2.2 | Behavioral and morphological character scoring
By combining a semi-exhaustive literature review with exemplar cross-checking, we then scored two behavioral characters and 55 morphological characters (see Appendix B for character information, Wilson et al., 2022a for character matrix, dataset references and exemplar information) for all 110 genera in the supertree. Behavioral characters relate to retreat construction method and retreat-entrance type and are defined below. To score these characters we made extensive use of Coyle (1986), which remains the most thorough review of mygalomorph burrowing behavior to date, and then cross-checked this with taxon-specific literature (Wilson et al., 2022a). The 55 morphological characters are all somatic, macro-morphological features (Appendix B). These were scored exclusively from adult females because adult male morphology is at least partially adapted for the terrestrial dispersal phase that they undergo, whereas female morphology is more representative of the general morphology of the species (in that juveniles of both sexes resemble adult females) and is presumably adapted to the sedentary lifestyle of the species. Most of our morphological characters correspond closely with those scored in previous morphological analyses of the Mygalomorphae (Bond et al., 2012; Bond & Opell, 2002; Goloboff, 1993, 1995; Raven, 1985), but we have restructured characters following the logic for character/state structure outlined by Sereno (2007) and modified character and state definitions to decrease ambiguity. These previous studies were used extensively during character scoring, with taxon-specific literature and exemplar specimens then cross-checked when available (Wilson et al., 2022a).
BEHAVIORAL CHARACTERS
Retreat construction method: Opportunist – taxa that usually inhabit existing spaces (e.g., cracks and overhangs in embankments, spaces under rocks and within logs) rather than digging/constructing a retreat = 0; obligate burrower – taxa that usually dig their own tubular burrow directly into the substrate = 1; nest-builder – taxa that construct short, silken nests, which are attached directly to the substrate (often on trees, cave walls, or sometimes directly to the ground) = 2.
Retreat entrance, type: web – extensive use of silk outside the entrance to the retreat to form a flat sheet, a funnel, or a space/curtain web = 0; open – an unmodified, circular opening to the retreat (which may temporarily be covered with silk or soil by the spider) = 1; turret – an entrance that is open, but modified to extend from the substrate through the use of silk and/or soil = 2; collar – an entrance that is closable through the use of a silken collar that collapses inward = 3; trapdoor– an entrance that is closed with a ‘door’ constituting an asymmetrical extension of the burrow lining (often mixed with soil and/or humus fragments), allowing the demarcation of one side of the burrow as the ‘hinge’ side = 4; purse – an extension of the burrow lining that lies along the substrate or is attached vertically to a surface, is rough and camouflaged, through which the spider ambushes prey = 5.