mosaic evolution in the origin of the hominoidea

Reviewed Article

Folia Primatol 1999;70:125–135

Mosaic Evolution in the Origin of theHominoidea

Todd C. Rae

Evolutionary Anthropology Research Group, Department of Anthropology, University of

Durham, UK, and Department of Mammalogy, American Museum of Natural History,

New York, N.Y., USA

Received: September 15, 1997Accepted after revision: July 14, 1998

Todd C. RaeDepartment of Anthropology, University of Durham43 Old Elvet, Durham, DH1 3HN (UK)Tel. +44 0191 374 7525, Fax +44 0191 374 7527E-Mail [email protected]

ABCFax + 41 61 306 12 34E-Mail [email protected]

© 1999 S. Karger AG, Basel0015–5713/99/0703–0125$17.50/0

Accessible online at:http://BioMedNet.com/karger

Key WordsProconsul W Apes W Hominoid phylogeny W Early Miocene

AbstractThe initial appearance of hominoids, or apes, and the selective pressures that

led to their emergence are currently disputed. Central to the argument are the pro-

consulids, variously described as the earliest apes or as stem catarrhines, based on

facial and postcranial data, respectively. The present paper reports on incon-

gruence and parsimony analyses applied to a combined data set. The results dem-

onstrate that proconsulids are cladistic hominoids, and that the apparent incon-

gruence between the data sets is due to mosaic evolution; the earliest changes in

Hominoidea occurred in the face. These results suggest that the initial divergence of

hominoids involved selection for an ape-like face, and was not driven by an

adaptive shift to below-branch locomotion.

Introduction

The identification of initial members of clades in the fossil record is an important,but difficult, step in understanding the evolution of extant organisms. This is becauseone of the chief aims of phylogenetic analysis is not only to elucidate the pattern ofrelationships between species, but to discern the pattern of evolution in the traits thatcharacterize the taxa in question. Understanding the order of character state changeacross a clade is significant because it provides clues as to which adaptations occurredinitially and, thus, helps explain the divergence between evolutionary groups. This taskis complicated, however, by the fact that early members of a clade are extremely similar

126 Folia Primatol 1999;70:125–135 Rae

to taxa that belong to different clades [1], especially as we move closer to the time ofinitial divergence.

Ideas about the date of the first appearance of the superfamily Hominoidea, or apes(including humans), have varied widely, ranging from the Oligocene to the late Mio-cene, a span of nearly 30 Ma [1–7]. The more ancient dates were championed earlier inthe history of palaeoanthropology, when relatively little was known about Cenozoiccatarrhine evolution. As Pilbeam [8, p. 14] explains:

When the number of taxa was limited, the number of morphological characters small, [and]phylogenetic analysis not rigorous ... there were few impediments to tracing extant lineages well backinto the Neogene, or even earlier.

More recent work, particularly that concentrated on the postcrania [e.g., ref. 9, 10],has emphasized the primitive nature of most fossil ‘apes’ and would support a muchyounger date for the hominoid/cercopithecoid split. Over the last two decades, thedebate over the first appearance of hominoids has focused on the non-bilophodontcatarrhines of the early Miocene of East Africa, or proconsulids. These taxa, ranging insize from 3.5 to 50 kg [7], have been either hailed as ‘the earliest fossil record for theHominoidea’ [11, p. 641], or excluded from the group because the ‘proposed phyleticrelationship between [proconsulids] and extant hominoid primates are [sic] not sup-ported by the evidence’ [5, p. 522]. In addition, it may be that the group is paraphyleticand does not in fact represent an evolutionary clade; some proconsulids may be moreclosely related to extant primate clades than others [12]. Deciding between these alter-native phylogenetic positions for the proconsulids will necessarily elucidate the initialadaptation of the hominoids, and thus allow us to develop hypotheses about theadaptive shift(s) responsible for the original differentiation of apes from monkeys.

Facial EvidencePrevious work by the author [12, 13] tested these alternative catarrhine topologies

by applying parsimony analysis to a previously underutilized (for these taxa) anatomicalarea, the facial skeleton. The results demonstrate that the extant superfamilies Cercopi-thecoidea and Hominoidea are well differentiated by facial synapomorphies, and thatproconsulids share some of these derived characteristics exclusively with extant homi-noids. Four of these characters, outlined below, constitute strong evidence in favour ofplacing proconsulids within the Hominoidea.

