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1 Electronic Supplementar Material (ESM) for: Scaling and mechanics of carnivoran footpads reveal the principles of footpad design Kai-Jung Chi* and V. Louise Roth *To whom correspondence should be addressed. This pdf file includes: Materials and Methods Tables S1.1, S1.2, S1.3, S2.1 igures S1.1, S1.2, S2.1, S3.1, S4.1a-c, S4.2 References in the following sequence: Section 1 (Sec.1): Scaling factors Notes to Table 2: derivations of formulas to calculate predicted values of algebraicallderived scaling factors Tables of empiricall-derived scaling factors (for A,, and k ) and their confidence intervals Table S1.1: b A for broad interspecific sample (used in calculating predictions) Table S1.2: b for largest available sample (used in calculating predictions) Table S1.3: b k of fore and hind m-p pads and their confidence intervals igures illustrating results and consequences of using alternative b A and b - igure S1.1: Area: mass relationship for mechanicall tested subjects igure S1.2: Alternative results, calculated using different b A and b Section 2 (Sec.2): Procedures for assembling area and mass data. Table 2.1: sources of data igure 2.1: comparison of areas obtained from different sources Section 3 (Sec.3): Calculating the distribution of load between fore and hind limbs igure S3.1: schematic representation and calculations for weight distribution Section 4 (Sec.4): Phlogeneticall independent contrasts igure S4.1a-c: Trees used for p.i.c. of broad interspecific sample (n=47) igure S4.2: Tree used for p.i.c. of specimens used for mechanical testing or measuring thickness Supplemental References

2 Section 1. Scaling factors In Table 2 of the text, the notes marked 4 or 4a through 4k refer to the derivations shown below. Derivation of values predicted for the calculated parameters b P, b E, bε, b Δ, b u, and b U are based on the algebraic rearrangement of Eqs. 1-4, the definitions ("defs.") of variables (in Table 1), M, values assumed for b and b A, and the values of scaling factor implied for each hpothesis (as annotated with * in Table 2). The scaling factors for each variable are based on log-transformed values, hence (e.g.) for 4a below: b P = b - b A. 4a oot pressure: P = (def. of P) A 4b A Strain, under H2: = σ = E E 4c Deformation, under H2: 4d Young s modulus, under H3: M A ε (defs. of E and σ ; H2) E M A Δ = ε (defs. of ε, E, and σ ; H2) E σ M A E = (defs. of E and σ ; H3) 4f Deformation, under H3: Δ = ε (def. of ε ; H3) ε ε 4g Young s modulus, under H4: E = k A (Eq. 1; H4) 4h Strain, under H4: 4i Deformation, under H4: A A A M ε = σ = (Eq.2 and def. of σ ; H4) k k k k M Δ = : constant (def. of k ; H4) k 4j Strain energ densit: 4k Strain energ storage: 1 2 u = ε E (def. of u) 2 1 U = Δ 2 k (def. of U) 2 Page 1 of Supplements

3 Table S1.1 : Scaling factors for m-p pad area (b A ) for broad interspecific sample. Bold italicized values in this table are the upper and lower bounds shown in first column of Table 2 and were used to set the boundaries of the green intervals in ig. 3 (for predictions under various hpotheses). INTERSPECIIC SAMPLE (N=47) Total m-p pad area ore m-p pad area Hind m-p pad area ore Hind RMA slope (95% CI) 0.77 ( ) 0.79 ( ) 0.76 ( ) Ranges of RMA slopes obtained using p.i.c. + ( ) ( ) LS slope (95% CI) 0.71 ( ) 0.74 ( ) 0.68 ( ) 0.15 ( )* + phlogeneticall independent contrasts see Sec. 4. * interval excludes 0, indicating scaling of fore- and hindpad areas differ significantl; p=0.04. Page 2 of Supplements

