In other words, the variation in height from family to family right now is far larger than the variation in average height from century to century.
If you time-traveled to the 's, you would not notice that the people are shorter on average. Now, let's look at Europe. Unlike in the United States, the numbers reported in the book Height, Health, and History indicate that in European nations, the average male height has been changing more steadily. In the Netherlands, Denmark, Sweden, and Norway, the average male height upon conscription has steadily increased from about cm in to about cm today.
Similarly, in Italy and France, the average male height upon conscription has steadily increased from about cm in to about cm today. Thus, these European nations have gained about 13 cm in average height over the last years. To give you an idea of what this means, 13 cm is about the width of two tennis balls. As we can see, these European nations did indeed see a more significant gain in height over the last years—much larger than that seen in the U.
We could continue on and look at other countries, but I think we have looked at enough data now to allow us to summarize the main points:. Topics: evolution , height , taller. Although an individual's genetic code does significantly influence his adult height, a few hundred years is not long enough for overall genetic evolution to take place. Niger, one of the world's poorest and least developed nations, also has the world's highest total fertility, with women often bearing more than seven children.
Rather than natural selection, from a genetic viewpoint today's record heights speak to genes getting all they desire for maximally performing their developmental jobs.
It's not just genetics. All that being said, it's worth noting that high stature is as a sign of attractiveness across many cultures. Height also serves as a strikingly reliable gauge of earning potential. This tallness benefit does cut off though. Height clearly does not linearly correlate with wealth — athletes and famous fashion models aside. Multimillionaire CEOs are not all colossuses.
Komlos says the benefit tapers off in the vicinity of cm as people go from aesthetically tall to, well, eyebrow-raisingly tall.
Instead of a blessing, extreme height can be a curse. Lanky people have to stoop through doorways and struggle to fit in cars. Taller folks are more prone to certain maladies as well, such as joint and cardiovascular problems.
Robert Wadlow, officially the tallest man ever to have lived, is a prime example. A pituitary gland disorder made him soar to 2. He had to wear leg braces as he got older in order to walk; an infected blister from a poor-fitting brace contributed to Wadlow's death, age Robert Wadlow Credit: Getty Images. Given these considerations and the recent historical run of height gains, Komlos thinks humankind has probably reached its population-level pinnacle.
Leonard agrees. If we've indeed topped off terrestrially, what about extraterrestrially? Could people living in space or on other worlds somehow end up taller than conventional Earthlings? This notion of non-Earthly lifestyles altering human forms frequently pops up in science fiction.
Compare the growth process to a wind-up toy train, Baron says. Upon release, the train zooms forward but gradually slows and putters out as the spring winds down. When we use up our genetically programmed growth potential, like the unwinding spring in the toy train, our growth slackens and eventually stops. Hundreds of genes likely influence height. In fact, a study out in found over height-related genes. These genes manipulate the behavior of growth plates and control bone length.
Though rare, mutations in height-related genes can trigger unusually tall stature. There are other conditions that affect height, too, such as skeletal dysplasias, which result in shortened and often malformed bones. Mailund suggests we may evolve in ways that help us to deal with this.
We might just change that. It sounds more like science fiction. But we can do that right now. Perhaps in the future, implants will be used simply to improve a person. As well as brain implants, we might have more visible parts of technology as an element of our appearance, such an artificial eye with a camera that can read different frequencies of colour and visuals.
But in the future, Mailund suggests, it may be seen as unethical not to change certain genes. This is all rather hypothetical, but can demographic trends give us any sense of what we may look like in the future? Predicting out a million years is pure speculation, but predicting into the more immediate future is certainly possible using bioinformatics
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