There is some unintentional hilarity in the latest example of the "humans are still evolving" story that periodically appears (in slightly different forms) on science news sites. The second photo in the article shows some hands holding small potatoes. The article is trying to claim that people living near the Andes mountains have evolved a better ability to digest small potatoes. The writer probably forgot that in English the phrase "small potatoes" is a figure of speech or expression meaning "something insignificant, of little importance." So the small potatoes visual symbolizes the examples discussed in the article, all of which are examples of unimpressive "small potatoes" microevolution.
The first example given of current human evolution is the "small potatoes" example of lactose tolerance. Humans have been breeding cows for their dairy products for something like 10,000 years. It is claimed that about 10,000 years ago, only children could drink cows' milk, and that adults were unable to digest cows' milk. Supposedly there was a genetic variant allowing adults to digest cows' milk, and that such a variation became more common during over the past 10,000 years, allowing more and more adults to digest cows' milk. The evidence for this claim is rather weak, and even if it is true, the claimed example of evolution is only a not-very-impressive example of microevolution.
The second example given of current human evolution is another "small potatoes" example of a small change in digestion: the claim that "Quechua people of highland Indigenous Andean ancestry" are better at digesting small potatoes. The third example is the "small potatoes" example that some people living at high altitudes in Tibet have red blood cells with "unusually high oxygen saturation." This is a very minor bodily difference.
We then have an example of how evolutionary narratives are adapted to fit any facts, in a "heads I win, tails you lose" manner. First the article suggests that darker skin evolved in Africa to protect from sun damage. Then the article suggests that lighter skin was favored in Europe, so that people could get more vitamin D from sunlight. There is no very strong evidence behind these claims, which in any case involve something only superficial (skin color).
The final example of current human evolution cited by the article is a laughable one: an increase in nearsightedness.
We read this:
"Myopia, or nearsightedness, has surged in the past few decades. In 2021, researchers found evidence in the UK Biobank that the condition is associated with mutant alleles.
These alleles have increased in frequency over the past 25 years, possibly because of natural selection. While nearsightedness might be a disadvantage for survival, some of the gene variants linked to this trait may have other advantages for reproduction."
Notice the "heads I win, tails you lose" type of affair going on. If nearsightedness is decreasing, and vision in a population is getting better, that will be cited as evidence of the amazing power of evolution to produce benefits in organisms. But if instead nearsightedness is increasing, and vision in a population is getting worse, that is also cited as evidence for the amazing power of evolution, with a "may have" thrown in.
Let's get real here. Microevolution refers to minor examples of evolution. The word macroevolution refers to very big and very major examples of evolution, such as an evolution from microscopic organisms to large visible organisms, or an evolution from sea-dwelling organisms to land-dwelling organisms, or an evolution from non-flying organisms to flying organisms, or an evolution from ape-like creatures to humans.
We know of a few minor examples of microevolution occurring in humans, such as the ability of more humans to digest lactose, and the ability of some humans to breathe better at high altitudes. But no one has ever observed macroevolution in the human population or any other population of organisms. Macroevolution is the alleged appearance of major complex visible biological innovations in organisms due to natural evolutionary processes. For example, if a species that did not have wings once evolved into a species that did have wings, that would be an example of macroevolution. And if a species that did not have eyes ever evolved into a species that did have eyes, that would be an example of macroevolution.
Recorded history provides no example of macroevolution occurring in the human population or any other population of organisms. We have Egyptian statues and bas-reliefs of humans dating from 5000 years ago, and the humans depicted look just like the humans of today. We have priceless ancient literary works such as those of Plato, proving that humans were capable of brilliant thought and writing thousands of years ago. If humans from five thousand years ago were transported to the current age and dressed in modern clothes, they could pass for modern humans.
Evolutionary biologists claim there was in the past some huge amount of macroevolution that caused ape-like ancestors to transform into humans capable of speech, writing and city building. But a study of the growth of human population will cast doubt on such claims.
The number of humans that have lived has been estimated at 100 billion. But a web site discussing this issue tells us that 99% of these people have lived in the past 10,000 years. Since 8000 BC some 100 billion humans have lived, but in the period between about 400,000 BC and 8000 BC, the total number of humans or pre-humans who lived was quite probably no greater than about a billion, and very probably less than 3 billion (the average population size being only about 20,000 or smaller for most of this time). A web site discussing the issue states at 8000 B.C. the total number of humans who had ever lived was only about a billion.
But we know there has been no macroevolution of humans since 8000 BC -- only a little microevolution like better lactose digestion and better high-altitude breathing in some people. A statue from about 9000 BC shows a human with the modern human form, as do skulls and skeletons from around such a time. We also know from archeological records that humans were building towns around such a time, in places such as Jericho. We also know from cave paintings that something like modern humans existed around 30,000 B.C.
So if you believe the conventional account, you must believe that a totality of no more than 3 billion humans or pre-humans living before 8000 B.C. underwent enormous macroevolution (resulting in humans that had language, abstract thinking and symbolic abilities), but that in 100 billion humans living since 8000 BC there has been no such macroevolution. Such an idea is not credible. Why would there be such dramatic macroevolution during less than 3 billion lives, and no macroevolution during the subsequent period in which there were 100 billion human lives? We would think the opposite would be more likely.
A science site says, "An effective population size of 10,000 has been estimated for the most recent common ancestor of modern humans and of Neandertals (Ptak et al., cited in Premo and Hublin, 2009)." Conversely, our planet has had billions of humans for about 70 years. According to the account of our evolutionary biologists, from a population of only about 10,000 or a few tens of thousands of organisms before 50,000 B.C. there came some dramatic burst of macroevolution transforming ape-men into humans, but no such macroevolution has come from any of a population of billions of humans living in modern times.
When discussing the unlikelihood of getting dramatic macroevolution from a small population, and the relation of population size to the likelihood of there appearing large complex evolutionary innovations, our biologists try their best to cloud the waters by distracting us with side points. But the matter will be more clear to anyone who considers a hypothetical example. Requiring almost infinitely improbable protein molecule innovations and so much more, the appearance of a macroevolution innovation largely by random mutations can be compared to some typing monkey accidentally producing a brilliant essay or a clever computer program. Now imagine if some huge group of scientists tested for years billions of monkeys trained to sit at keyboards and type, and saw no such worthy outputs ever appearing from their efforts. It would then be very dubious for such scientists to claim that such worthy outputs came in the past from a group of only about 15,000 such typing monkeys. It is just as dubious to claim that some tiny population of perhaps 15,000 pre-humans yielded some gigantic marvel of macroevolution resulting in speaking and writing humans, when no macroevolution at all has come from population sizes 300,000 times larger.
The diagram below illustrates the difficulty. Each brick in the diagram represents very roughly a million human or pre-human lives, taking place after 200,000 B.C. According to the Darwinian account, there was some huge evolution leap at the very top of this pyramid, in the time before 10,000 B.C., when there was only a total of a few million human lives or pre-human lives -- some giant leap transforming pre-humans into humans capable of building cities, talking, and writing books. But we know that there has been no major evolution in humans since 8000 B.C. What sense does it make to think that Darwinian evolution would yield so great a leap in human abilities at the tiny top of such a pyramid, when there has been no such leap in the part of the pyramid constituting 99% of its weight?
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