Social Skin Microbiome
microbiology | social intelligence | human physiology
Storytelling through the human body
Storytelling through the human body
roles: wet lab researcher | microbiology analyst | lab experimenter
What can our hand’s microbiome reveal about our social behaviours?
Analyzing bacterial colonies on the palm of three people’s hands with different social experiences.
The 100 trillion microbes living in and on people — that’s ten single-cell organisms for every one human cell — are a fundamental component of human physiology. In a very real sense, the human microbiome is as much a functioning organ as are the intestines into which so many of them are packed. But their influence goes way beyond the digestive tract, into such sites as the skin, eyes, urogenital tract, nose, and lungs.
— Erin Odya
Background
A microbiome includes the microorganisms (flora and fauna) that live within regions and on the surface of the human body. Previous research shows a reciprocal connection between an animal’s social behaviour patterns and its microbiome. With potential implications for the animal host’s fitness and emitted chemical signals in the nervous system responsible for social communication. Studied at scale, animals may be tracked for their evolution trajectory with microbial transmission strategies relevant to their social behaviour across ecosystems (Archie & Tung, 2015). I was curious, what could our own hand’s microbiome reveal about our social behaviours?
So I set out this experiment to isolate and analyze bacteria colonies derived from the palms of the human hand. The surface of the palms of the hands were ideal to analyze because the hand touches several surfaces on a daily basis. The expected results were that there would be an increased amount of bacteria found flourishing when inoculated on the agar plates, as opposed to the other areas of the body subject to sampling. Due to the increased number of surfaces the human hand comes in contact with, this area is anticipated to host a large bacterial community. I explored the social context in addition to the microbiome physiology of three students, including myself, as part of a biology lab centred on organism diversity.
Before the hand swab, the students followed lab protocol to wear their lab coats and wash their hands before proceeding to do a lab test. Their behaviour was observed while doing the test. Skin swabs were then collected from three students (pictured on an agar plate after incubation). During the lab test, Student 2 had visible nervous habits like biting their finger nails, fidgeting with a pencil, and touching their face. Student 1 did not exhibit these visually anxious habits. These activities may have reflected in the larger and smaller amount of colonies found on the palm of their hands respectively. When further asked about test anxiety, Student 2 ranked highest and Student 1 ranked lowest on a self-report measure. Note that these findings are simply exploratory and need further investigation to prove validity for any meaningful takeaway.
Description of Colonies from the Swab Plates
Photographs of 9 Unknowns selected for testing
Group Results and Summary from Diagnostic Media
Images of Diagnostic Plates
Gram Positive Strain Categorization
Also, if you’re not convinced by how powerful our human microbiome is to our cognitive life, check out its “second genome“ potential as termed by physiologist, Erin Odya:
“Researchers studying this cloud of microbes have called them the ‘second genome.’ A person’s microbiome starts to grow at birth — in fact, it may gain a toehold even before a person is born — and ultimately develops into a collection of on-board ecological systems somewhat akin to coral, with distinct colonies living in symbiosis. Even though bacteria are one-tenth to one-hundredth the size of a human cell, every person carries around up to five pounds of them. In other words, the microbes a person hosts weigh more than the three-pound brain does.”
What about the gut microbiome?
Outside of skin, I was curious how diet could influence a person’s gut microbiome! In this upcoming experiment, I explored the antimicrobial properties of different ingredients, like spices, used across social cultures on a common bacteria found in human intestines, like E.Coli.
Lab Poster
Life Sciences Semester Lab Presentation Poster
References
Archie, E. A., & Tung, J. (2015). Social behavior and the microbiome. Current Opinion in Behavioral Sciences, 6, 28–34. https://doi.org/10.1016/j.cobeha.2015.07.008