Ungulate-Like Mammals from the Late Cretaceous of
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Supplementary Information for “Late Cretaceous relatives of rabbits, rodents, and other extant eutherian mammals” Nature 414, 62 Matrix of taxa, characters, and states defined below and used in the phylogenetic analyses in Fig. 3 Characters >>>> Alostera saskatchewanensis Asioryctes nemegtensis Aspanlestes aptap ???11 Avitotherium utahensis Barunlestes butleri Batodon tenuis Cimolestes spp. Daulestes nessovi Eoungulatum kudukensis Gallolestes spp. Gypsonictops spp. Kennalestes gobiensis Kulbeckia kulbecke Mimotona spp. Murtoilestes abramovi Otlestes meiman Oxyprimus spp. Paranyctoides spp. Parazhelestes minor Parazhelestes robustus Prokennalestes spp. Protungulatum spp. Tribosphenomys spp. Zalambdalestes lechei Zhelestes temirkazyk 1-5 ????? 20003 6-10 ??111 10010 00??1 11-15 21010 10010 00000 16-20 11112 00003 10010 21-25 11201 10000 01102 26-30 24??? 40000 11101 31-35 ????? 00000 24??? ????? 51113 2???? 20?12 11?10 0???1 ?0??? 10?13 10002 20103 50123 ?0??? 00??? 20??2 00??1 0???1 01??1 00??0 20?12 50120 31103 00?11 ?0200 10110 ?0110 10010 1?000 00100 ????0 10110 10000 11010 1A121 ??000 ??010 10110 00000 00300 00100 00000 11110 2?121 10110 00100 01010 20011 10010 10010 10011 11010 ????0 10010 10010 11011 20011 00010 00010 10010 12A10 11010 11010 00100 11010 20011 20011 11010 01112 1110? 01002 00001 00001 01122 ????1 10102 00002 11101 11122 00000 00102 11120 00101 01122 01122 00000 11120 11122 1110? 011?2 11101 ?1000 11000 20000 20000 11322 1?201 11000 20000 21000 31101 00000 11000 01322 10201 11211 11311 00000 01323 21111 ?1000 1?101 23??? 00111 22??? DD??? 00??0 34000 2C??? 12??0 12000 01111 34111 00??? 00000 34??? 22??? 24000 34000 00??? 34000 34111 00111 34000 ????? ?2?10 ???10 0??10 00000 ?0011 ????? ?0010 00000 11100 13122 ????? ?0010 ???10 ????0 ?0011 ?0011 ?0?00 00010 13122 12?10 00011 Characters >>>> Alostera saskatchewanensis Asioryctes nemegtensis Aspanlestes aptap 10010 Avitotherium utahensis Barunlestes butleri Batodon tenuis Cimolestes spp. Daulestes nessovi 36-40 ????? 00001 41-45 ????? 00100 00100 46-50 ?0?01 01111 10021 51-55 1??0? 00002 11201 56-60 ????? 11100 12210 61-65 ????? 01011 11220 66-70 ????? 10111 ?0100 ????0 20221 01000 A1A2A ??0?0 02??? 00132 ?01?0 00A00 00??? 11?01 11212 00101 A0001 01201 1220? 1??02 1110? 00002 02000 ????? 11411 ??32? 112B0 00220 ????? 11011 ????? ????? ?1010 ????? 12??? ????? ????? 0??0? Supplementary Information: Eoungulatum kudukensis Gallolestes spp. Gypsonictops spp. Kennalestes gobiensis Kulbeckia kulbecke Mimotona spp. Murtoilestes abramovi Otlestes meiman Oxyprimus spp. Paranyctoides spp. Parazhelestes minor Parazhelestes robustus Prokennalestes spp. Protungulatum spp. Tribosphenomys spp. Zalambdalestes lechei Zhelestes temirkazyk LK relatives of rabbits, rodents, & other extant eutherians 0001? ????? 000B0 00020 1002? 22220 ????? 00000 01021 00010 00010 00010 00010 0102A 2222? 10021 ??010 0???? ?0131 01132 00000 ??131 22131 ????? 01131 001E1 00101 10021 10021 00000 00121 ??021 00132 10021 11101 11101 11201 01101 11211 123?2 ???01 01201 10001 0110B 11101 11101 00000 10101 123?2 11212 11101 13110 1BB1? 12A02 00002 13102 1310? ???0? 01001 1320? 1EDA? 13110 13110 00000 13201 1310? 13002 1311? 1122? ?1?0? 11220 11220 11211 11411 ????? 0030? 11?10 ?120? 11220 11220 00000 11100 11421 11211 11220 Archibald et al 2 ?0100 ????? ????? 01011 01011 2???? ????? ????? ????? ????? ?0100 ?0100 ?0000 01010 ????? 11011 00100 10010 ????? ????? 1?111 11111 ????? ????? ????? ????? ????? 10010 10010 00010 00110 ????? 12111 10010 Characters and characters states for the taxa above and used in the phylogenetic analysis in Fig. 3. Ancestral state = 0, derived = 1-5, missing data = ?. For polymorphic characters, the following abbreviations were used: A = 0&1, B = 1&2, C = 2&4 D = 0&2, E = 2&3. The phylogenetic analyses used MacClade and PAUP*. We utilized 70 characters including those from previous studies (Wible et al., in prep. and refs. 1, 10, 23, & 24) based upon upper and lower dentitions, anterior skull, dentary, and petrosal. Only multistate characters forming a morphocline were coded as ordered and are so indicated. All characters were unweighted. The branch and bound search option was used for each analysis. A full heuristic search was used for bootstrap analyses. Only values over 50 are shown in Fig. 3. Species level taxa were used in preparing the matrix. When multiple species in a particular genus were used they are so indicated by the designation "spp." Polymorphisms in such taxa indicate interspecific variation. Polymorphisms within a named species indicate intraspecific variation. Specimens or casts of all taxa used in this study were examined by one or more of the authors and were supplemented by references listed below. Dentaries and petrosals are identifiable to Dzharakuduk "Zhelestidae" and referable to named taxa on the basis of size. Petrosals of Dzharakuduk Kulbeckia are identifiable based on work on zalambdalestids and Prokennalestes by Wible et al. (2001) and Wible et al (in prep.). Trees were rooted using Murtoilestes and Prokennalestes as outgroups. The decision to order characters was not taken lightly. We ordered 27 of the 37 multistate characters. This was only done in instances where we felt there was compelling biological evidence for a transformational series. A common fallacy is that not ordering has fewer Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 3 assumptions than ordering. The argument goes that by not ordering one is not making an assumption about the path of evolution. Not ordering is the default setting in PAUP* and MacClade, but it does not have fewer assumptions than ordering. Campbell and Frost (1993) have discussed this issue at some length and conclude, given a transformational series showing intermediate conditions, that ordering such a series is as (or more) justified than not ordering. We performed a run of the second analysis shown in Fig. 3b with all characters unordered (heuristic search with 1000 replicates and the stepwise-addition option). As in Fig. 3b, the result was a strongly supported (bootstrap value > 70) "zalambdalestid" plus Glires clade and a more weakly supported (bootstrap value < 70) "zhelestid" plus archaic ungulate. Explanation of characters and state changes UPPER & LOWER DENTITION COMBINED 1) Number of upper and lower premolars: 5/5 (0), 4-5/4-5 (1), 4/4 (2), 3-4/4 (3), 3/4 (4), 2-3/1-3 (5). Ordered. There is mounting evidence that the ancestral premolar count in eutherians is five over five (Novacek, 1986; Archibald, 1996; Archibald and Averianov, 1997, 1998; Nessov et al., 1998). If only uppers or lowers were known for a particular taxon, the other portion of the dentition was similarly coded. As a separate paper is in preparation dealing with the specifics of the ancestral premolar formula (Archibald and Averianov, in prep.) we provide only a brief review. The mid-Cretaceous eutherians Prokennalestes and Otlestes had five premolars in which the third position was similar in size or only slightly smaller than the second position. The midLate Cretaceous Asian "zhelestids" also possessed five premolars (e.g., Nessov et al., 1998) as did the questionable insectivoran Paranyctoides aralensis (Archibald and Averianov, in press), although the third premolar is invariably reduced relative to the second position in these taxa. The reason for arguing that this reduced tooth is the third premolar (or dp3) rather than a retained dp2, is that there is some evidence for replacement of site 2 and the presence of the small p3 (or dp3) in a few zhelestid individuals (Archibald and Averianov, in prep.). In some taxa such as Daulestes and Kennalestes either an extra upper or lower premolar may be present. These have been interpreted as retained deciduous teeth. In Gypsonictops a smaller tooth in position three is also variably present, but probably on a more regular basis. In older individuals it appears to be shed. In the majority of other Late Cretaceous eutherians the premolar dental count is four over four. Finally, among the most derived zalambdalestids the number of upper premolars varies from three to four in Zalambdalestes to only three in Barunlestes Wible et al. (in prep.). Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 4 Although we now find substantial evidence that having five premolars is ancestral for eutherians, we have not yet published our conclusions. Accordingly, we also ran both of the analyses in Fig. 3 with the assumption that having four premolars is ancestral for eutherians and that the fifth position is a retained deciduous tooth. This was coded as number of upper and lower premolars: 4/4 (0), 5/5 (1), 4-5/4-5 (2), 3-4/4 (3), 3/4 (4), 2-3/1-3 (5). It was run unordered. Other than Kennalestes and Cimolestes clustering in the equivalent analysis to that in Fig. 3a, there were no topological differences in either analysis. Character 1 in Rougier et al.'s supplementary information (1998) dealt with the premolar count. The only difference is that while they used strict counts of five (0), four (1), three (2), and less than three (3); we chose to more finely subdivide the character, including variation seen in a given taxon (e.g., 4-5/4-5). We differed from these authors only for Kennalestes, where we coded it as 4-5/4-5 (1) premolars and Zalambdalestes as 3-4/4 (3) following the more recent work of Wible et al. (in prep.). There is a persistent issue with how to code characters that vary within a taxon, most particularly within in a species. We could have coded the characters as in Rougier et al.'s supplementary information (1998), i.e., as strict counts, and then coded species that vary as polymorphic. This would not help in the analysis. In this instance a case can be made that individual taxa do have varying states for individuals. If it is common enough, coding this as a variable character state is as valid as trying to pigeonhole it into a constant state (4, 5, etc.). Humans commonly have agenesis of the third molar. At what point would it be reasonable to code the number as of molars as 2-3 in humans? We submit that for the taxa in this study, having a variable number of premolars is very common or else it would not show up so frequently in the small sample sizes available. We note that this is true whether the trend is to reduce and lose a premolar site (as we argue) or whether some taxa retain a deciduous premolar. 2) M3/m3 size relative to other M2/m2: not noticeably reduced (0), reduced (1). This simply relates to the reduction in size of M3/m3 relative to M1-2/m1-2. This is similar to character 41 in Rougier et al.'s supplementary information (1998) except that they specified the width of the last upper molar relative to the penultimate molar. We generalized this to size so that m3 could also be compared to m2 for taxa in which M2 and M3 are not known. UPPER ANTERIOR DENTITION 3) Relative sizes of upper incisors: none are markedly larger than surrounding incisors (0), one or two are markedly larger than surrounding incisors (1). Although the total number of Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 5 incisors most often cannot be determined for most taxa, enough preserve teeth or alveoli in this region so that any clear disparities in upper incisor size can be seen. 4) Number of upper canine roots: two (0), one (1), canine absent (2). Ordered. This is the same as character 10 in Rougier et al.'s supplementary information (1998). UPPER PREMOLARS 5) Protocone on P4 (= penultimate premolar): none or very little (0), slight swelling (1), greatly smaller than in P5 (2), only slightly smaller than in P5 (3). Ordered. This is a quite straightforward transformation series of the expansion of the protocone on the penultimate premolar. This is the same as character 12 in Rougier et al.'s supplementary information (1998) except that they recognized one less state. For those taxa in common to both studies, the characters were coded the same. 6) Roots on P4 (= penultimate premolar): two roots (0), three roots (1), one root, sometimes bifurcated (2). Ordered. This is the same as character 13 in Rougier et al.'s supplementary information (1998) except that they recognized one less state. For those taxa in common to both studies, the characters were coded the same. 7) Metacone or metaconal swelling on P5 (= ultimate upper premolar): present (0), absent (1). Even if there was only a swelling detected on the postparacrista of the ultimate premolar (which we designate as P5) the taxon was considered as having this character state. We considered this the ancestral state, because even the earliest accepted eutherian preserving P5 (Prokennalestes spp.) has some metaconal swelling on P5. This reverses the polarity assessment of this character as given in Nessov et al. (1998). Archibald (1996) and Nessov et al. (1998) scored Zalambdalestes as having a metaconal swelling on the last upper premolar, the condition noted by Kielan-Jaworowska (1969). In contrast, Barunlestes was scored as not having a metaconal swelling. As Wible et al. (in prep.) note, this does not agree with Kielan-Jaworowska and Trofimov (1980) who indicated that an incipient metacone occurs on the ultimate premolar in Barunlestes and that it is somewhat larger and more strongly pronounced than it is in Zalambdalestes. We concur with Wible et al.’s (in prep.) assessment. UPPER MOLARS Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 6 8) Stylar shelf on M1&2: on both M1&2 widest point of stylar shelf (centrocrista to greatest labial extent) equal or greater than 29% of total crown width (0), on both M1&2 widest point of stylar shelf (centrocrista to greatest labial extent) from 19% to 27% of total crown width (1), on M1 widest point of stylar shelf (centrocrista to greatest labial extent) equal or greater than 29% of total crown width and on M2 widest point of stylar shelf (centrocrista to greatest labial extent) from 19% to 27% of total crown width (2), on M1 widest point of stylar shelf (centrocrista to greatest labial extent) from 19% to 27% of total crown width and on M2 widest point of stylar shelf (centrocrista to greatest labial extent) equal or greater than 29% of total crown width (3). There is a general trend in therian molar evolution to narrow the stylar shelf relative to the total width of the crown. The eutherians studied here are somewhat intermediate in this trend. In order to quantify the size of the stylar shelf we measured from the anteroposterior midline of the paracone and metacone (approximately the centrocrista) to the most labial edge of the molar. This has the advantage of repeatability, but the disadvantage of including a portion of the labial portions of the paracone and metacone in the measurement. We felt the former outweighed the latter. These measurements were taken as a percentage of the greatest linguolabial width of the crown. The demarcation of groups was somewhat arbitrary, but we felt justified in recognizing two groups for both M1 and M2. For the few cases when the two tooth sites fell in different groups, we treated these taxa as additional character states. Measurements are available from the first author. The width of the stylar shelf was coded as wide (0) or narrow (1) by Archibald (1996) and Nessov et al. (1998). These authors indicated that Zalambdalestes is polymorphic. Wible et al. (in prep.) coded the stylar shelf as narrow for this taxon. We concur. It was because of the difficulty of assessing this character that we introduced the above quantification. A related and even more difficult character to assess is the depth of the ectoflexus. Archibald (1996) and Nessov et al. (1998) coded the ectoflexus as deep (0), shallow (1), or none (2). These authors scored Zalambdalestes as having a deep ectoflexus and Barunlestes as polymorphic (deep and shallow). Wible et al. (in prep.) were uncertain as how to evaluate this character, as the ectoflexus varies from tooth to tooth. Nevertheless, they felt that the condition in Zalambdalestes resembles that in Barunlestes, Gypsonictops, and Cimolestes, all of which were said to be both deep and shallow (0 and 1), and thus they scored Zalambdalestes similarly. We concur with the difficulty of evaluating this character. We attempted to quantify this character for M1 and 2, but found that the variation was greater than could be accounted for within the coding we used. This Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 7 character merits further study but we felt it best to exclude it from our analysis. Rougier et al.'s supplementary information (1998) coded the ectoflexus in their character 19. 