Cultural changes are likely affecting modern human evolution in ways we don’t yet understand. For example, research has shown that women rely on scent when choosing mates. But these days, we use all sorts of products to mask our scents.
In addition, hormonal birth control can change the way women react to the scent of potential mates. One study found that hormonal birth control caused women to be more attracted to men who were genetically similar to them, while women not on hormonal birth control were more likely to be attracted to men who were genetically different.
There is no way of knowing the long-term effects of modern cultural practices and technologies on human evolution. But scientists can make some educated guesses.
For example, it’s possible, says [evolutionary biologist Scott] Solomon, that the increasing use of in vitro fertilization could lead to more infertility. When infertility has a genetic cause, in vitro fertilization preserves in the population a gene that without the technology would have been weeded out by natural selection.
Modern technology may also be helping us evolve different bodies. Caesarian sections make the healthy birth of babies too large to make it through the birth canal possible. Increased use of these procedures could possibly lead to an increase in the average size of humans. A 2016 study models how that might already be happening in some populations.