4 Table S1.2 : Scaling factors for m-p pad thickness (b ) for largest available sample (n=14 individuals). Bold italicized value in this table is shown in second column of Table 2. This and the isometric value 0.33 were used to set the boundaries of the green intervals in ig. 3 (for predictions under various hpotheses). ore m-p pad thickness Hind m-p pad thickness ore Hind ore or Average of fore & hind m-p pad thicknesses RMA slope (95% CI) ( ) ( ) ( ) LS slope (95%CI) ( )* N subjects 14 + subjects * interval includes 0, indicating scaling of fore- and hindpad thicknesses do not differ significantl; p= mechanicall-tested subjects plus four subjects available for morphological measurement but not testing (or retesting, in the case of the one dog, for which stiffness data for ore-hind fell > 10 standard errors from mean residuals of regression for the 10 other tested subjects). Sources of the four additional specimens: Canis familiaris (19.1 kg) - Durham Animal Protection Societ; Caracal caracal (18.8 kg), Panthera onca (99.9 kg), Panthera tigris (181.6 kg) Adam Hartstone-Rose (Duke Universit). Table S1.3 Scaling factors for stiffness ( b k ) of fore and hind m-p pads and their confidence intervals. This is the basis for the red () and blue (H) arrows and confidence intervals shown in ig. 3a for b k. MECHANICALLY TESTED SPECIMENS (N=10) RMA LS ORE HIND b k % CI calculated ( ) ( ) bootstrapped ( ) b k % CI calculated ( ) ( ) bootstrapped ( ) Page 3 of Supplements

5 broad sample (n=47): RMA b A = 0.77 least-squares slope (n=47 and n=10) b A = 0.71 mechanicall tested subjects: (n=10) RMA b A = 0.94 (n = 9) RMA b A = 0.90 Log10 (Total M-P Pad Area, mm 2 ) Log 10 (Bod Mass, kg) igure S1.1. Detail of Area:Mass relationship (from ig. 1a) for mechanicall-tested subjects, with regression lines of various slopes superimposed. RMA relationships are shown for broad interspecific sample (gre line) and for mechanicall tested subjects, including (n=10, red) or excluding (n=9, green) the clouded leopard; ordinar least-squares slope (blue) is the same for both broad interspecific and mechanicall-tested samples. Individuall, all tested specimens (red letters) fall within the range of variation exhibited b broad interspecific sample (gre dots). If the clouded leopard (L) is excluded the slope of the RMA line does not appear to change dramaticall, though the change in correlation within the sample is noteworth (r 2 = > r 2 =0.86). C = domestic cat, D = dogs, M = maned wolves, S = spotted hena. Page 4 of Supplements

6 Empirical results (a) Stiffness (k ) (b) Modulus (E ) H2 H3 H4 H H H2 H3 H H Mechanical consequences Strain (ε ) Strain energ densit (u) Deformation (Δ) Strain energ storage (U) H4 H H3 H H2 H H4 H3 H2 H4 H H H H3 H2 H2 RMA scaling factors igure S1.2. Comparison of hpotheses with results calculated using b and b A either from 10 mechanicall tested subjects or from largest sampling available. As in ig. 3, red and blue arrows show results, with mechanical variables calculated for panel (b) using scaling factors b and b A obtained from the 10 mechanicall tested subjects. Here, for further comparison, pale red and blue arrows show an alternative set of extrapolations, using b and b A from the largest samples of individuals available: n=10 for b k (1.05 for forepads and 0.85 for hindpads; Table S1.3), n = 14 for b (0.40; Table S1.2), and n = 47 for b A (0.79 for forepads, and 0.76 for hindpads; Table S1.1). Although these alternative results suggest that strain energ densit (u, a material propert) ma be approximatel constant for hindpads, scaling of another material propert in hindpads, the modulus (E ), is shifted even further awa from constanc (hence H2 still fails). Using different b and b A does not change the values for b Δ and b U, so pale arrows are outlined with the original red or blue. Page 5 of Supplements