9) Number of cuspules in the parastylar region: two (0), one (1), none (2). These two cusps were referred to as the preparastyle and parastyle (cusp A) by Kielan-Jaworowska and Dashzeveg (1989). Nessov et al. (1998) and Rougier et al.'s supplementary information (1998) coded this in the reverse order shown here. Although we cannot be certain, we feel that the presence of two cusps in the parastylar region as found in our two outgroup taxa, Prokennalestes spp. and Murtoilestes abramovi and the earliest Late Cretaceous Otlestes is a better assumption for the ancestral condition. 10) Parastylar groove: moderately to well-developed (0), very reduced or absent (1). This relates to the decrease in shear in this part of the crown. The groove is most obviously developed in taxa in which the parastylar lobe is large and distinctly positioned anterior to the paracone. We coded it as reduced or absent only in those taxa where the parastylar lobe was absent or reduced and positioned more anterolabially. 11) Stylar cusp A (parastyle): distinct, but smaller than B (0), subequal to larger than B (1), very small to indistinct (2). M2 considered when available. This is character 20 in Rougier et al's. supplementary information (1998). These authors assessed both Otlestes and ZhelestesAspanlestes as having state "0." Although the single upper dentition of Otlestes is somewhat worn, we concur with this assessment. For all zhelestids except Alostera and Avitotherium, however, we feel that the state is best assessed as "1." 12) Stylar cusp C: absent (0), variably present and if so small (1), present (2). Ordered. This is character 23 in Rougier et al's. supplementary information (1998) but with a third character state added. 13) Stylar cusp D: absent (0), smaller or subequal to B (1). This is character 24 in Rougier et al's. supplementary information (1998). We excluded their character state 2 (stylar cusp D larger than B) as this does not occur in any of our taxa. Most of the Asian zhelestids variably have a very small cuspule or small thickening in the region of the stylar cusp D region, but we elected to treat it as absent in these taxa. 14) Stylar cusp E: distal to D (0), small to absent (1). This is character 25 in Rougier et al's. supplementary information (1998). We excluded their character state 0 (stylar cusp E directly lingual to D or D position) and recoded our states a "0" and "1" as this does not occur in any of our taxa. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 8 15) Size and labial extent of metastylar lobe relative to parastylar lobe on M2: metastylar lobe of similar size and labial extent (0), metastylar lobe of smaller size and not extended as labially as parastylar lobe (1). This character was assessed in occlusal view with the paracone and metacone as the axis of alignment. In Rougier et al.'s supplementary information (1998) their character 18 concerns the "metastylar area on penultimate upper molar" and was coded as large or reduced. The seven eutherians they included were all coded as ancestral, while we coded Zalambdalestes as derived (as well as taxa they did not include – other zalambdalestids, Tribosphenomys and Daulestes). Although these differences may be the result of differing opinions on coding this character, we surmise that the characters in fact are not the same. While we agree that the metastylar lobe is not completely reduced in, for example, the zalambdalestids, its labial margin is nonetheless positioned more lingually than that of the parastylar lobe. 16) Metacingulum: formed only of the postmetaconule crista and terminates dorsal of postmetacrista, which is continuous with the metastylar lobe (0), formed of the postmetaconule crista continuing on to the metastylar lobe, but posterior margin of metacone sometimes interrupts this connection (1). This character was shown in fig. 23 of Nessov et al. (1998). Ancestrally in eutherians the postcingulum (when present), the postmetaconular crista, and postmetacrista plus metastylar lobe form three en echelon ridges from the lingual to the labial side along the posterior margin of the molar (Nessov et al., 1998: fig.23). Later, probably independently, the postmetaconular crista joins the metastylar lobe in the same plane (Nessov et al., 1998: fig.23). Finally, over time, the postcingulum joins the same plane so that there is a continuous ridge or shelf from the lingual to the labial edge of the crown. This last state is not achieved in any of the Late Cretaceous eutherians that we are considering. This appears to be the same character Cifelli (1993) defined as separately evolving in metatherians. What he referred to and pictured (fig. 14.2) as the postprotocrista is what we here term the postmetaconular crista. We have, however, coded them in the same manner. His postprotocrista not extending "labially past base of paracone" is the same as our state "0" and his postprotocrista extending "labially past base of paracone" is the same as our state "1." Clearly, state "1" evolved separately in metatherians and eutherians. Rougier et al.'s supplementary information (1998) used Cifelli's character as their character 34 although they incorrectly coded the seven eutherians they included as state "1" while all but Zalambdalestes and leptictids are ancestral for this character. 17) Height and size of para- and metacone: paracone higher and larger (0), cusps of similar height and size (1). In Late Cretaceous eutherians, the metacone may be slightly lower and Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 9 of slightly less girth than the paracone; however, the distinction that is made here is between the clearly more ancestral therian condition in which the metacone is always shorter and of less girth than the paracone. It may also slant somewhat posteriorly. Character 27 in Rougier et al.'s supplementary information (1998) is essentially the same as our character 17, although they recognized three states. There is, however, complete agreement in the coding of taxa found in both studies. 18) Base of paracone and metacone: merged (0), separate (1). The ancestral therian state appears to be with the metaconal base partly appended to the posterior side of the paraconal base, and with the metacone smaller and slanted posteriorly. Although the separation of the bases of theses cusps and the increase in size of the metacone (character 17) seem to be related, they by no means occur together. Archibald (1996) and Nessov et al. (1998) also coded the base of the paracone and the metacone as either merged (0) or separate (1). These authors scored the base of the paracone and metacone as separate for Zalambdalestes (as did Rougier et al. supplementary information (1998) character 30) and as merged for Barunlestes. Wible et al. (in prep.) scored the paracone and metacone as separate in Barunlestes. This was based upon the statement in KielanJaworowska and Trofimov (1980) that teeth of Barunlestes do not differ in any details from those of Zalambdalestes and stereophotographs of Barunlestes in Kielan-Jaworowska and Trofimov (1980: plate 2, fig. 1b, PIN 3142-701 in). We concur. From our observations of the original material, the paracone and metacone are separate in Otlestes rather than being merged as indicated in Rougier et al.'s supplementary information (1998). 