Breasts come in many different shapes and sizes, but one thing is special that only humans have large breasts.
There are more than 5,000 species of mammals living on this planet. However, only humans are the only species with large breasts, which persist throughout life, according to IFLScience.
The question arises: Why are human breasts so big, is it an evolutionary error?
Every other mammal develops breasts only temporarily during ovulation or lactation. Basically, the purpose of breasts in animals is to make milk and to breastfeed. So once the milk is gone, the animal’s udder also disappears.
But in humans, it’s different, breasts form during puberty, not during pregnancy , according to IFLScience.
Only humans have large breasts.
In 1987, biologist Tim Caro explored seven theories on the subject. In it, he argues that human breasts allow the infant to suckle from the side, giving the mother more flexibility to do many other tasks.
But his theory still doesn’t explain why after breastfeeding, a woman’s breasts persist.
Perhaps the most popular idea was first proposed by Charles Darwin and later discovered by zoologist Desmond Morris in a book called “The Naked Ape” , published in 1967.
In it, Morris theorizes that breasts develop as a substitute for the enlarged buttocks of other female primates during ovulation, according to IFLScience.
According to this hypothesis, as soon as primitive humans began to walk upright, it was no longer easy for men to tell when a woman had reached puberty and breasts may have formed as an answer to the question. this question.
This theory would at least explain why women’s breasts develop during puberty, but it still doesn’t explain why human breasts persist after menopause.
Let’s take a closer look at the person’s breasts. The biggest difference is that they contain more fat than other mammals. Fat fills the breast tissue, giving it its shape as it does with milk, but persists without disappearing as it does in other animals, according to IFLScience.
Human breasts can be too large, which in turn can cause back pain and chest tightness. This is why many women reduce their breasts. In the US alone, more than 61,000 people had breast reduction in 2016.
But breasts are not only uncomfortable for some, it can also cause death for a woman. Breast cancer is the number one cause of death for women worldwide. It affects about 1.5 million women each year and killed 570,000 in 2015, according to IFLScience.
However, according to scientists, breast cancer is not common among other primates. This may be because cancer risk increases with age, and other primates do not live long enough to develop breast cancer. Or perhaps it could involve permanent breast tissue that is unique to humans.
Cancer occurs more commonly in rapidly dividing tissues. Breast tissue divides at a rapid rate, so there is a greater risk of cancer occurring. That may explain why removing both breasts reduces the risk of breast cancer in women by 95%.