7 Section 2. Procedures for assembling area and mass data Table S2.1. Sources of data used for scaling analses on footpad size in 47 digitgrade carnivorans. amil Species Common name N Source * Canidae elidae Haenidae Canis adustus Side-striped jackal 2 a, h Canis familiaris Domestic dog 5 i Canis latrans Coote 6 c, d, f, g Canis lupus Gre wolf 3 c, d Canis mesomelas Black-backed jackal 2 a, h Canis rufus Red wolf 1 c Chrsocon brachurus Maned wolf 2 i Lcaon pictus Wild dog 3 a, b, h Otocon megalotis Bat-eared fox 2 a, h Speothos venaticus Bushdog 1 f Urocon cinereoargenteus Gra fox 6 b, d, f, g Vulpes lagopus Arctic fox 1 d Vulpes macrotis Kit fox 2 b, d Vulpes vulpes Red fox 6 b, d, g Acinonx jubatus Cheetah 3 b, j Caracal caracal Caracal 2 h, j elis catus Domestic cat 3 f, g, i elis lbica African wild cat 2 h, j Lnx rufus Bobcat 12 b, d, g, i Leopardus pardalis Ocelot 7 b, d, i Leopardus tiginus Oncilla 1 f Leopardus wiedii Marga 2 f, i Leptailurus serval Serval 3 a, h, j, Lnx lnx Lnx 2 d Neofelis nebulosa Clouded leopard 2 e, i Panthera leo Lion 3 b, h, j Panthera onca Jaguar 3 b, d, f Panthera pardus Leopard 3 b, h, j Panthera tigris Tiger 4 b, i Panthera uncia Snow leopard 1 i Pardofelis marmorata Marbled cat 1 e Prionailurus bengalensis Leopard cat 1 e Puma concolor Cougar/Mountain Lion 10 b, c, d, f, i Puma agouaroudi Jaguarundi 4 d, f, i Crocuta crocuta Spotted Hena 7 h, i, j Haena brunnea Brown hena 5 h, i, j Proteles cristata Aardwolf 2 h, j Page 6 of Supplements

8 [Table S2.1, cont'd] amil Species Common name N Source * Galerella sanguinea Slender mongoose 1 j Herpestidae Helogale parvula Dwarf mongoose 1 j Herpestes ichneumon Large gre mongoose 1 j Ichneumia albicauda White-tailed mongoose 1 j Mungos mungo Banded mongoose 1 j Paracnictis selousi Selous's mongoose 1 j Rhnchogale melleri Meller's mongoose 1 j Civettictis civetta African civet 1 j Viverridae Genetta genetta Small-spotted genet 2 h, j Genetta tigrina Large-spotted genet 2 h, j * Sources of images or specimens used in measuring paw pad size: a. Cumming & Cumming S1 ; b. Jaeger S2 ; c. Burt & Grossenheider S3 ; d. Kas & Wilson S4 ; e. Pane et al. S5 ; f. Reid S6 ; g. Eder S7 ; h. Smithers & Abbott S8 ; i. Collected b K-J Chi; j. Skinner & Smithers S9. In cases where the mean bod mass data of adult females were unavailable from these sources, we consulted Silva & Downing S10 and Stuart & Stuart S11. Wherever possible, bod masses were directl measured from known subjects. If onl footprint data were available, mass was estimated as the mean for an adult female from a similar geographic region. Total m-p pad area (twice the sum of the area of the main pad of one fore paw and one hind paw) and total foot area (adding in the areas of the digital pads added to those of the main pads) were used in scaling analses. Comparing data from different sources We expected that areas taken from tracks would be greater, and areas taken from formalinpreserved specimens would be smaller, than those taken from unloaded paw pads on live animals. To address this issue before carring out the scaling analses, we took the following precautions to reduce or correct the effects of different tpes of specimen preservation on the size of paw pads: a.) Each frozen specimen was thawed completel before images were taken. b.) Onl three formalin-preserved specimens were included in this stud. All three of these were Haena brunnea, and their areas were in fact larger than the two sets of areas obtained from tracks of this species. Moreover, whether or not the preserved specimens were included in the average used for this species (i.e., regardless of whether just 2 or all 5 values were averaged), the resulting scaling relationship between total m-p pad area and bod mass across all 47 species was identical: log M = 0.71 log A c.) To account for the shrinkage of dried museum skin (pelt) specimens, we calculated a shrinkage factor in the following wa: The total bod length measured on the pelt was divided b that originall recorded b the collector. The shrinkage factor in area can then be calculated as the square of that in the linear dimension, making the assumptions that (i.) Mammalian skin shrinks isotropicall, and (ii.) Because the edge of the pad is tethered b the skin, the shrinkage of the projecting area of the paw pad is directl affected b shrinkage of the skin. The effects were then assessed b comparing paw pad areas in felids, a group from which we had both tracks and pelts across a broad range of bod size. igure S2.1 demonstrates that in felids, corrected m-p pad areas obtained from skin specimens are onl slightl smaller than values measured from paw prints. Page 7 of Supplements

