Anyone who watches a dog in the park will notice that sometimes the puppy sticks its nose into the air, and sometimes it sniffs the ground excitedly. Until now, scientists could not understand why animals prefer to sniff the air rather than the ground. An international team of researchers is shedding new light on this topic.
“We used what we know about how scent is transported by wind and land to better understand why animals behave the way they do,” said study co-author Nicola Rigoli. “Then we used machine learning techniques to determine the optimal strategy for finding the source of the odor.”
The researchers created computer simulations to determine how odors move in turbulent conditions. They then modeled the advantages and disadvantages of sniffing the air versus sniffing the ground. The experts created a computer simulation of the animal designed to minimize tracking time. They noticed that, like real animals, it often walked back and forth, sometimes sniffing the air, and sometimes the ground.
The researchers found that when an animal is upwind from a scent source, it will often stick its nose out to catch the scent. As they approach the source, they begin to sniff the air less and more the earth.
“Smells in the air are rarer and more difficult to track than smells on the ground, but they spread faster and over long distances. Therefore, the benefits of sniffing near the ground or in the air depend on the distance of the animal from the source of the smell,” said study co-author Gautam Reddy.
The researchers noted that the findings may be relevant for marine life, including crabs and shellfish. Although the results obtained may not be applicable in real situations, the authors of the study hope that further research will yield more practical results.
“We hope our results will inspire other scientists to conduct experiments with dogs, rodents and aquatic animals that will help us learn more about these behaviors in real-life settings,” said Massimo Vergassola, senior author of the study.
The study was published in the journal eLife.