The facial skeleton of all extant apes is characterized by the distinctive configura-tion of the premaxillomaxillary suture (PS) and of the nasal bones relative to the medialorbital margin. The primitive condition of the PS, seen in platyrrhines and stem catar-rhine fossils, is for the suture to contact the nasal near the midpoint of the lateral border(fig. 1a). Cercopithecoids share the derived state of the PS contacting the nasal furthersuperiorly, or even contacting the frontal, excluding a nasal-maxillary contact (fig. 1b).In hominoids, the alternative derived condition is found, where the PS contacts thenasal inferiorly or, instead, reaches the margin of the piriform aperture (fig. 1c). (Thiscan rarely be observed in adult extant hominoids, as the PS is obliterated during growth,but is seen clearly in juveniles.) All proconsulids for which the trait can be observeddisplay the hominoid condition.

Hominoids also exhibit a unique configuration of the nasals in the interorbitalregion. Platyrrhines, stem catarrhines, and cercopithecoids all retain nasals that projectanteriorly from the medial margin of the orbits, forming a parabolic arch in transverse

Mosaic Evolution in Apes Folia Primatol 1999;70:125–135 127

Fig. 1. Non-metric facial synapomorphies that indicate hominoid/proconsulid monophyly. Lowerbox: superior projection of the PS. n = Nasal; p = premaxilla; m = maxilla. a Suture contacts nasal nearmidpoint (platyrrhines + stem catarrhines). b Suture contacts nasal (or frontal) superiorly (cercopithe-coids). c Suture contacts nasal inferiorly (hominoids + proconsulids). Upper box: transverse sectionsof the nasals. Anterior is towards the top of the box. The horizontal lines represent the medial marginof the orbits. d Nasals projecting anteriorly (non-hominoids). e Non-projecting nasals (hominoids +proconsulids).

section (fig. 1d). The derived condition seen in hominoids is for the nasals to lie relative-ly flat across the bridge of the nose, with little extension beyond the orbital margins(fig. 1e). Again, all proconsulid faces in which this area is preserved display the homi-noid condition.

The presence of a non-projecting interorbital region in hominoids has been knownfor some time, but its importance as a diagnostic character of apes has not been recog-nized. For example, Gregory [14, p. 66] observed in ‘... the chimpanzee, ... [a] nose flatwith little or no bridge’ compared with the ‘human face ... with its ... protruding nose’.The projecting nasal bridge of modern humans, however, is an evolutionary reversal;early members of the hominid clade (Australopithecus, Paranthropus) display the non-projecting configuration.


Fig. 2. Univariate distributions of metric characters that support a (hominoids + proconsulids) clade.Vertical lines indicate the mean, horizontal boxes are one standard deviation above and below themean. a Naso-alveolar height. Some proconsulids are intermediate between the primitive condition(cercopithecoids + gibbons), and the taller (derived) naso-alveolar clivus (great apes). b Anterior palatewidth. Proconsulids group with the living great ape taxa.

Two additional characteristics link some or all of the early Miocene fossils specieswith extant great apes, to the exclusion of hylobatids. The anterior portion of the palatein great apes and proconsulids is relatively wide, and wider than that seen in hylobatids(fig. 2b). In addition, some proconsulids have a naso-alveolar clivus that is relativelytaller than that seen in gibbons, although not as tall as in chimpanzees or orang-utans(fig. 2a).


Character ConflictAlthough the facial characteristics suggest a close relationship between proconsu-

lids and living hominoids, they do not take into account the evidence of the body belowthe neck. Indeed, most analyses of the proconsulid postcranium suggest an explicitlynon-hominoid bauplan [10, 15–19]. Even those workers who have argued for the pres-ence of some hominoid postcranial synapomorphies in proconsulids [20, 21] haveemphasized the overall primitive catarrhine nature of the proconsulid body [e.g.,19],even to the point of referring to the smaller fossil species as ‘East African primitivecatarrhines’ [17].

To date, however, those parsimony analyses involving postcranial data of procon-sulids [22, 23] have not included cercopithecoids as part of the in-group. These studies,by excluding Old World monkeys from the group analysed, assume that proconsulidsand extant hominoids are related and thus do not explicitly test whether proconsulidsdiverged before or after the ape/monkey split. As a result, we cannot judge from theavailable analyses either (a) if the facial and postcranial data sets are incongruent withone another, or (b) if the combined data support an evolutionary relationship betweenproconsulids and living hominoids. Both of these issues are vital in developing a resis-tant hypothesis of hominoid phylogeny and, thus, elucidating the pattern of characterevolution near the divergence of cercopithecoids and hominoids. The present workapproaches these problems by testing the congruence of the facial and postcranial traits,performing a ‘total evidence’ parsimony analysis of catarrhine phylogeny combiningthese data sets, and outlining the probable pattern of character change near the homi-noid-cercopithecoid split.

