White-nosed Bats
https://phys.org/news/2018-11-cryptic-disease-transmission-epidemics.html
https://www.whitenosesyndrome.org/static-page/what-is-white-nose-syndrome
Over the past several years, the North American bat population has been devastated by white-nose syndrome, caused by fungal infection. High infection rates among bats of the same species is to be expected, due to their proximity when hibernating over the winter. However, one species of bats which has the tendency to hibernate alone also has high infection rates. A recent study (detailed in the first link) among bats has found an explanation for this unexpected infectivity. By marking bats with different colors of fluorescent dust, researchers managed to map the network of connections that bats had with members of the same or different species during their brief periods of activity. Their network explained the transmission rate of white-nose syndrome better than hibernation social groups could.
Why is this bat study so important? Disease transmission and epidemics have always been a huge concern, and organizations such as the WHO and CDC constantly seek to mitigate the effects of or even prevent transmission of infectious or dangerous diseases. Encounters between infected and healthy individuals contribute to the spread of disease. Although bats in this study did not often directly encounter bats of another species, they succeeded in transmitting the fungus to those other species through brief encounters or even just by sharing the same airspace and travel routes. It is important to remember that chance encounters and even proximity contact are often enough to form a connection among nodes in a network, creating a new edge for disease to spread and infect more individuals than it originally could. If chance encounters with strangers is all it takes to form these new edges, tactics such as quarantining infected individuals is all the more effective at curbing the creation of these disease network edges.