9 d.) Information on whether and to what degree areas measured from tracks differ from those taken directl from unloaded paw pads is not currentl available, and it is not known how those differences, if an, scale with bod mass. No consistent differences were found in comparisons of data from our tested subjects whose pad areas were measured from images of the foot with those recorded for the same species in our broad interspecific sample from tracks. It is known that tracks made on different substrates (fine cla vs. soft soil) and in different orientations (flat, ascending, turning) differ. A stud b van Strien (1986, The Sumatran Rhinoceros Dicerorhinus sumatrensis (ischer, 1814) in the Gunung Leuser National Park, Sumatra, Indonesia; Hamburg: Verlag Paul Pare) extensivel discusses casts of a large number of tracks, and although rhinos are considerabl heavier than the largest carnivorans and their feet are anatomicall different, their total foot area is similar to what would be predicted for an animal of that size from an extrapolation of the scaling relationships for smaller digitigrade animals S27. In his fig van Strien gives summar statistics for the width of the sole (the area most analogous to the carnivoran m-p pad) for a large number of tracks from what is believed to be a single individual, and he reports standard deviations that are on the order of % of the mean. B contrast, among our tested subjects linear measurements on the pads span a range of ~300% and for the broad interspecific sample the range is ~1000% (i.e., a factor of 10); considered another wa, in the broad interspecific sample, among species within the elidae s.d./mean for total paw pad area is 107% and among species within the Canidae it is 106%. An assumption of our stud is that variation in m-p pad area among species of different sizes is much greater than variation introduced b differences in the techniques of measurement, and that it is not biased in a wa that would markedl affect inferences of scaling relationships. 5 Log Total Paw M-P Pad Area Area (mm (mm 2 ) 2 ) 4 3 Tracks Tracks : = 0.79x , : = r x = (r 2 = 0.91) ur_corrected Pelts, corrected : = 0.79x , : = r x = (r 2 = 0.91) ur Pelts : = 0.79x , : = r x = (r 2 = 0.90) Log Bod Mass (Kg) (kg) igure S2.1. Total m-p pad area and bod mass collected from tracks and pelts of some felid species. The data from the pelts are also shown corrected for skin shrinkage. This plot demonstrates that in felids, areas obtained from pelts and corrected are onl slightl smaller than those measured from footprints. Page 8 of Supplements

10 Section 3. Calculating the distribution of load between fore and hind limbs The proportion of the bod weight distributed between the fore and hind feet differs among carnivoran families: approximatel 0.55:0.45 in felids S12, 0.61:0.39 in canids S13, S14, and 0.65:0.35 in haenids. Because the data for haenids are not available in the literature, the were estimated b first obtaining the location of the center of mass in a silhouette taken from a lateral view, and then calculating the proportion of the weight distribution as the inverse of that of the lever arms from the center of mass to the fore and the hind limbs. Detailed calculations for the fore and hind load are shown in igure S3.1. This estimate was considered appropriate for haenids because this method, when applied to felids and canids, ielded results similar to reported values. Center of mass At equilibrium: f. L f = h. Lh W Therefore, L h L f h f igure S3.1. Schematic representation and calculations for weight distribution using a silhouette taken from a lateral view of an animal (shown here is a cat). W: bod weight; f and h, respectivel, are the load exerted on the fore and hind limbs; L f and L h, respectivel, are the lever arms taken from the center of mass to the fore and the hind limbs. Page 9 of Supplements

