. Waist-Hip Ratio.
Numerous studies have been done on the relationship of waist-to-hip ratio (WHR) and attractiveness in mate selection. In one oft-cited study done by Devendra Singh at The University of Texas at Austin, researchers determined that in "western societies, a narrow waist set against full hips has been a consistent feature for female attractiveness, whereas other bodily features, such as bustline, overall body weight, or physique, have been assigned various degrees of importance over the years."
Although researchers acknowledge the necessity of cross-cultural research, they add that "WHR represents an important bodily feature associated with physical attractiveness as well as with health and reproductive potential."