Materials and Methods

MaterialsThe in-group consists of five extant species, from the Cercopithecinae (Cercopithecus neglectus)

and Colobinae (Colobus polykomos) within the Cercopithecoidea, and from the Hylobatidae (Hylo-bates lar), Pongidae sensu stricto (Pongo pygmaeus) and African apes (Pan troglodytes) within theHominoidea. The extinct in-group taxa examined include Proconsul africanus (including P. heseloni[24]), P. nyanzae, Turkanapithecus kalakolensis, Afropithecus turkanensis, Dendropithecus macinnesi,and Simiolus enjiessi. Some taxa analysed previously [12] were excluded due to the paucity of post-cranial material available or the difficulty in assigning character states from the literature. The out-group comprises four extant platyrrhines (Cebus, Saimiri, Lagothrix, and Callicebus) and two fossilstem catarrhines (Pliopithecus vindobonensis and Aegyptopithecus zeuxis). Facial data were obtainedfrom the original specimens [13], while the character states for the postcranial traits were gleaned fromthe literature. The data set (see ‘Appendix’) contains only those characteristics that are preserved in atleast one of the early Miocene taxa. The four metric characteristics (1–4) are coded using the homoge-neous subset method of Simon [25].

MethodsTo test whether the two partitions of the data (facial and postcranial, respectively) are congruent,

the data set was subjected to incongruence analysis using the computer program XARN [26]. This testcalculates the difference between the tree length for the entire data set and the length of the topologiesfor the actual partitions of the data, and compares this ‘incongruence length difference’ with a distribu-tion of differences obtained from random allocations of characters to partitions for the same data set[27]. The analysis thus determines whether the difference between the topologies (suggested by differ-ent parts of the body) is significantly larger than that of random divisions of the same data set. If oneset of characteristics (e.g., dental) suggests a phyletic tree that is significantly different from the tree


Fig. 3. Strict consensus cladogram of four equal-ly parsimonious topologies. Tree length 155, RI84.

1

2

Outgroup

Cercopithecus

Colobus

Dendropithecus

Simiolus

P. africanus

P. nyanzae

Afropithecus

Turkanapithecus

Hylobates

Pongo

Pan

3

4

5

6

indicated by another set of data (e.g., biochemical), parsimony analysis of the combined data set willresult in serious character conflict; more data would have to be collected to provide a reasonableestimate of the phylogeny of the organisms.

The outgroup node is reconstructed [see ref. 28] for the facial characters; for the postcrania, theoutgroup condition is taken from the literature which, in most cases, reflects the state found in thestem catarrhines. The resulting data matrix was analysed using the maximum parsimony computerprogram Hennig86 [29]. How well the data support the most parsimonious topologies is measured bythe retention index (RI). This measure of support can be compared between studies [30], as it isindependent of tree length. The more commonly reported consistency index is not suited for inter-study comparison, as this statistic is highly correlated with tree length [31], which is, in turn, depen-dent on the number of characters and taxa, both of which vary between analyses.

Results

Incongruence analysis between facial and postcranial characters using XARNreturned an alpha value of 0.152; alpha !0.05 is required for statistical significance [26].Thus, the null hypothesis of congruence between data sets could not be rejected; thetopologies supported by these partitions of the data are not significantly different fromone another. This congruence between the data sets suggests that a ‘total evidence’approach to phylogenetic analysis will produce a resistant hypothesis of relationships.

The implicit enumeration algorithm (‘ie’) of Hennig86 found four equally parsi-monious trees for the data set, each with a treelength of 155 steps and RI of 84. Thetopologies differ only in the placement of four of the six proconsulids relative to oneanother; the strict consensus cladogram is given in figure 3. The consensus topologyclearly supports the hypothesis that proconsulids are cladistic hominoids. Three of thefour facial synapomorphies previously interpreted as linking the fossil taxa with livingapes were also found to support that phylogenetic placement here; only increased naso-alveolar height is hypothesized to have evolved convergently between proconsulids andthe hominoid crown group. The presence of non-projecting nasals is equivocal at nodes2 and 3, as this area is not preserved in either Dendropithecus or Simiolus, but thederived state is present at nodes 4–6. Also, this topology suggests that the wide anterior


Table 1. Characters and character states

1.2.3.4.5.6.7.8.9.

