[Opinion] Evolution and the Genetic Instinct for Reproduction

Carbohydrates are sweet, while fats are savory. Proteins are full of “flavor.” Salty sodium is vital to a healthy metabolism. Biologists explain that living creatures have evolved to adhere to various tastes for survival. Likewise, the instinct for survival has educated human beings to avoid getting hurt or burned.

A species that fails to encrypt this instinct into its DNA becomes extinct. Once inscribed, however, the encoded bio-pattern forces the creature to act on the encryption, even when that pattern causes harm. The DNA data of a bird directs the bird to feed any small creature that cries in its nest. This encryption sometimes veers off into a wrong direction. For example, a skylark sometimes kills its own babies to feed a cuckoo baby that was put in its nest.

The human race is not free from such evolutionary error. Suffering from lack of food for more than six million years, human beings have taken it granted to store up whatever nutritional substances in their systems whenever an opportunity allows. Those sitting on the top of the past social strata got obese. In the contemporary world, obesity still haunts human beings. Evolutionary biologists point to the absence of the genes that could possibly prevent the hyper-consumption. They believe the speed of biological evolution failed to catch up with the pace of mankind’s changes in lifestyle.

Evolutionary mistakes are not erroneous all the time, however. Sexual desire stems from the evolutionary purpose of reproduction. Still, human beings jump at the opportunity without any such intent. Our DNA encryption necessitates the love for babies. It pushes us to adopt babies without any genetic connection as well. Recently, Korean entertainer Heo Su-gyeong confessed that she had got pregnant with the help of a sperm bank. Legal and ethical issues still hover over the matter. Putting things into the evolutionary perspective, she acted more “genetically.” Adoption is a more alien idea in terms of the instinct. The economic independence of women has also made it possible.

Heo Seung-ho, Editorial Writer, tigera@donga.com