19) Distance between paracone or metacone and protocone relative to total anterior or posterior width, respectively: between 45-55% of crown width (0), more than 55% of crown width (1), less than 45% of crown width (2). This concerns the width of the crown between the primary trigon cusps relative to the total width of the crown. The former width is related to character 24 (amount of labial shift of protoconal apex), however, in character 19 we are interested in the degree of approximation of the paracone or metacone with the protocone related to the complete width of the crown and not just the degree to which the protocone may have shifted labially, as was the case for character 24. 20) Relative position of paraconule and metaconule on M1-2: both positioned in nearly same labiolingual plane nearer protocone (0), paraconule positioned distinctly closer to protocone and metaconule nearer midpoint or even nearer metacone (1), both positioned in nearly same labiolingual plane at midpoint or closer to paracone and metacone (2), positioned in near midpoint Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 10 but metaconule very small or absent (3). In Nessov et al. (1998: p. 75, character 18) assessed the "position of conules (especially paraconule) relative to paracone and metacone versus protocone: conules closer to mid-position (0), conules closer to protocone than to the mid-position (1)." We reassessed the condition based on figures in Kielan-Jaworowska and Dashzeveg (1989) and on casts referred to species of Prokennalestes, as well as on specimens of Murtoilestes abramovi (Averianov and Skutschas, 2000, 2001). Based on these examinations, we feel the ancestral condition for eutherians is best regarded as both conules being positioned closer to the protocone. As indicated in the above list of derived states, both conules are variously shifted labially and in one taxon (Asioryctes), the metaconule may be reduced or lost. Character 35 in Rougier et al.'s supplementary information (1998) also deals with the size and disposition of the conules. There authors were interested in other therians and thus their coding of this character reflects this (e.g., conules absent), while our coding included a more finely graded sorting of the conular condition in only eutherians. Thus, while not strictly comparable, from what can be compared, there are not obvious differences in coding. 21) Each internal crista, notably the postparaconular crista: not distinct but forms continuous convex surface with convex or flat conular basin (0), forms distinct wall (winglike) delineating a flat or convex conular basin (1), forms distinct ridge delineating a distinctly concave conular basin (2), very reduced or absent (3). Nessov et al. (1998) gave the conditions of the postparaconular and premetaconular cristae (their character 3) as either strong and wing-like (0) or weak or absent (1). In the same examination of the conules discussed under character 21 we found that the polarity assessment of Nessov et al. (1998) for the condition of the internal cristae is most likely opposite the true polarity. In our outgroup taxa, as well as in other early therians, internal cristae are not distinct but each forms a convex surface merging with the basically flat conular basin between the paraconule and paracone or metaconule and metacone. From there it appears that two possible patterns evolved -- either distinct winglike cristae delineating flat or convex conular basins, or low, distinct cristae delineating distinctly concave conular basins. 22) Height of protocone relative to paracone and metacone: protocone distinctly lower (0), cusps of similar height (1). Viewed from anteriorly or posteriorly, we assessed whether the unworn protocone was distinctly lower than the paracone and metacone or whether the cusps were close to each other in height. This is character 38 in Rougier et al.'s supplementary information (1998). Our coding differed in that we coded Kennalestes and Asioryctes (their Asioryctidae) as Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 11 ancestral for this character while they coded it as derived. Also they were unable to code for Otlestes, which we found to be ancestral for this character. 23) Amount of antero-posterior expansion of protocone: none (0), slight (1), moderate (2), substantial (3). This was character 1 in Nessov et al. (1998). Ordered. This character is related to our character 25, shape of molar crown in occlusal view, but there is not a direct one-toone correlation. For character 23, taxa may show some anteroposterior expansion while not changing overall crown as significantly. This seems to be related to the degree of lingual expansion of the crown. 24) Amount of labial shift of protoconal apex: none (0), moderate (1), substantial (2). Ordered. This was character 2 in Nessov et al. (1998), although in their table 3 it was not specified that it was the shift of the apex and not the entire cusp. In their fig. 21 the labial shift of the protoconal apex is shown for species of Parazhelestes and Eoungulatum, which are the only Cretaceous taxa in our analysis that show this trend. 25) Shape of molar crown in occlusal view: triangular (0), trapezoidal (1), subrectangular (2), rectangular (3). Ordered. As noted above, this character appears related to character 23, the anteroposterior broadening of the protocone. In the present character, however, the form of the crown also relates to the linguolabial expansion of the crown such that only relatively wide molars of Late Cretaceous eutherians take on the more trapezoidal or subrectangular outline. In Rougier et al.'s supplementary information (1998) their characters 15 and 16 (modified after Cifelli, 1990) also relate to shape of the upper molar. They were, however, examining widely among tribosphenic mammals while our work is restricted to eutherians. Not surprisingly, all seven eutherians they sampled had the same derived states for both of their characters 15 and 16. Our attempt at codifying molar crown shape in characters 23 and 25 more finely subdivides eutherians. 26) Constriction of crown through conular region with or without cingulum(a): no constriction & no cingulum(a) (0); marked constriction & with cingulum(a) (1), slight constriction & with cingulum(a) (2), no constriction & with cingulum(a) (3), some constriction & no cingulum(a) (4). This relates to the shape of the outline of M1 and 2 through the mid-region of the crown in occlusal view. Rather than describing the shape we chose to describe the parts of the crown that we believe affect the shape, namely, the combined effects of the addition of cingula and expansion or reduction through the conular region. 27) Pre- and/or postcingula: usually absent (0), crenulations or linguolabially narrow cingula present (1), cingula do not reach or extend below the conules (2), cingula variably reach or Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 12 extend below the conules (3), cingula reach or extend below the conules (4). Ordered. A character very similar to this was coded as character 39 in Rougier et al.'s supplementary information (1998). Our coding recognized five states while theirs recognized only two states, absence and presence of what they termed protocingula. LOWER ANTERIOR DENTITION 28) Lower medial incisor: not enlarged (0), markedly enlarged (1). For this character, it was assessed whether the medial incisor or its alveolus was clearly, and markedly larger than other lower incisors. The medial upper incisor was not considered for this character as too few taxa preserve either this tooth or its alveolus. 