An example of anthropomorphism in public science discourse:
"There's a natural crevice between the gun and the teeth, and that's where the bacteria can sit, and they think 'Well, he'll never find me here'…
Night time your saliva flow stops, so if you have bacteria on the surfaces of your teeth and in-between, it means while you are sleeping, the bacteria and whatever you have eaten during the day have a little bit of a field day, and that's when they can be most prolific."
Dr Claire McCarthy (King's College London) was talking on an episode ('Can you be addicted to sugar?') of the BBC's 'Inside Health'
This is anthropomorphic because bacteria have no central nervous system and so do not think anything. While bacteria may have evolved to have behavioural traits which lead to them tending to be located in places that are less accessible, any suggestion that they deliberately choose good hiding places is a pseudo-explanation (something with the form of an explanation, but scientifically unsound). This is therefore only figurative language, which may nonetheless encourage people to carefully clean their gumline.
Read examples of anthropomorphism in science
That bacteria have a field day while we sleep is to employ an English idiom (which may be unfamiliar to some second language users).
Read about communicating science through idioms