10.11.12.

FacialNaso-alveolar clivus low (0)–high (6)Piriform aperture narrow (0)–wide (4)Interorbital narrow (0)–wide (6)Anterior palate narrow (0)–wide (6)Incisive foramen (0)/canal (1)Premaxillomaxillary suture low (0)/med. (1)/high (2)Medial alveolus sloping (0)/steep (1)Maxillary sinus mod. (0)/small-abs. (1)Zygomatic root ant. (0)/post. (1)Nasal aperture oval (0)/triangular (1)Nasals project (0)/lie flat (1)Zygomatic vertical (0)/sloping (1)

13.14.15.16.

17.18.

19.20.

21.22.23.24.25.26.27.28.29.

HumeralTrochlea cylinder (0)/trochlear (1)Trochlea med.-lat. broad (1)/narrow (0)Trochlea ant./post. wide (1)/narrow (0)Medial keel:Developed distally and faces distolat. (0)Developed distally and faces lat. (1)Equally developed around trochlea (2)Lateral keel weak (0)/strong (1)Olecranon fossa articular surface limited (0)/consider-able (1)Humeroulnar joint translatory (0)/non-translatory (1)Capitulum:Asymmetrical and not flattened ant./dist. (0)Asymmetrical and flattened ant./dist. (1)Globular or cylindrical (2)Capitulum proximolateral tail present (0)/absent (1)Capitulum 6 trochlea (0)/!trochlea (1)Zona conoidea wide (0)/narrow (1)Zona conoidea shallow (0)/deep (1)Distal articular surface wide (0)/narrow (1)Dorsal epitrochlear fossa present (0)/absent (1)Olecranon fossa shallow (0)/deep (1)Deltoid insertion prox. (0)/dist. (1)Head torsion absent (0)/present (1)

30.31.32.33.

34.35.36.37.38.

UlnarTrochlear notch narrow (0)/wide (1)Olecranon tall (0)/slightly reduced (1)/reduced (2)Median ridge absent (0)/present (1)Lat. surface limited dist./lat. (0)/limited lat. (1)/exten-sive (2)Radial notch orientation ant./lat. (0)/ant. (1)/lat. (2)Radial notch curve even (0)/uneven (1)Shaft bilateral compression strong (0)/weak (1)Styloid-wrist contact present (0)/absent (1)Radial art. restricted (0)/extensive (1)

39.40.41.42.43.44.45.46.

RadialHead fossa small (0)/large (1)Head oval (0)/circular (1)Head surface bevel slight (0)/mod. (1)/marked (2)Head bevel restricted (0)/larger (1)/complete (2)Straight border present (0)/absent (1)Ulnar surface restricted (0)/complete (1)Styloid marked (0)/reduced (1)Shaft short-stout (0)/long-thin (1)

47.48.49.50.51.52.53.54.55.56.57.58.59.60.61.62.63.64.65.

CarpalScaphoid tub. orient. lat. (0)/dist. (1)Scaphoid palmar beak absent (0)/present (1)Scaphoid/lunate joint large (0)/small (1)Central dist. facets angled (0)/flat (1)Lunate and scaphoid facets flat (0)/angled (1)Lunate-radial joint small (0)/large (1)Lunate-capitate joint small (0)/large (1)Triquetral proximal process present (0)/absent (1)Triquetral-ulnar joint restricted (0)/broad (1)/absent (2)Pisiform-ulnar joint med. (0)/prox. (1)/absent (2)Pisiform distal ridge present (0)/absent (1)Trapezium dorsal tub. absent (0)/present (1)Trapezium tubercle small, dorsal (0)/large, lat. (1)Trapezium-MC1 facet orient. dist. (0)/palmarly (1)Trapezoid distal ridge low (0)/high (1)Capitate narrow lat. (0)/expanded (1)Capitate-centrale joint orient. dorso-lat. (0)/lat. (1)Hamate hamulus gracile (0)/robust (1)Hamate spiral facet orient. med.-lat. (0)/prox.-dist. (1)

66.MetacarpalMobile trapezium-MC1 joint absent (0)/present (1)

67.68.69.70.71.72.