11 Section 4. Phlogeneticall Independent Contrasts I. Testing for phlogenetic patterning To determine whether log-transformed bod mass (M) and m-p pad area (A), thickness (), and stiffness (k ) are patterned phlogeneticall, we used Continuous (v1.0d13) S15, a computer program for analsis of comparative data that implements a general least squares model S16, S17 to test two hpotheses: (1) λ = 0 (species trait values are independent and phlogenetic correction is unnecessar--this is the equivalent of evolution on a phlogen with star-shaped topolog), and (2) λ = 1 (a Brownian motion model of evolution on the specified phlogen correctl predicts patterns of covariance among species for that trait). The significance of differences between the maximum likelihood estimate of λ and either 0 or 1 was assessed using a likelihood ratio test ( - 2 x log (likelihood ratio); 1-tailed test with 1df under a chi-squared distribution). Parameters κ and δ were assumed to equal 1. The topolog of the phlogen was a composite of those published b Bininda-Emonds et al. S18, Bardeleben et al. S19 (for canids), and Johnson et al. S20 (for felids). Branch-lengths were calculated from the times of divergence indicated b Bininda-Emonds et al. S18, Johnson et al. S20, and Koepfli et al. S21. Each of three trees with alternative phlogenetic placements of Haenidae was examined: Bininda-Emonds et al. S18 (ig. S4.1A), lnn et al S22 (ig. S4.1B), and Johnson et al. S20 (ig. S4.1C). Internal branches inserted to resolve poltomies or linking successive nodes that had been given the same age in Beninda-Emonds et al. S18 were assigned lengths of 100,000, and a date of 130,000 BP was used for divergence of dog (Canis familiaris) from wolf (C. lupus) S23. or the subsamples of taxa represented b specimens used for mechanical testing or scaling of thicknesses, branches linking conspecifics (domestic dogs and maned wolves) were assigned lengths of 10,000, and the trees were pruned down to just the relevant taxa (ig S4.2). or the broad interspecific sampling of bod masses and pad areas (n = 47), all variables showed significant phlogenetic patterning, calling for calculation of phlogeneticall independent contrasts: or all topologies and all log-transformed variables, λ did not differ significantl from a value of 1 (0.21 < p < 0.88) and the difference between λ and 0 was highl significant (p < 10-4 in all instances), even with a Bonferroni correction for multiple comparisons (for each variable, p < would ield p < 0.05 for each tree). or the subsamples used for mechanical testing or scaling of thicknesses, on the contrar, the maximum likelihood estimates of λ for log-transformed values of M; fore-, hind-, and total pad areas; and fore- and hind-pad thicknesses and stiffness all (a.) differed with high significance from 1 (p < 5.0 x 10-5 in each instance; with Bonferroni correction, p < 6.3 x 10-3 for each variable is equivalent to p < 0.05 for each tree), indicating that a constant-variance (Brownian motion) model of evolution on that phlogen would greatl overestimate the covariance among species, and Page 10 of Supplements

12 (b.) did not differ from 0 (p = 1.00 in almost all instances), indicating that these data varied independentl of phlogen. Conventional regression of these variables, without phlogenetic transformation, was therefore appropriate for the subsample used in mechanical testing. To determine whether this assessment was undul influenced b the inclusion of multiple representatives of the two canid species, the tests were re-run on the tree further pruned to include onl the haenid and felids. Values of λ remained indistinguishable from 0 (p = 1), and although differences from 1 did not attain significance, presumabl in part owing to the reduction of power in a test using six or fewer taxa, in all instances p < 1 (and in all but one, p < 0.3) for λ = 1. II. Standardized phlogeneticall independent contrasts or the broad interspecific sample of taxa used to test H 1, standardized, phlogeneticall independent contrasts (p.i.c.) of log-transformed values of m-p pad areas from fore- and hindlimbs, respectivel, were regressed against p.i.c. of log M using Phenotpic Diversit Analsis Programs (PDAP) as implemented in Mesquite S24, S25. or each of three tree topologies showing different phlogenetic positions for Haenidae (ig. S4.1) we considered five sets of branch-lengths (BL) or branch-length transformations: age (or, for internal branches, duration); log-transformed age; ultrametricized log-transformed age; BL = 1; and BL = 1 ultrametricized. (To avoid negative values after logarithmic transformation, age was originall expressed in m x 100 = / 10,000.) A model was judged acceptable if the absolute values of standardized contrasts were not significantl correlated with their standard deviations (p > 0.05, 2-tailed test S26 ). The domestic dog (Canis familiaris) contributed large contrasts because of its relativel large differences in bod mass and footpad area, coupled with its relativel recent divergence from the wolf. This caused more frequent failure of the data to meet diagnostic criteria or produced higher values for the reduced major axis (RMA) slope (b, the scaling factor) when the passed, so analses were also run with dog excluded. In all, diagnostics were run on independent contrasts of the three variables log M, log (orepad area), and log (Hindpad area) for each of 30 different combinations of topolog, branch-lengths, and sets of taxa. In 17 cases (5 of them with domestic dog included) acceptable diagnostics permitted regression of p.i.c. of log (orepad area) vs. log M. Values of the RMA slopes for the forepad ranged from ,. Scaling factors for the 12 relationships between p.i.c. of log (Hindpad area) vs. log M (4 of which included the dog), ranged from RMA coefficients involving p.i.c. of log (orepad area) were greater than those for log (Hindpad area) in all instances in which both could be calculated. Page 11 of Supplements

