An investigation has shed light on the hundreds of organisms that live inside the human umbilicus.
The navel is a great source of bacteria. And it is that this zone harbors, at least, 60 species of fungi, bacteria and yeasts, according to the data obtained in 2012.
Thus, it could be said that the differences between individuals are large , as stated by Professor Robert Dunn, of the State University of North Carolina (United States).
Dunn and his colleagues have so far collected skin bacteria from the navels of 391 subjects.
In the study, men and different ages, ethnic origins and even different hygiene habits were included .
Researchers have not only focused on the content of bacteria in the samples, but have also discovered fungi and some interesting yeasts.
Scientists have confirmed the viability of these organisms through culture and are now in the process of sequencing the DNA of each species.
Preliminary results indicate that the number of organisms per person varies considerably .
Until now, no clear explanation of why people differ so much in terms of their bacterial communities was known.
The differences that resulted from this study do not easily coincide with gender, ethnicity, age; not even with the frequency of washing. It is something more.
The researchers, however, came to the conclusion that most of us share a relatively small group of bacterial species, with hundreds of other rare species having both.
According to Dunn, it may be that most of us share our common species, while the rare species we encounter are a measure of our individual histories and are inherently unpredictable.
These bacteria are a defense
It is likely that many people now begin to be more aware of the importance of navel washing.
However, Dunn asserts that such organisms, which are also found in our forearms, hands and, really, on the entire surface of the body, have an important function.
It is a kind of first line of defense against the pathogens that settle on us.
A kind of army that lives in our skin and that, when it meets a newly arrived pathogen, has the first response to fight against it.
A human being who has successfully erased all microbes from their body could be at a high risk of suffering a deadly skin infection.
They change our behavior
They point out that the bacteria can even change the behavior of their carriers .
Steroids and other natural chemicals found under the armpits are an example.
These compounds are the main products of bacterial metabolism and can lead to all kinds of odors that affect the way we interact with others .
For example, some Corynebacterium metabolize testosterone to produce a musk, a smell similar to urine, while others metabolize sebum and sweat to produce an odor like onion.
According to these researchers, there is evidence that bacteria produce a strong odor and that underarm odors serve as signals of recognition among humans .
These signals, in turn, seem to help us distinguish between individuals. Mothers, for example, have no problem recognizing their children just by smelling their armpits.
Even with such family ties, our most intimate relationships in life are the still mysterious tiny organisms.