FemoralHead cont. with neck (0)/distinct (1)Neck tubercle present (0)/absent (1)Trochanteric fossa post. open (0)/restricted (1)Condyles symmetrical (0)/asymmetrical (1)Shaft vertical (0)/tilted lat. (1)Patellar groove narrow (0)/wide (1)

73.74.75.76.77.78.

TarsalTalus projects lat. mod. (0)/strong (1)Talar trochlea concavity mod. (0)/weak (1)Talar head and neck long (0)/short (1)Talar head narrow (0)/wide (1)Calcaneum narrow (0)/broad (1)Cuboid facet pit present (0)/absent (1)

79.80.81.82.83.84.85.86.87.88.

VertebralRing apophoses absent (0)/present (1)Body keeled (0)/not keeled (1)Trans. processes from body (0)/from pedicles (1)Trans. processes orient. vent.-ceph. (0)/dors.-caud. (1)Neural spine orient. ceph. (0)/caud. (1)Pedicles gracile (0)/robust (1)Anapophoses large (0)/small (1)/absent (2)Lumbar vertebrae number 7 (0)/6 (1)/4–5 (2)Vertebral body long (0)/short (1)Sacral canal narrow (1)/wide (0)

89.90.91.

PelvicIliac blade narrow (0)/wide (1)Iliac angle low (0)/high (1)Iliac tuberosity wide (0)/narrow (1)


palate seen in proconsulids and great apes is an ancestral hominoid characteristic thathas undergone a reversal to the plesiomorphic condition in living hylobatids.

Postcranially (table 1), only one character (76, talar head narrow) is unambiguouslya synapomorphy of the entire (proconsulids + hominoids) grouping, although manycharacters that are unambiguous synapomorphies of a group comprising Proconsul,large Kalodirr taxa and living apes at node 4 (54–58, 65, 66, 83, 85, 86, 88) are equivocalat node 2 because the relevant anatomical structures are not preserved in known speci-mens of Dendropithecus and Simiolus. The latter taxon is linked to the previously men-tioned group (Proconsul + large Kalodirr taxa + living apes) by two more derived charac-teristics (22, capitulum 6 trochlea; 79, ring apophoses absent), one of which (79) is alsoequivocal at the node below.

Two characters of the postcranial skeleton (41, radial head bevel moderate; 42,radial head bevel larger) are present in which the more derived proconsulids (node 4)possess an intermediate condition between the plesiomorphic anthropoid characterstate and the further derived state found in extant hominoids. A further 25 characters(13, 14, 16–18, 20, 21, 23, 24, 27, 39, 40, 43, 54–58, 65, 66, 69, 83, 85, 86, 88) areinterpreted here as synapomorphies of the group in question (Proconsul + large Kalodirrtaxa + living apes), eleven of which may also link all of the fossil taxa examined to livingapes (see above).

These results differ from those obtained only from the facial characters [12, 13] inthat the proconsulids are found here to be stem hominoids, rather than stem great apes,and therefore represent the first appearance of hominoids in the fossil record. Thishypothesis is supported by the high RI; even given a nearly sevenfold increase in thenumber of characters, the RI of the most parsimonious trees in the present study (84) issubstantially higher than the RI of 67 found from parsimony analysis of the facial char-acters alone [12, 13], indicating a better fit between the characters and the topology forthe combined data set.

Discussion

The results of the analyses presented here underline several important aspects inthe study of evolutionary change. First, they demonstrate that incongruence betweencharacter sets may be merely apparent. Even when separate analyses of partitions ofdata result in hypotheses of relationship that are at variance with one another, it is stillpossible that the data support the same tree, as the synapomorphies may be concen-trated in only one or a few anatomical areas due to mosaic evolution. This can be partic-ularly troubling in palaeontological contexts, given the increased probability of recover-ing members of stem groups [sensu ref. 32], which possess some but not all of the diag-nostic traits of the crown group.

Another important conclusion is that the early evolution of hominoids was mosaicin nature. The distribution of character state changes across the combined topologydemonstrates that the evolutionary transition from stem catarrhines to apes wasachieved in a sequential fashion, with some characteristics achieving the derived statebefore others. The discovery of such a sequential pattern of evolutionary change isdependent, here as elsewhere [33], on palaeontology; extinct stem groups provide thebest evidence for the pattern of change near divergence events. Preserved in the fossilrecord of the early Miocene of East Africa are taxa that: (a) are very similar to the


common ancestor of monkeys and apes (Dendropithecus); (b) share a few more derivedcharacters with hominoids (Simiolus), and (c) are substantially closer to modern apes(Proconsul + large Kalodirr taxa). All of these taxa reveal unique combinations of primi-tive and derived character states that are not sampled in extant primates. This is, in fact,the expected pattern of phyletic diversity for a time period near the evolutionary originof a group, and highlights the importance of fossil taxa for reconstructing phylogeneticchange in the evolution of living groups.