29) Lower medial incisor: not procumbent (0), procumbent (1). Incisors that project predominantly vertically or slightly antero-vertically from the dentary are not procumbent. Incisors that project primarily in an anterior direction from the dentary (even if the anterior portion of the incisor recurves vertically) are deemed as procumbent. Very often procumbent incisors are also markedly increased in size, but this is by no means always the case (e.g., most strepsirhine primates). 30) Lower medial incisor: not with restricted enamel (0), with restricted enamel (1). This refers to whether the circumference of the exposed crown is completely encircled by enamel or whether the more lingual or lingual and posterior (or lingual and dorsal on a procumbent incisor) have little or no enamel. 31) Enamel extends to near base of root of enlarged lower (and/or upper) incisor: no (0), yes (1). Wible et al. (in prep.) report that originally they did not believe that enamel extends to near the base of root in Zalambdalestes. They now report that for one specimen of Zalambdalestes "enamel [is] continuous from the crown to the root." 32) Root of lower medial incisor (i1?): not extended posteriorly below p1 (0), extending posteriorly below p1 (1), extending posteriorly below p3 or 4 (2), extending posteriorly beyond p4 (3). Ordered. 33) Lower medial incisor: root not with large apical opening (0), root with large apical opening (1). Two extremes in mammal teeth are those that upon eruption nearly close the base of the root so that only a small opening transmits blood vessels and nerves, versus those that upon eruption retain a very large opening. In the former case, as eruption occurs and the apical opening decreases in size, no more enamel or dentine is laid down. In the latter case, enamel and dentine Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 13 are continuously added, often throughout the life of the mammal (hypselodonty). Certainly, in the former case, the apical root opening may remain enlarged in early stages of eruption. Three specimens of Kulbeckia preserve the medial lower incisor minus the tip. In one that had much of the bone removed (URBAC 98-3), the enlarged, procumbent medial incisor had clearly begun to erupt, although the tip was missing, and it had a root with a large apical opening at its apex. It is also worth noting that enamel comes to within a few millimeters of the root tip. This condition has been reported for Zalambdalestes by Wible et al. (in prep). Based upon the early stages of eruption of more posterior teeth, this is not an adult. It is possible that the apical root opening of the medial incisor would decrease in size later in life, but the tooth had clearly begun erupting and probably was functioning. A large apical root opening in an erupting and functioning tooth is infrequent in non-hypselodont mammals. Without a growth series one cannot determine if the tooth was truly ever-growing. Thus, we have selected the more neutral dichotomy of "root not with large apical opening" versus "root with large apical opening." 34) Number of lower canine roots: two (0), one (1), canine absent (2). Ordered. This is the same as character 44 in Rougier et al.'s supplementary information (1998) except that they referred to the states as biradiculated and uniradiculated and recognized one fewer state. In this study the lower canine was argued to go from two roots to one at the Zatheria node (Peramus and therians). This character appears to switch back and forth between major clades so one cannot confidently establish what is ancestral for any given major clade. In only one of our outgroups, Prokennalestes is the condition known to be two (or bifurcated) roots on upper and lower canines. If our other outgroup Murtoilestes had this region of the dentition preserved and was like Prokennalestes, we would we have a doublet that adds strength to the "two roots is ancestral" argument for eutherians. We are relying on the admittedly weak argument that one outgroup shows this condition. LOWER PREMOLARS 35) First lower premolar: oriented in line with jaw axis (0), oblique (1), p1 absent (2). Ordered. This is character 45 in Rougier et al's. supplementary information (1998). Although we agree with their polarity assessment, we are do not agree with the assessment of Prokennalestes as having state "1." Sigogneau-Russell et al. (1992) illustrate a dentary of P. minor with p1 oriented with the axis of the jaw. As some taxa lack p1 we added a third state, p1 absent. In some Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 14 instances where p1 was single-rooted, its orientation in the dentary could not be well discerned if only alveoli or roots were preserved. 36) First lower premolar: smaller than or subequal to second premolar (0), larger (1), one or both p1 or p2 are absent (2). Ordered. 37) First lower premolar roots: two (0), one (1), p1 absent (2). Ordered. 38) Second lower premolar roots: two (0), one (1), p2 absent (2). Ordered. 39) Third lower premolar size: p2 smaller than or similar in size to p3 and p4 slightly larger than p3 (0), p2 larger than p3 and p4 very much larger than p3 (1), p2, p3, or p4 absent (2). Ordered. Theoretically, p3 could vary in size differently compared to p2 and p4, but for all included taxa they varied the same, hence the combination of these characters. This is modified after character 46 in Rougier et al's. supplementary information (1998). 40) Paraconid on p4 (penultimate premolar): anterior basal cusp absent (0), minute, low anterior basal cusp (1). 41) Metaconid on p4 (penultimate premolar): no metaconid or swelling (0), swelling (1), well developed (2). 42) Heel on p4 (penultimate premolar): single cusp only (0), not-basined, trenchant with a single prominent cusp (1), not-basined, but with two cusps (2). Ordered. 43) Paraconid on p5 (ultimate premolar): minute, low anterior basal cusp (0), small, but distinct anterior cusp (1). Character 47 of Rougier et al.'s supplementary information (1998) deals with the morphology of the ultimate premolar. We have divided this into three characters (43-45). 44) Metaconid on p5 (ultimate premolar): no indication of metaconid or swelling (0), swelling only (1), distinct but small cusp, much smaller than protoconid (2), cusp well-developed, smaller than protoconid but similar in proportions to molar protoconid and metaconid (3). Ordered. It is not clear what the ultimate molariform "premolar" is in Gallolestes (Lillegraven, 1976; Archibald and Averianov, in press), but we utilize Lillegraven's description (1976) of this and the penultimate premolar for characters 43-45. 45) Heel on p5 (ultimate premolar); not-basined, trenchant with a single prominent cusp (0), small-basin or flattened area, sometimes occupying lingual one -half, with a single cusp (1), well-developed, basined talonid (2). Ordered. LOWER MOLARS Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 15 46) Protoconid and metaconid height: protoconid distinctly higher than metaconid (0), cusps of nearly equal height or metaconid somewhat higher (1). This is the same as character 59 of Rougier et al.'s supplementary information (1998). Taxa are coded similarly in both studies. 