Sampling and experimental design
Arthropods were collected monthly from 20 households between August 2018
and October 2019 by citizen scientists in the West Midlands, UK (Fig.
1). Nine households were in sub-urban and 11 were in urban settings; the
active collection was done using a spider catcher (Brainstorm, Gisburn,
UK), and a pooter bug catcher (Ocean, Southampton, UK) (Fig. 1).
Immediately after collection, the arthropods were stored at -20℃ in
domestic freezers until monthly collection by the laboratory staff at
Aston University (UK), where samples were taxonomically identified at
the family level against entomological references (Chinery 1993; Chinery
& Falk 2007) using a stereo microscope (Motic Hong Kong Limited, Hong
Kong, China).