13 S18 S19 igure S4.1: Tree topologies and branch lengths derived from Beninda-Emonds et al., Bardeleben et al., Johnson et al. S20, and Koepfli et al. S21. Taxa not shown that would join the tree at nodes in positions marked are plantigrade, which is the primitive condition, indicating that digitigrad has arisen phlogeneticall within Carnivora two or more times. C = Canidae, Hp = Herpestidae, V = Viverridae, H = Haenidae, = elidae; species are abbreviated with first 3 letters of genus followed b first 3 letters of specific epithet. S18 igure S4.1a: with placement of Haenidae according to Beninda-Emonds et al. : 1m Urocin Otomeg Vulvul Vullag Vulmac Lcpic Canlat Canlup Canruf Canadu Canmes Chrbra Speove Rhmel Galsan Herich Parsel Ichalb Helpar Munmun Civciv Gengen Gentig Procri Crocro Habru Neoneb Pantig Panunc Panpar Panleo Panonc Parmar Carcar Carser Leotig Leopar Leowie Lnln Lnruf Acijub Pumcon Pumag Priben elcat ellb C Hp V H Page 12 of Supplements

14 S22 igure S4.1b: with placement of Haenidae according to lnn et al. : 1m Urocin Otomeg Vulvul Vullag Vulmac Lcpic Canlat Canlup Canruf Canadu Canmes Chrbra Speove Procri Crocro Habru Rhmel Galsan Herich Parsel Ichalb Helpar Munmun Civciv Gengen Gentig Neoneb Pantig Panunc Panpar Panleo Panonc Parmar Carcar Carser Leotig Leopar Leowie Lnln Lnruf Acijub Pumcon Pumag Priben elcat ellb C H Hp V Page 13 of Supplements

15 S20 igure S4.1c: with placement of Haenidae according to Johnson et al. (2006) : 1m Urocin Otomeg Vulvul Vullag Vulmac Lcpic Canlat Canlup Canruf Canadu Canmes Chrbra Speove Rhmel Galsan Herich Parsel Ichalb Helpar Munmun Procri Crocro Habru Civciv Gengen Gentig Neoneb Pantig Panunc Panpar Panleo Panonc Parmar Carcar Carser Leotig Leopar Leowie Lnln Lnruf Acijub Pumcon Pumag Priben elcat ellb C Hp H V Page 14 of Supplements

16 igure S4.2: Trees for subjects of mechanical testing and measurements of pad thickness: colored labeling of families as in ig.s4.1; thickness was measured on all subjects and red labels indicate mechanicall tested subset; D subscript = dogs, M# = maned wolves, S = spotted hena, C10 = cat, R = caracal, S18 L = clouded leopard, J = jaguar, T = tiger. Solid branches show topolog of Beninda-Emonds. et al. ; dashed lines show branch lengths adjusted to topologies of lnn et al. S22 and Johnson et al. S20 D13 D12 D06 D11 D10 C D09 M26 * M40 S C10 H R L J 5 m T Page 15 of Supplements

