10 Fascinating Facts About Eyes
The eyes may be said to be the windows of the soul, but a look at our eyes also sheds some interesting light upon diverse facets of human biology. In this list, our discoveries take us through a surprising story about the history of the blue eye mutation, lesser-known facts about eye color and disease correlations, hidden blind spots, and why we can shed three different types of tears.
10 Blue-Eyed People Have A Common Ancestor
Blue-eyed humans make up a significant percentage of the population in certain areas of Europe, Eurasia, and the lands inhabited by the diaspora of these populations. Despite a range in distribution, scientists have determined that blue-eyed individuals can be traced back to a single common ancestor who would have resided in the Baltic Sea region 6,000–10,000 years ago.
Prior to a peculiar genetic change, all humans had brown eyes. A team led by Hans Eiberg from the University of Copenhagen discovered that blue-eyed humans were created by a genetic mutation on the OCA2 gene, which specifically cuts down melanin production in the iris. If the genetic effects went all the way, we would be seeing albinos rather than light-eyed individuals.
Eiberg was the original identifier of OCA2 as the gene responsible for eye color, continuing research begun in 1996. The study compared people from across Eurasia and determined just how specific were the roots of the wide-ranging mutation.
9 Men And Women Exhibit Differences In Visual Perception
Men and women appear to see differently, according to some rather interesting scientific investigations. According to research by Israel Abramov and his team from CUNY’s Brooklyn and Hunter Colleges, men are more sensitive to detail and motion, whereas women excel to a greater degree when it comes to picking up the nuances of color. The study included a comparison of male and female vision with a request to describe different colors as they were shown. Men were found to require a longer color wavelength and also exhibited reduced sensitivity to slight differences between shades.
However, male volunteers exceeded the capabilities of females when it came to rapidly moving images. Males could better identify rapidly shifting images composed of colored bars compared to the women, who experienced a greater challenge at this particular task. Abramov explained that these factors are linked to thalamic neurons within the primary visual cortex, which are influenced during development by the presence of androgens.
Research at the University of Bristol indicated another difference in male versus female visual activity patterns, this time in the area of how men and women use their eyes. Men tended to fix their gaze on an individual’s face or other point of focus, whereas women would tend to shift their gaze at different parts of an image when asked to look at still images.
8 Eye Color, Facial Morphology And Trust
Eye color appears to be linked to morphology and human perceptions of trustworthiness, according to a recent study in Europe. In January 2013, Karel Kleisner and her colleagues from Charles University in the Czech Republic published research identifying some fascinating biological and sociological relationships. When facial structure and eye color were compared, it was found that brown-eyed men typically possessed broader chins, larger mouths and noses, and closer eyebrows with increased prominence. In contrast, blue-eyed men had “finer” features, with narrower, more downturned mouths, longer chins, smaller eyes, and widely spaced eyebrows. The faces of these men were generally more angular in appearance.
Interestingly, public perceptions of trustworthiness from all audience members tested showed that these blue-eyed men with correspondingly different faces were less likely to garner trust from subjects. However, the few men with blue eyes who had less typical, broad faces garnered more trust. Women’s facial structures and eye colors did not seem to affect observer perception of trustworthiness, suggesting that human females may be judged according to different factors than the ones to which males are subject.
Leave a Reply