I took a cue from one of my readers who wanted a story about a rat. Perhaps later a story, for now, this: a random collection of things I find interesting about rats.
Commensalism is a relationship between two species where one of the species benefits and the other species is not affected. Rats often live with or near humans. They are not parasites. They are commensals.
Endemism is “the ecological state of a species being unique to a defined geographic location, such as an island, nation, country or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere.” Many species of rats are island endemics.
Zoonosis is the transmission of infectious disease from (usually vertebrate) animals to humans. In direct zoonosis the transmission is direct through air, bites or saliva. Zoonosis can also occur through a vector or an intermediate species that remains unaffected. Modern studies suggest that the Black Death, the pandemic that killed between 30-60% of Europe’s population in the 1300’s, was introduced into Europe by fleas that fed on the black rat passengers of merchant ships sailing from Asia into Europe. Rats live only about one year. In the late 19th century, specially bred pet rats came into vogue in Europe.
Metacognition is “the awareness or understanding of one’s own thought processes.” After rats became laboratory rats, scientists started to wonder whether rats have metacognition. The jury’s out on that one. At the very least, we could say that rats seem to have a psychology similar to humans. Snakes eat rats.
Rats have ben trained to detect land mines and tuberculosis through smell. Rats feature prominently in the “bamboo death” in northeastern India through the stuff that make up nightmares, the so-called rat flood. Rats have the ability to swim up sewer pipes and into toilets. I have at least a few phobias: trytophobia, claustrophobia and musophobia (fear of rats or mice). The musophobia I can trace back to one of my earliest memories. My mother screaming when a rat climbed up a sewer pipe and into our toilet in Bogota, Colombia in 1981. I was two. For years afterward, I would double and even triple check the toilet before using it. I’m not sure where the claustrophobia came from. Perhaps, the metacognition. [I do a whole post on trytophobia.]
The pied piper of Hamelin led rats away from an infested town and then the children, in punishment of the fickle nature of humans.