The pattern of change hypothesized above also indicates that the initial changesassociated with the emergence of apes were concentrated in the face. Although procon-sulids share some hominoid postcranial synapomorphies, the distinctive characteristicsof the locomotor skeleton in living apes did not arise until after the hominoid faceevolved. This mosaic pattern of evolutionary change, which had been hypothesized pre-viously [16], also suggests that the initial adaptive shift toward hominoids was not pri-marily in locomotor anatomy. Just after the divergence of Old World monkeys andapes, members of the hominoid clade were moving in a way similar to that of the com-mon ancestor, but had already begun to develop an ape-like face. The selective pressuresthat led to the flat interorbital, low PS, and wide anterior palate are unclear at present,although increased incisor size can probably be ruled out for the last of these [12]. Theresults of the present study, however, suggest that, in the original separation of the apelineage, these evolutionary forces were more important than those associated withbelow-branch locomotion.

Acknowledgments

My sincere thanks are extended to J.W. Wanjohi (Office of the President, Kenya), for permissionto study the fossils there, and to those who allowed me access to collections of primates in their care: B.Patterson and W. Stanley (FMNH, Chicago); R. Thorington and L. Gordon (NMNH, Washington,D.C.); P. Andrews (NHM, London); B. Engesser and F. Wiedenmayer (NHM, Basel); M. Leakey andE. Mbutu (KNM, Nairobi); J. Sebedduka and J. Sikkintu (UM, Kampala); E. Simons and P. Chatrath(DPC, Durham, N.C.), and G. Musser, I. Tattersall, J. Brauer (AMNH, New York). I also receiveda great deal of help from the late Wolfgang Fuchs of the AMNH; this paper is dedicated to hismemory.

The research reported here was supported by grants from the National Science Foundation USA(BNS 91119226), the L.S.B. Leakey Foundation, and by the Department of Anthropology, Universityof Durham.


Appendix: Values of Character States in Each Genus

Outgroup24540 20010 0?000 00000 00000 00000 00000 00000 00000 00000 00000 00000 00000 0000000000 00000 00000 00000 0

Cercopithecus20040 31110 00001 10011 00001 10000 00111 00000 00000 00100 00000 00001 00000 0000000000 00000 00000 00000 0

Colobus30620 30100 01001 10011 00001 10000 00111 00000 00000 00100 00000 00001 00000 0000000000 00000 00000 00000 0

Hylobates14550 01010 11110 21112 10110 11111 21220 11111 22111 10001 11112 21100 11111 ?111111111 11111 01111 11110 0

Pongo42061 01011 10110 21112 11110 11111 21220 11111 22111 11011 11112 21110 11111 1111111111 11111 12112 21111 1

Pan43461 01011 10110 21112 11110 11111 21220 11111 22111 11011 11112 21110 11111 1111111111 11111 12112 21111 1

Proconsul africanus2???0 11010 10110 21112 11110 11001 100?0 00011 11100 00000 00011 11100 00001 1001000000 100?0 02?01 ?01?? ?

P. nyanzae12?60 11010 10??? ??1?? ??11? ????? 0???0 ????? ????? ?0000 00011 11100 00001 10010 00?00100?0 01101 10?00 0

Afropithecus32560 110?0 10??? ????? ????? ?1??? ????? ????? ????? ?000? 000?? ??100 ????? 1???? ????0 ???1112112 ????? ?

Turkanapithecus1?56? 11?00 10??? ????? ????? ????0 0??00 ???11 ????1 ????? ????? ????? ????? ????1 ?1??? ????? ?????????? ?

Dendropithecus1??60 11010 ??000 00011 00000 00000 000?0 0??00 0000? ????? ????? ????? ????? ????? ?????100?? ????? ????? ?

Simiolus3???0 1???? ??000 00011 01000 000?? ????? ???00 0000? ????? ????? ????? ????? ?010? ??000 11?11????? ????? ?


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mosaic evolution in the origin of the hominoidea

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