Unraveling the Mysteries of Our Sense of SmellOur sense of smell is extremely complicated, but we rarely think about it. That is, until it's no longer available to us. COVID-19 did a job on many victims' sense of smell, sometime temporarily, sometimes permanently. Those who never caught the disease smelled fewer things, too, as we stayed home from work and wore masks in public. We don't realize how much flavor is based on smell instead of taste, and how much we rely on smell to warn us of noxious conditions, such as smoke from a fire. While our vision relies on just three types of receptors, the human body has 400 or so different kinds of olfactory receptors. Often many receptor types work together to identify a certain smell. Not all of those receptors work in every person. Some people are sensitive to the distinctive smell of urine after eating asparagus, while others cannot detect any difference. And people either pick up or interpret some smells differently, like how cilantro is a lemony herb to some people while it smells like soap to others. And even though a normal human sense of smell is much less sensitive than, say, a dog's sense of smell, we still know relatively little about it. New research is ongoing about the genes that affect how our olfactory receptors work and don't work. Other questions include why we, as a species, have inactive genes for smells that were important to our evolutionary ancestors. Read about the new research into our sense of smell at Smithsonian.(Image credit: Neeta Lind) #smell #odor #sense #olfactory
Ancient Egyptian Tomb Smells of Fish, Fruit and Beeswax BalmElectric fridges ain’t got nothing on Egyptian preservation technique.An assortment of delicacies kept inside an ancient Egyptian tomb dated 3,400 years ago was found to still be smelling fragrant when it was unearthed. The jars containing the food were left inside the tomb to nourish its inhabitants, spouses Kha — an Egyptian ‘chief of works’, or an architect — and Merit, his wife. According to experts, the unidentified ancient food still bears hints of fruity aroma, which they are going to analyze to determine conclusively.The 1906 discovery of the tomb in the Deir el-Medina necropolis near Luxor remains the most complete non-royal ancient burial ever found in Egypt, revealing important information about how high-ranking individuals were treated posthumously. Image: J. La Nasa et al./J. Archaeol. Sci#EgyptianTomb #Luxor #burial #smell #fish #fruit #beeswax
Training Ants to Sniff Out CancerWe were all pretty astonished to learn that dogs, with their advanced senses smell, can detect cancer and other illnesses in people even before diagnostic tools are able to. It turns out that dogs aren't the only animal with such a sensitive sense of smell (like rats who can find land mines), and there are other creatures that are more easily trained to do it. Like ants. Ants are very sensitive to some volatile organic compounds (VOCs) that enable them to find food, avoid enemies, and reproduce. It's not such a stretch to think they could recognize the organic compounds that make up cancer cells. But would they? We think of ants as unthinking soldiers, doing their designated jobs for the group without variance or sense of self-preservation. However, a recent experiment showed that ants of the Formica fusca species can be trained to distinguish breast cancer cells from non-cancerous cells. And quickly!An experiment with ants showed that they can learn this skill in about 30 minutes, and master it in three days. A dog can learn it, too, but it takes months, up to a year of training, and dogs are more expensive to maintain.Okay, how long is it until we replace mammograms with a picnic with ants? It will take time. Training ants is easy compared to cataloging the VOCs of various cancers, and that's a human task. Read more about this finding and how ants might be out future diagnosticians at New Atlas. -via Damn Interesting (Image credit: Syrio) #cancerdetection #smell #ant