Why Are Pigs Pink?
Pigs are pink because early humans bred them to be pink. Only domesticated pigs are pink in color. In the wild pigs are black or usually brown. Starting at around 10,000 years ago humans selectively bred only the most colorful pigs to artificially create the colorful variations you see today.
When I was just 10 years old I went to work on a small homestead that my uncle owned. When she was growing up, my mother thought it would be a good idea for me to learn what her life was like. My uncle had just 2 pigs and a few chickens so it wasn't exactly like what I had pictured in my imagination when she told me I would be spending my Summer on a farm.
It was, however, hard work for a 10-year-old. Getting up and early to feed the animals and cleaning up the poop and all of the other small jobs that come along with a farm.
Remembering my time on the farm got me thinking. Why are cartoon versions of pigs always portrayed as being pink? When you see films like "Babe" or shows like "Peppa the Pig" aren't they always pink? The pigs I worked with all the years ago were black and brown. Where do pink pigs come from?
Pigs Come In Many Different Colors
When you see domesticated pigs on a commercial farm they may look pink but this is not the color of their fur. Most of these pigs are actually white, but because they have been bred to have very little fur compared to wild hogs, their skin shows through this thin layer of white fur.
Pink pigs are what occurs when pigs stop producing melanin. Melanin is a dark brown to the black pigment that occurs in the skin of wild pigs. When pigs stop producing this they default back to the natural color of skin which is pink.
Wild hogs, on the other hand, are almost always black or brown.
Why the different colors?
The reason for the different color in pigs are all thanks to human intervention and domestication of wild pigs. Scientists have estimated that humans started domesticating pigs at around 10,000 years ago. At first, the wild pigs were all either black or brown.
The wild hogs naturally evolved to be these darker colors to help them be better hunters. Being dark-colored helped to camouflage them from both their prey while hunting. Their camouflage would also safeguard them from their own natural predators especially large cats like lions or tiger, who would have loved to eat them for dinner.
Because early humans selectively bred them to be pink, Pink pigs are this color. Why? No one knows for sure, but some scientists theorize that these early farmers did this for the pure novelty of having brightly colored animals they could then show off to the rest of the tribe.
How did they get them to be pink? Exactly how did they change the colors? Well, we know that it didn't happen overnight. These early farmers would cherrypick the pinkest pigs then mate them with each other in the hopes of producing offspring that would inherit the colorations of the parents. When done over the course of generations, these pigs would become highly distinguishable from their untamed cousins.
Are there any wild pigs that are pink?
In wild populations, pink pigs would quickly be eradicated from the population.
Black and brown pigs would have a great advantage over pink pigs in the wild.
Suppose that both a pink pig and a black pig were hunting for food. The camouflage effect of having black would give the black pig a greater chance of a successful hunt. Because it would be detected by the prey earlier because of its coloration, while the pink pig would probably fail. The pink pig would not be able to hide.
Furthermore, pink pigs would be much more easily hunted by predators.
This all leads to pink pigs in the wild dying out. They would not be successful enough to pass their genes on to another generation.
Natural selection or survival of the fittest would eliminate pink colors in pigs pretty rapidly.