In history, there have been 9 species of humans and will we evolve into a new species?

There used to be nine species of humans, now there are just us. But how did the new species evolve? For that to happen, isolated populations would need to be subjected to distinct selective pressures.

Humans will grow taller and taller.

Animals often evolve to become larger over time. It's a trend seen in tyrannosaurus rex, whales, horses, and primates—including apes.

Early hominins such as Australopithecus afarensis and Homo habilis were small, measuring between 120 and 150cm tall. Later hominins such as Homo erectus, Neanderthals, Homo sapiens, etc. were taller. Humans have continued to grow taller throughout history, partly due to improved nutrition, but genes also appear to be evolving.

Why humans have become so tall is not clear. In part, low mortality rates may have driven the evolution of size; growth takes time, so living longer means more time to grow. But women also prefer taller men. So both mortality and a preference for physical attractiveness would likely have driven humans to evolve toward greater height. Today, the tallest people in the world are in Europe, led by the Netherlands, where men average 183cm and women 170cm. One day, most people could be that tall or taller.

As we grew taller, we became more agile, which may seem paradoxical. Over the past 2 million years, our skeletons have become lighter as we rely less on strength and more on tools and weapons. As agriculture forced us to settle down, life became more sedentary, and our bones lost strength. As we spend more time at desks with keyboards and steering wheels, these trends are likely to continue.

Humans have also lost muscle mass compared to other primates, especially in the upper body. That will probably continue. Our ancestors hunted antelopes and dug up roots, then plowed and reaped the fields. Today, jobs increasingly require us to touch, to use words and codes. That forces us to use our minds rather than our muscles. Even manual laborers like farmers, fishermen, and craftsmen have machines like tractors, forklifts, and engines to help. As physical strength becomes less necessary, human muscles will continue to atrophy.

Our jaws and teeth will also shrink. Early hominins ate plants and had very large molars and lower jaws to grind up fibrous vegetables. As humans transitioned to a meat-based diet and then started cooking their food, our jaws and teeth gradually shrank. Modern processed foods like fried chicken, chips, and cookies make us chew even less, so our jaws will continue to shrink, and in our evolutionary future, we may no longer have wisdom teeth.

Will people in the future be more beautiful than they are now?

After humans left Africa 100,000 years ago, remote human tribes were isolated by deserts, oceans, mountains, glaciers, and distances that were then endless. In many parts of the world, different selective pressures such as climate, lifestyle, and beauty standards… caused human appearance to evolve in different ways. Ancient tribes developed distinct skin, eye, hair, and facial features.

With the rise of civilization and new technologies, these populations were connected again. Wars of conquest, empire building, colonization and trade, including human trafficking, changed and intermingled all populations. Today, roads, railways and air travel also link people closer together. The ancient aborigines could only walk a few dozen kilometers to find another tribe, now we can fly thousands of kilometers in a few hours. We are increasingly becoming citizens of the world, moving freely in a flat world. This will lead to the creation of a world of mixed-race people of African-Eurasian-Asian-Australian-American descent from all five continents with light brown skin, dark hair, and skin color. It is believed that the facial features of the next generation will tend to be closer to global neutrality.

Sexual selection will further accelerate the evolution of human appearance. With most forms of natural selection no longer in play, mate choice will play a larger role. People may become more attractive, but more uniform in appearance. Globalized media may also create more uniform standards of beauty, pushing all humans toward a single idea of ​​beauty. However, gender differences may be exaggerated if the ideal human is set as masculine-looking men and feminine-looking women.

Do new species appear?

Human evolutionary tree.

There used to be nine species of homo, now there is just us. But can humans still evolve? For that to happen, isolated populations need to be subjected to distinct selective pressures. Distance no longer creates isolation, but in theory, reproductive isolation can be achieved through selective mating. If people are separated culturally, for example by marriage based on religion, class, caste or even politics… then distinct populations, even species, can evolve.

In The Time Machine , science fiction novelist H.G. Wells saw a future where classes created separate species. The upper class evolved into the beautiful but useless Eloi and the working class became the ugly, short Morlocks.

In the past, religion and lifestyle sometimes created genetically distinct groups, such as Jews and Gypsies. Today, politics also divides people, so could it divide us genetically? Liberals now gravitate toward other liberals and conservatives toward conservatives; many people on the left won't date people on the right, and vice versa.

Could this split humans into different species? Probably not. However, to the extent that culture divides humans, it could drive evolution in different ways, in different people. If cultures become more diverse, this could maintain and enhance human genetic diversity.