Table 1.

Position of the peak workspace and object size for a sample of extant and fossil primate taxa. The real object size corresponds to the object size that is achieved by scaling the relative object size back to real world units. Australopith ‘human’ and ‘Pan’ refer to use of human versus Pan trapeziometacarpal joint range of motion in two separate kinematic models. In Au. sediba MH2, the length of the DP2 was also inferred using both human and Pan DP2/IP2 proportions (see Material and methods).

Taxon	peak workspace	relative object size (R)	real object size R (mm)
haplorhines
Homo sapiens	0.043	0.08	19.00
Pan paniscus	0.029	0.11	28.70
P. troglodytes	0.028	0.10	26.2
Gorilla gorilla	0.031	0.10	28.70
Pongo pygmaeus	0.022	0.14	37.50
Hylobates lar	0.027	0.11	2.20
Papio hamadryas	0.030	0.10	15.60
Macaca fascicularis	0.028	0.10	10.00
Macaca mulatta	0.028	0.10	11.40
Presbytis cristata	0.016	0.16	18.00
Sapajus apella	0.027	0.08	7.90
Cebus albifrons	0.029	0.08	8.70
Alouatta semiculus	0.029	0.08	11.50
Tarsius bancanus	0.023	0.11	5.80
strepsirrhines
Lepilemur leucopus	0.029	0.08	4.00
Propithecus verreauxi	0.029	0.09	9.60
Avahi laniger	0.024	0.11	7.40
Euoticus elegantulus	0.031	0.09	4.20
Loris tardigradus	0.029	0.09	2.90
Nycticebus coucang	0.030	0.09	4.00
Daubentonia madagascariensis	0.029	0.08	10.00
fossils
early H. sapiens Qafzeh 9	0.044	0.08	2.90
early H. sapiens Ohalo II H2	0.042	0.07	2.50
H. neanderthalensis Kebara 2	0.043	0.08	3.00
Au. sediba MH2 (human)	0.044	0.08	2.10
Au. sediba MH2 (Pan)	0.040	0.09	2.40
Au. afarensis comp (human)	0.042	0.08	2.40
Au. afarensis comp (Pan)	0.040	0.08	2.40