Morphometric analysis confirms the presence of the Plains-wanderer (Aves: Pedionomus torquatus) in fossil deposits at Naracoorte Caves, South Australia

Figures & data

Table 1. A list of measurements collected in this study.

Element	Measurement
Humerus	total length (TL), maximum proximal width (PW), proximal length from caput to distal side of crista deltopectoralis (PL), shaft dorsoventral width (SW), maximum distal width (DW), distal craniocaudal depth through condylus dorsalis (DD)
Ulna	total length (TL), maximum proximal width (PW), proximal depth (PD), shaft dorsoventral width (SW), maximum distal width (DW), condylus dorsalis depth (CD)
Carpometacarpus	total length (TL), proximal craniocaudal width (PW), metacarpal II dorsoventral width (M2W)
Coracoid	total length from angulus medialis (TL), proximal width in medial aspect (PW), sternal facet width (SF)
Femur	total length (TL), maximum proximal width (PW), proximal depth of trochanter (PD), shaft dorsoventral width (SW), maximum distal width (DW), maximum distal depth (DD)
Tibiotarsus	total length (TL), proximal lateromedial width across articular surface (PW), shaft lateromedial width (SW), maximum distal width (DW), distal craniocaudal depth of condylus medialis (DD)
Tarsometatarsus	total length (TL), proximal lateromedial width (PW), proximal depth (PD), shaft width (SW), distal width (DW), trochlea metatarsi III width (T3W), trochlea metatarsi III depth (T3D)

Table 2. Mean (in mm), standard deviation, and sample size (n) of all variables measured from Naracoorte fossil Pedionomus, modern Pedionomus torquatus, and Erythrogonys cinctus. Abbreviations follow Table 1.

Element	Measurement	Fossil Pedionomus	Modern Pedionomus	Erythrogonys (n = 3)
Humerus	TL	35.5 ± 1.61, n = 41	33.6 ± 2.28, n = 16	32.5 ± 0.26
	PW	7.2 ± 0.37, n = 45	6.7 ± 0.40, n = 17	7.1 ± 0.25
	PL	10.5 ± 0.66, n = 43	9.7 ± 0.83, n = 17	9.8 ± 0.13
	SW	2.3 ± 0.15, n = 47	2.0 ± 0.18, n = 17	2.1 ± 0.03
	DW	4.8 ± 0.24, n = 43	4.6 ± 0.35, n = 17	4.8 ± 0.16
	DD	2.9 ± 0.18, n = 43	2.9 ± 0.22, n = 17	2.95 ± 0.05
Ulna	TL	40.4 ± 2.14, n = 3	36.8 ± 2.71, n = 18	34.4 ± 0.23
	PW	4.0 ± 0.43, n = 5	3.8 ± 0.32, n = 18	3.7 ± 0.05
	PD	2.9 ± 0.34, n = 5	2.7 ± 0.19, n = 18	3.3 ± 0.33
	SW	1.8 ± 0.23, n = 5	1.6 ± 0.15, n = 18	1.8 ± 0.05
	DW	2.9 ± 0.42, n = 3	2.8 ± 0.21, n = 17	3.4 ± 0.12
	CD	2.8 ± 0.26, n = 3	2.6 ± 0.21, n = 17	2.6 ± 0.06
Carpometacarpus	TL	19.3 ± 0.70, n = 8	18.4 ± 1.18, n = 17	19.6 ± 0.37
	PW	4.3 ± 0.26, n = 10	4.1 ± 0.28, n = 17	4.4 ± 0.10
	M2W	1.5 ± 0.18, n = 10	1.4 ± 0.13, n = 17	1.4 ± 0.03
Coracoid	TL	17.3 ± 0.99, n = 12	16.2 ± 1.38, n = 20	15.0 ± 0.35
	PW	4.0 ± 0.33, n = 12	3.9 ± 0.46, n = 20	3.4 ± 0.38
	SF	4.6 ± 0.18, n = 12	4.1 ± 0.43, n = 16	4.9 ± 0.17
Femur	TL	28.0 ± 0.42, n = 2	27.4 ± 1.80, n = 20	24.9 ± 0.55
	PW	4.6 ± 0.14 n = 2	4.2 ± 0.39, n = 19	4.2 ± 0.16
	PD	3.9 ± 0.04, n = 2	3.6 ± 0.39, n = 20	3.4 ± 0.10
	SW	2.1 ± 0.04, n = 2	1.9 ± 0.17, n = 20	1.9 ± 0.09
	DW	4.8 ± 0.07, n = 2	4.5 ± 0.38, n = 20	4.5 ± 0.03
	DD	3.4, n = 1	3.6 ± 0.31, n = 19	3.5 ± 0.13
Tibiotarsus	TL	39.1 ± 2.18, n = 14	38.6 ± 1.80, n = 17	49.9 ± 1.75
	PW	4.4 ± 0.32, n = 29	3.9 ± 0.32, n = 15	3.8 ± 0.08
	SW	2.0 ± 0.14, n = 34	1.8 ± 0.12, n = 17	1.9 ± 0.08
	DW	4.0 ± 0.30, n = 21	3.8 ± 0.26, n = 16	3.3 ± 0.10
	DD	3.5 ± 0.30, n = 22	3.7 ± 0.21, n = 15	3.6 ± 0.09
Tarsometatarsus	TL	25.4 ± 1.25, n = 15	25.4 ± 1.03, n = 16	40.3 ± 0.75
	PW	4.7 ± 0.31, n = 16	4.6 ± 0.24, n = 16	3.9 ± 0.10
	PD	3.9 ± 0.17, n = 15	3.5 ± 0.18, n = 16	4.0 ± 0.12
	SW	2.1 ± 0.15, n = 21	1.9 ± 0.10, n = 16	1.5 ± 0.09
	DW	4.3 ± 0.28, n = 26	4.2 ± 0.23, n = 15	3.8 ± 0.10
	T3W	1.8 ± 0.13, n = 28	1.7 ± 0.12, n = 16	1.4 ± 0.03
	T3D	2.2 ± 0.14, n = 28	2.1 ± 0.13, n = 14	1.8 ± 0.00

Figure 1. Principal component analyses of forelimb element measurement data from Naracoorte fossil Pedionomus (squares), modern Pedionomus torquatus (dots), Charadrius bicinctus (diamond), and Erythrogonys cinctus (triangles) specimens. A – Humerus; B – Carpometacarpus; C – Coracoid. Abbreviations on biplot follow Table 1.

Figure 2. Principal component analysis of hindlimb element data from Naracoorte fossil Pedionomus (squares), modern Pedionomus torquatus (dots), Charadrius bicinctus (diamond), and Erythrogonys cinctus (triangles) specimens (legend as in Figure 1). A – Tibiotarsus; B – Tarsometatarsus. Abbreviations on biplot follow Table 1.

Figure 3. Principal component analysis of linear measurements of the appendicular skeleton of Naracoorte fossil Pedionomus (square), modern Pedionomus torquatus (dots), Charadrius bicinctus (diamond), and Erythrogonys cinctus (triangles) (legend as in Figure 1). Due to a lack of complete specimens, fossil Pedionomus data represents the mean of all fossil specimens. A – whole dataset; B – measurements of Pedionomus specimens with low (<0.08) coefficients of variation. Biplot data indicate negative PC1 values in Figure A and positive PC2 values in Figure B are primarily driven by large size of width values.