Researchers have claimed that households that have dogs residing in them have more types of bacteria - including those that are rarely found in the homes where dogs don't reside.
Dr. Rob Dunn, an associate professor of biology at North Carolina State University and co-author of a paper, said that the team wanted to know which variables influenced the microbial ecosystems in their homes, and the biggest difference that they have found so far is whether they own a dog or not.
He said that the team could tell whether a person owns a dog based on the bacteria that they will find on their TV screen or pillow case, giving an example, he said that there are bacteria normally found in soil that are 700 times more common in dog-owning households than in those without dogs.
Citizen scientists in 40 homes took samples from nine common surfaces to help researchers determine what kinds of bacteria lived there, and in what relative numbers.
The nine surfaces were wiped with sterile swabs from which researchers collected DNA to see which organisms were present.
The nine surfaces were the TV screen, kitchen counter, refrigerator, toilet seat, cutting board, pillow case, exterior door handle, the trim around an interior door and the trim around an exterior door.
The study from North Carolina State University and the University of Colorado found 7,726 phylotypes, or kinds, of bacteria in the homes.