17 References S1. Cumming, D. H. M. & Cumming, G. S. Ungulate communit structure and ecological processes: bod size,hoof area and trampling in African savannas. Oecologia 134, (2003). S2. Jaeger, E. Tracks and Trailcraft (Lons Press, New York, 2001). S3. Burt, W. H. & Grossenheider, R. A ield Guide to the Mammals (Houghton Mifflin Compan, 1964). S4. Kas, R. & Wilson, D. E. Mammals of North America (Princeton Universit Press, Princeton, N.J., 2002). S5. Pane, J., rancis, C. M. & Phillipps, K. A ield Guide to the Mammals of Borneo (Sabah Societ, 1985). S6. Reid,. A ield Guide to the Mammals of Central America & Southeast Mexico (Oxford Universit Press, New York, 1997). S7. Eder, T. Animal Tracks of the Carolinas (Lone Pine Publishing, Renton, WA, 2002). S8. Smithers, R. H. N. & Abbott, C. Land Mammals of Southern Africa: A ield Guide (Macmillan South Africa, Braamfontein, Johannesburg, 1986). S9. Skinner, J. D. & Smithers, R. H. N. The Mammals of the Southern African Subregion (Universit of Pretoria, Pretoria, South Africa, 1990). S10. Silva, M. & Downing, J. A. CRC Handbook of Mammalian Bod Masses (CRC Press, Inc., Boca Raton, l., 1995). S11. Stuart, C. & Stuart, T. A ield Guide to the Tracks and Signs of Southern and East African Wildlife (Struik Publishers, Cape Town, South Africa, 2000). S12. Lacquaniti,. & Maioli, C. Independent control of limb position and contact forces in cat posture. Journal of Neurophsiolog 72, (1994). S13. Alexander, R. M., Bennett, M. B. & Ker, R.. Mechanical properties and function of the paw pads of some mammals. Journal of Zoolog, London 209, (1986). S14. Lee, D. V., Bertram, J. E. & Todhunter, R. J. Acceleration and balance in trotting dogs. Journal of Experimental Biolog 202, (1999). S15. Pagel, M. (2001). S16. Pagel, M. Inferring evolutionar processes from phlogenies. Zoologica Scripta (Journal of the Roal Swedish Academ) 25th Anniversar Special Issue on Phlogenetics and Sstematics 26, (1997). S17. Pagel, M. The maximum likelihood approach to reconstructing ancestral character states of discrete characters on phlogenies. Sstematic Biolog 48, (1999). S18. Bininda-Emonds, O. R. P., Gittleman, J. L. & Purvis, A. Building large trees b combining phlogenetic information: a complete phlogen of the extant Carnivora (Mammalia). Biological Reviews 74, (1999). S19. Bardeleben, C., Moore, R. L. & Wane, R. K. A molecular phlogen of the Canidae based on six nuclear loci. Molecular Phlogenetics and Evolution 37, (2005). S20. Johnson, W. E. et al. The late Miocene radiation of modern elidae: a genetic assessment. Science 311, (2006). S21. Koepfli, K.-P. et al. Molecular sstematics of the Haenidae: Relationships of a relictual lineage resolved b a molecular supermatrix. Molecular Phlogenetics and Evolution 38, (2006). Page 16 of Supplements

18 S22. lnn, J. J., inarelli, J. A., Zehr, S., Hsu, J. & Nedbal, M. A. Molecular phlogen of the Carnivora (Mammalia): Assessing the impact of increased sampling on resolving enigmatic relationships. Sstematic Biolog 54, (2005). S23. Vilà, C., P., et al. Multiple and ancient origins of the domestic dog. Science 276, (1997). S24. Maddison, W. P. & Maddison, D. R. Mesquite: A modular sstem for evolutionar analsis. Version (2006). S25. Midford, P. E., Garland, T. J. & Maddison, W. P. PDAP Package (2003). S26. Garland, T., Jr., Harve, P. H. & Ives, A. R. Procedures for the analsis of comparative data using phlogeneticall independent contrasts. Sstematic Biolog 41, (1992). S27. Chi, K.-J. unctional morpholog and biomechanics of mammalian footpads. Ph. D. dissertation, Duke Universit, Durham, NC, USA (2005). Page 17 of Supplements