47) Anteroposterior shortening of trigonid on m1: no shortening with lingual side of trigonid open (paracristid and protocristid form angle of 50 degrees or more) (0), at least some shortening with bases of paraconid and metaconid showing at least some fusion (paracristid and protocristid form angle of 45 degree or less) (1), paracristid very small or absent (2). Ordered. A commonly recognized lower dental character is the amount of compression or closure of the trigonid basin. We attempted to quantify this by measuring the angle created by a line through the apices of the protoconid and paraconid compared to a line through the apices of the protoconid and metaconid. Measurements were taken on published figures or camera lucida drawings of specimens. For m1, the results of these determinations allowed us to divide the taxa with a paracristid into two groups. The measurements are available from the first author. Character 48 of Rougier et al.'s supplementary information (1998) (modified after Cifelli, 1993) deals with "trigonid configuration." Their state assessment was done qualitatively. As indicated, we chose to quantify this character. For m1 we could discern clearly two different groups, which are those identified above as states "0" and "1." 48) Anteroposterior shortening of trigonid on m2: no shortening with lingual side of trigonid open (paracristid and protocristid form angle of 50 degrees or more) (0), at least some shortening with bases of paraconid and metaconid showing at least some fusion (paracristid and protocristid form angle of 35-45 degrees) (1), considerable shortening with bases of paraconid and metaconid with some fusion (paracristid and protocristid form angle 32 degrees or less) (2), paracristid very small or absent (3). Ordered. The procedure outlined under character 47 for m1 was followed for the m2, except that we felt three states were recognizable for m2's with paracristids. The measurements are available from the first author. 49) Anteroposterior constriction or pinching of trigonid at midpoint of para- and protocristid on m1-3: no (0), yes (1). 50) Cristid obliqua: contact closest to middle posterior of metaconid (0), contact closest to lowest point on protocristid (1), contact closest to middle posterior of protoconid (2). Ordered. This pertains to the general expansion of the talonid basin. Although related to the next character (talonid width relative to trigonid width), the two are not tightly correlated. Character 51 of Rougier et al.'s supplementary information (1998) (modified after Cifelli, 1993) also pertains to Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 16 the cristid obliqua and also has three states. Although the state descriptions are slightly different than ours, they appear to code for the same states, which are in agreement for the eutherian taxa in common in the two studies. 51) Trigonid width divided by talonid width on m1 and m2: ratio of 1.10 or greater for m1 and 1.15 or greater for m2 (0), ratio of less than 1.10 for m1 and less than 1.15 for m2 (1). These ratios were for the most part taken from or determined using published sources. The measurements are available from the first author. Character 50 of Rougier et al.'s supplementary information (1998) also pertains to talonid width relative to trigonid width. Their states "1" and "2" are similar to our states "0" and "1," although the codings are not completely equivalent. The only taxon that is coded differently is Kennalestes, with us coding it as more derived. 52) Trigonid height divided by talonid height, measured on labial side of m2 (except m1 for Otlestes): ratio equal to or greater than 2.0 (0), ratio 1.8-1.9 (1), 1.5-1.7 (2), ratio 1.4 or less (3). Ordered. 53) Trigonid height divided by total length of m2 (except m1 for Otlestes): ratio equal to or less than 1.1 (0), ratio 0.9 - 1.0 (1), ratio 0.8 or less (2). Ordered. 54) Relative position of hypoconulid on m1 &2: nearly equidistant between entoconid and hypoconid (0), closer to entoconid than to hypoconid (1). In none of these taxa are the entoconid and hypoconid twinned to the degree seen in metatherians, rather the hypoconid shows some lingual shift probably related to talonid expansion. Character 52 of Rougier et al.'s supplementary information (1998) deals with the position of the hypoconulid. As with a number of other characters, they include more states to encompass a greater range of morphology seen across more therian clades. Thus, hypoconulid/entoconid "twinning" to which they refer clearly pertains to the more exaggerated state seen in metatherians (as noted above) rather than to the smaller lingual shift of the hypoconulid seen in some eutherians, most notably, many zhelestids. DENTARY 55) Labial mandibular foramen: present (0), variably present (1), absent (2) (KielanJaworowska and Dashzeveg, 1989). Ordered. This is character 70 In Rougier et al's. supplementary information (1998). These authors code Otlestes as ancestral for this character. The two dentaries known for this taxon vary, thus the additional state. The same is true for Protungulatum. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 17 56) “Meckelian” groove: present (0), absent (1). This is character 75 in Rougier et al's. supplementary information (1998). They cite Simpson (1928) as the source. 57). “Coronoid” facet: present (0), absent (1). This is character 76 in Rougier et al's. supplementary information (1998). They cite Krebs (1971) as the source. 58) Large anterior mental foramen: variable, below first or second premolars (0), below first and second premolars (1), below first premolar (2), below second premolar (3), no large anterior mental foramen (4). Character 77 in Rougier et al's. supplementary information (1998) dealt with the position of large mental foramina, indicating one is under the second and third premolars and the other is under the first and second molars. The teeth in question should have been identified as the first and second premolars and the fourth and fifth (or penultimate and ultimate) premolars. Further, we recognized the placement of these foramina as two characters, as they frequently did not vary in a concerted manner from one taxon to the next. Two instances of variation are noteworthy. Prokennalestes minor varies in the placement of the anterior mental foramen. In one specimen it is under p1 and in another is under p2 (Sigogneau-Russell et al. 1992). Although not an entirely satisfactory solution, we coded "below first or second premolars (0)" as the ancestral state. One specimen of Paranyctoides aralensis was unusual in having the anterior mental foramen under p3 as well as having double posterior mental foramina, one under p4 and one under p5 (Archibald and Averianov, in press). Such additional foramina found in some taxa were treated as anomalous or they might be autapomorphic for the taxon in question. 59) Large posterior mental foramen: below fourth (penultimate) and fifth (ultimate) premolars (0), below fourth (penultimate) premolar (1), below fifth (ultimate) premolar (2). See character 58 for further discussion. One edentulous dentary (of over 15 zhelestid dentaries), probably of Eoungulatum kudukensis, had the posterior mental foramen under both p4 and p5. SKULL & EAR REGION 60) Shape of snout: with moderate tapering anteriorly (0), with marked narrowing anterior of posterior premolars (1). 61) Premaxillary length divided by maxillary length: less than 0.55 (0), 0.55 to 0.85 (1), and greater than 0.85 (2). Ordered. Lengths are measured along the midpoint between the dorsal most edge and the ventral most edge of the lateral exposure of the premaxilla from the anteriormost edge of the orbit to the anteriormost extent of the premaxilla. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 18 62) Stapedial ratio: rounded, less than 1.8 (0), elliptical, more than 1.8 (1). The five petrosals that we confidently referred to Kulbeckia kulbecke averaged 1.88 (1.52-2.54). The six measurable petrosals that we also confidently referred to zhelestid averaged 1.64 (1.51- 1.68). As noted Wible et al. (2001), Prokennalestes is the only eutherian with a ratio less than 1.8. This also appears to be the case for zhelestids. This is the same as character 127 in Rougier et al.'s supplementary information (1998). 