2.1.2 Sampling, sorting and preservation protocol
Dung beetle sampling was conducted using baited pitfall traps and baited
funnel pitfall traps with human dung as the bait because it is widely
accepted to be the best bait to attract dung beetles (Howden & Nealis,
1975; Kudavidanage et al., 2012; Larsen & Forsyth, 2005). Exact details
of trap materials and construction are appended (Appendix, Figure S1).
Traps were retrieved after 24 to 48 hours, and captured beetles were
brought back to the laboratory for morphological identification and
sorting using an Olympus SZX10 microscope.
Onthophagus . babirussa were separated from other species
via their distinct thorax patterning. Specifically, the lateral portions
on both sides of the thorax are in a lighter shade of brown compared to
rest of thorax and contain one or two darker brown spots (Appendix,
Figure S2 & S3). Mid femurs of all individuals were dissected for
molecular work (see below) and male O . babirussaindividuals were separated from females based on the presence of head
horns. Male individuals were kept in separate, labelled Eppendorf tubes
with a drop of 1x Phosphate-Buffered solution (PBS).