63) Sulcus for stapedial artery: present (0), absent (1). This is the same as character 147 in Rougier et al.'s supplementary information (1998). 64) Prootic canal: present (0), absent (1). In Rougier et al's. supplementary information (1998) they recognized this as their character 124. As they were dealing with a wider range of mammals, they used four states. They noted that Prokennalestes was alone among eutherians in having a short and vertical prootic canal. We have found this is the state in Dzharakuduk zhelestids as well. 65) Crista interfenestralis and caudal tympanic process of petrosal connected by curved ridge: absent (0), present (1). This is character 133 in Rougier et al's. supplementary information (1998). 66) Transpromontorial sulcus for the internal carotid artery: present (0), absent (1). This is character 146 in Rougier et al's. supplementary information (1998). 67) Tympanic aperture of hiatus Fallopii: in roof through petrosal (0), in roof through petrosal or at anterior edge of petrosal (1), at anterior edge of petrosal (2). This is character 123 in Rougier et al's. supplementary information (1998). They did not code this character for Zalambdalestes, but subsequently Wible et al., 2001 coded this as state "1" for this taxon. There is variation in the condition in Kulbeckia; in two specimens the hiatus appears to exit at the anterior edge of the petrosal, in another it may have exited through the roof of the petrosal, and the other two specimens are not well enough preserved for a determination. We coded this variable condition as intermediate (1). The tympanic aperture of hiatus Fallopii is anterior (1) in most archaic ungulates. 68) Lateral flange: restricted to posterolateral corner of promontorium (0), or greatly reduced or absent (1). This is character 126 in Rougier et al's. supplementary information (1998), although they recognized one more character state. 69) Coiling of the cochlea: less than 360º (0), more than 360º (1). This is character 129 in Rougier et al's. supplementary information (1998). McKenna et al.(2000, p. 22) note that "the Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 19 degree of curvature of the cochlear canal in Daulestes cannot be determined with precision, but it seems more curved than that of monotremes and Vincelestes, but less so than in any other known therian mammals." Based upon this we coded Daulestes as ancestral for this character. 70) “Tympanic proccess”: absent (0), present (1). This is character 134 in Rougier et al's. supplementary information (1998). Only one of five Kulbeckia petrosals preserves part of the area in question. There is thickened anteriorly pointing flange of bone that appears to be the lateral half of the "tympanic process." Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 20 Character state changes at nodes Only unambiguous character state changes at the nodes in the accompanying cladogram are listed below. NODE 1 11: 0 > 1. Stylar cusp A (parastyle) from distinct, but smaller than B to subequal to larger than B. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 21 21: 0 > 2. Each internal crista, notably the postparaconular crista from not distinct but forms continuous convex surface with convex or flat conular basin to forms distinct ridge delineating a distinctly concave conular basin. NODE 2 5: 0 > 2. Protocone on P4 (= penultimate premolar) from none or very little to greatly smaller than in P5. 55: 0 > 2. Labial mandibular foramen from present to absent. 56: 0 > 1. “Meckelian” groove from present to absent. 57: 0 > 1. "Coronoid" facet from present to absent. 65: 0 > 1. Crista interfenestralis and caudal tympanic process of petrosal connected by curved ridge from absent to present. 66: 0 > 1. Transpromontorial sulcus for the internal carotid artery from present to absent. NODE 3 1: 1 > 2. Number of upper and lower premolars from 4-5/4-5 to 4/4. 9: 0 > 1. Number of cuspules in the parastylar region from two to one. NODE 4 21: 2 > 1. Each internal crista, notably the postparaconular crista from forms distinct ridge delineating a distinctly concave conular basin to forms distinct wall (winglike) delineating a flat or convex conular basin. 39: 1/2 > 0. Third lower premolar size from p2 larger than p3 and p4 very much larger than p3 or p2, p3, or p4 absent to p2 smaller than or similar in size to p3 and p4 slightly larger than p3. NODE 5 22: 0 > 1. Height of protocone relative to paracone and metacone from protocone distinctly lower to cusps of similar height. 44: 0 > 2/3. Metaconid on p5 (ultimate premolar) from no indication of metaconid or swelling to distinct but small cusp, much smaller than protoconid or cusp well-developed, smaller than protoconid but similar in proportions to molar protoconid and metaconid. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 22 52: 0 > 1. Trigonid height divided by talonid height, measured on labial side of m2 (except m1 for Otlestes) from ratio equal to or greater than 2.0 to ratio 1.8-1.9. NODE 6 8: 0 > 1. Stylar shelf on M1&2 (coded as polymorphic if differs between teeth) from widest point of stylar shelf (centrocrista to greatest labial extent) equal or greater than 29% of total crown width to widest point of stylar shelf (centrocrista to greatest labial extent) from 19% to 27% of total crown width. 17: 0 > 1. Height and size of para- and metacone from paracone higher and larger to cusps of similar height and size. 27: 0 > 1. Pre- and/or postcingula from absent or poorly developed to present but do not reach or extend below the conules. 51: 0 > 1. Trigonid width divided by talonid width on m1 and m2 from ratio of 1.10 or greater for m1 and 1.15 or greater for m2 to ratio of less than 1.10 for m1 and less than 1.15 for m2. 53: 0 > 1. Trigonid height divided by total length of m2 (except m1 for Otlestes) from ratio equal to or less than 1.1 to ratio 0.9-1.0. NODE 7 39: 0 > 1/2. Third lower premolar size from p2 smaller than or similar in size to p3 and p4 slightly larger than p3 to p2 larger than p3 and p4 very much larger than p3 or p2, p3, or p4 absent. 46: 0 > 1. Protoconid and metaconid height from protoconid distinctly higher than metaconid to cusps of nearly equal height or metaconid somewhat higher. 52: 1 > 2. Trigonid height divided by talonid height, measured on labial side of m2 (except m1 for Otlestes) from ratio 1.8-1.9 to ratio 1.5-1.7. NODE 8 16: 0 > 1. Metacingulum from formed only of the postmetaconule crista and terminates dorsal of postmetacrista, which is continuous with the metastylar lobe to formed of the postmetaconule crista continuing on to the metastylar lobe, but posterior margin of metacone sometimes interrupts this connection. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 23 48: 1 > 2. Anteroposterior shortening of trigonid on m2 from at least some shortening with bases of paraconid and metaconid showing at least some fusion (paracristid and protocristid form angle of 35-45 degrees) to considerable shortening with bases of paraconid and metaconid with some fusion (paracristid and protocristid form angle 32 degrees or less). NODE 9 ("Zalambdalestidae" + Glires) 15: 0 > 1. Size and labial extent of metastylar lobe relative to parastylar lobe on M2 from metastylar lobe of similar size and labial extent to metastylar lobe of smaller size and not extended as labially as parastylar lobe. 21: 1 > 2. Each internal crista, notably the postparaconular crista from forms distinct wall (winglike) delineating a flat or convex conular basin to forms distinct ridge delineating a distinctly concave conular basin. 27: 2 > 1. Pre- and/or postcingula from cingula do not reach or extend below the conules to crenulations or linguolabially narrow cingula present. 30: 0 > 1. Lower medial incisor from not with restricted enamel to with restricted enamel. 31: 0 > 1. Enamel extends to near base of root of enlarged lower (and/or upper) incisor from no to yes. 32: 0 > 1. Root of lower medial incisor (i1?) from not extended posteriorly below p1 to extending posteriorly below p1. 33: 0 > 1. Lower medial incisor from root not with large apical opening to root with large apical opening. 36: 0 > 1. First lower premolar from smaller than or subequal to second premolar to larger than or subequal to second premolar. 49: 0 > 1. Anteroposterior constriction or pinching of trigonid at midpoint of para- and protocristid on m1-3 from no to yes. 52: 2 > 3. Trigonid height divided by talonid height, measured on labial side of m2 (except m1 for Otlestes) from ratio 1.5-1.7 to ratio 1.4 or less. 60: 0 > 1. Shape of snout from moderate tapering anteriorly to marked narrowing anterior of posterior premolars. NODE 10 1: 2 > 3. Number of upper and lower premolars from 3-4/4 to 3/4. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 24 11: 1 > 2. Stylar cusp A (parastyle) from subequal to larger than B to very small to indistinct. 32: 1 > 2. Root of lower medial incisor (i1?) from extending posteriorly below p1 to extending posteriorly below p3 or 4. 50: 1 > 2. Cristid obliqua from contact closest to lowest point on protocristid to contact closest to middle posterior of protoconid. 61: 0 > 1. Premaxillary length divided by maxillary length from less than 0.55 to 0.55-0.85. 67: 1 > 2. Tympanic aperture of hiatus Fallopii from in roof through petrosal or at anterior edge of petrosal to at anterior edge of petrosal (2). NODE 11 1: 3 > 5. Number of upper and lower premolars from 3-4/4 to 2-3/1-3. 36: 1 > 2. First lower premolar from larger than second premolar to one or both p1 or p2 are absent. 38: 0 > 2. Second lower premolar roots from two to p2 absent. 58: 2 > 4. Large anterior mental foramen from below first premolar to no large anterior mental foramen. NODE 12 (Glires) 4: 1 > 2. Number of upper canine roots from one to canine absent. 9: 1 > 2. Number of cuspules in the parastylar region from one to none. 10: 0 > 1. Parastylar groove from moderately to well-developed to very reduced or absent. 19: 0 > 2. Distance between paracone or metacone and protocone relative to total anterior or posterior width, respectively from between 45-55% of crown width to less than 45% of crown width. 23: 0 > 1. Amount of antero-posterior expansion of protocone from none to slight. 25: 0 > 1. Shape of molar crown in occlusal view from triangular to trapezoidal. 26: 0 > 3. Constriction of crown through conular region with or without cingulum(a) from no constriction & no cingulum(a) to no constriction & with cingulum(a). 27: 0/1 > 4. Pre- and/or postcingula from usually absent, crenulations or linguolabially narrow cingula present to cingula reach or extend below the conules. 32: 2 > 3. Root of lower medial incisor (i1?) from extending posteriorly below p3 or 4 to extending posteriorly beyond p4. 34: 1 > 2. Number of lower canine roots from one to canine absent. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 25 35: 0 > 2. First lower premolar from oriented in line with jaw axis to p1 absent. 37: 0 > 2. First lower premolar roots from two to p1 absent. 47: 1 > 2. Anteroposterior shortening of trigonid on m1 from at least some shortening with bases of paraconid and metaconid showing at least some fusion (paracristid and protocristid form angle of 45 degree or less) to paracristid very small or absent. 48: 2 > 3. Anteroposterior shortening of trigonid on m2 from considerable shortening with bases of paraconid and metaconid with some fusion (paracristid and protocristid form angle 32 degrees or less) to paracristid very small or absent. NODE 13 (Paranyctoides/Gallolestes clade + "Zhelstidae" + Ungulata) 12: 0 > 2. Stylar cusp C from absent to variably present and if present very small. 23: 0 > 1. Amount of antero-posterior expansion of protocone from none to slight. 25: 0 > 1. Shape of molar crown in occlusal view from triangular to trapezoidal. 27: 2 > 3. Pre- and/or postcingula from cingula do not reach or extend below the conules to cingula variably reach or extend below the conules. 44: 3 > 2. Metaconid on p5 (ultimate premolar) from cusp well-developed, smaller than protoconid but similar in proportions to molar protoconid and metaconid to distinct but small cusp, much smaller than protoconid. 53: 1 > 2. Trigonid height divided by total length of m2 (except m1 for Otlestes) from ratio 0.9-1.0 to ratio 0.8 or less. 65: 1 > 0. Crista interfenestralis and caudal tympanic process of petrosal connected by curved ridge from present to absent. 70: 1 > 0. “Tympanic proccess” from present to absent. NODE 14 1: 2 > 0. Number of upper and lower premolars from 4/4 to 5/5. 5: 2 > 1. Protocone on P4 (= penultimate premolar) from greatly smaller than in P5 to slight swelling. 6: 1 > 0. Roots on P4 (= penultimate premolar) from three roots to two roots. 54: 0 > 1. Relative position of hypoconulid on m1 &2 from nearly equidistant between entoconid and hypoconid to closer to entoconid than to hypoconid. Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 26 NODE 15 (Uzbek zhelestids) 27: 3 > 4. Pre- and/or postcingula from cingula variably reach or extend below the conules to cingula reach or extend below the conules. 35: 0 > 1. First lower premolar from oriented in line with jaw axis to oblique. 41: 0 > 1. Metaconid on p4 (penultimate premolar) from no metaconid or swelling to swelling. 43: 1 > 0. Paraconid on p5 (ultimate premolar) from small, but distinct anterior cusp to minute, low anterior basal cusp. NODE 16 52: 2 > 3. Trigonid height divided by talonid height, measured on labial side of m2 (except m1 for Otlestes) from ratio 1.5-1.7 to ratio 1.4 or less. 53: 2 > 1. Trigonid height divided by total length of m2 (except m1 for Otlestes) from ratio 0.8 or less to ratio 0.9-1.0. NODE 17 23: 1 > 2. Amount of antero-posterior expansion of protocone from slight to moderate. 24: 0 > 1. Amount of labial shift of protoconal apex from none to moderate. NODE 18 23: 2 > 3. Amount of antero-posterior expansion of protocone from moderate to substantial. NODE 19 16: 0 > 1. Metacingulum from formed only of the postmetaconule crista and terminates dorsal of postmetacrista, which is continuous with the metastylar lobe to formed of the postmetaconule crista continuing on to the metastylar lobe, but posterior margin of metacone sometimes interrupts this connection. 23: 1 > 2. Amount of antero-posterior expansion of protocone from slight to moderate. 27: 3 > 4. Pre- and/or postcingula from cingula variably reach or extend below the conules to cingula reach or extend below the conules. 47: 1 > 0. Anteroposterior shortening of trigonid on m1 from at least some shortening with bases of paraconid and metaconid showing at least some fusion (paracristid and protocristid Supplementary Information: LK relatives of rabbits, rodents, & other extant eutherians Archibald et al 27 form angle of 45 degree or less) to no shortening with lingual side of trigonid open (paracristid and protocristid form angle of 50 degrees or more). NODE 20 (Ungulata) 20: 2 > 0. Relative position of paraconule and metaconule on M1-2 from both positioned in nearly same labiolingual plane at midpoint or closer to paracone and metacone to both positioned in nearly same labiolingual plane nearer protocone. 21: 1 > 0. Each internal crista, notably the postparaconular crista from forms distinct wall (winglike) delineating a flat or convex conular basin to not distinct but forms continuous convex surface with convex or flat conular basin. 23: 2 > 3. 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