Neandertal Speech

by John Albanese

In the history of human adaptation therehave been several important morphologicalchanges that have had a great influence on humanevolution. One of these morphological changes wasthe reorganization of the upper respiratory tractwhich allowed for the development of language. Inthe past twenty years, much of the research that hasbeen done on the study of hominid vocalization hascentered on the question of Neanderthal speech.The main problem with reconstructing the upperrespiratory tract of hominids is the lack of fossilremains (LaUman et al.. 1979). Most of thestructures involved in vocalization are made of softtissue such as muscle and cartilage and thereforeare not preserved. Several bones, such as the hyoidand the styloid processes, which are key indetermining the morphology of the upper respiratortract, are rarely preserved even in modemskeletons (Arensburg et al., 1990). As a result,researchers have turned to other clues toreconstructing the upper respiratory tract ofNeanderthals. Three lines of evidence have beenpursued: (1) the study of newborn humanmorphology, (2) the study ape morphology, and (3)fossil evidence.

Lieberman, the Hyoid Bone, andReconstruction

One of the first researchers to begin work onNeanderthal speech was Philip Lieberman. In 1971Lieberman along with Cretin published a paper thatdiscussed the speech abilities of Neanderthals. Theyapproached the problem by comparing the crania ofNeanderthals to those of human newborns, humanadults. and apes in order to reconstruct the upperrespiratory tract of Neanderthals. Then using acomputer model. they analyzed the vocal abilitiesof the reconstructed vocal tracts. Lieberman andCretin (1971:204) claimed that "human speech isessentially the product of the source, the larynx forvowels, and a supralaryngeal vocal tract transferfunction". Based on the computer model, they foundthat when compared to newborn and adult humans.Neanderthal vocal abilities resembled humannewborns. Therefore, they concluded thatNeanderthals were incapable of producing the fullrange of modem (adult) human sounds. Liebermanand his colleagues argued that Neanderthals lacked

the anatomy that is essential for producing (1)vowel sounds such as lil. [u], and tal. and (2) nasalversus non-nasal sound. and that the vocal abilitiesof Neanderthals were best suited forcommunication at slow speeds.

Criticism of Lieberman and Crelin's workbegan almost immediately and has not stoppedsince. Most of the criticism has been directed attheir reconstruction of the Neanderthal upperrespiratory tract and not the computer model; if thereconstruction is incorrect then its application inthe computer model is misleading. Mostresearchers agree that the position of the hyoidbone, and therefore the larynx relative to themandible and the cervical vertebrae will determinevocal ability (Houghton. 1993; Arensburg et al.,1990; Laitman, 1985; Falk, 1975; Lieberman andCrelin, 1971). The positioning of the larynx willthen determine the shape of the larynx, the size ofthe oral cavity, and the position of the tongue. Theposition of the Larynx can be estimated bydetermining the position of the hyoid bone. Inhumans the hyoid bone"lies below the body of themandible, and in apes and newborn humans thebody of hyoid lies above the inferior border of themandible (Laitman, 1985; Falk, 1975). Liebermanand Cretin try to show that the position of hyoid inNeanderthals was similar to that of Newborns andapes.

Most of the morphological features inNeanderthals that Lieberman and Crelin describeas "pongid-like" or as similar to newborns havenoilimg to dOwith~posIfi:onOftlie hyoIa- or c-ah·De -interpreted very differently (Arensburg. 1990; Falk,1975). A review of Lieberman and Crelin'sreconstruction shows that there are severalproblems with the newborn model. According toLieberman and Crelin (1971), Neandertal craniaand human newborn crania are similar inappearance if a Neanderthal cranium is reduced tothe size of a human infant's cranium. They claimthat the human infant and Neanderthal skulls aremore elongated from front to back and moreflattened from top to bottom than the adult humancranium and that the squamous portion of thetemporal bone is similar in infant humans andNeandertals. What Lieberman and Crelin fail tomention is how these morphological similaritiesare associated with the ability to speak. The bony

areas that are relevant to the position of the hyoidbone are the styloid processes. the mandible. andthe mastoid processes (Dickson and Maue. 1970;Kahane and Folkins. 1984). Therefore, theflattening and elongation of the cranium has noeffect on vocal abilities as is evident by numerousexamples of culturally modified crania. Thesquamous portion, the styloid process, and themastoid process are all located on the temporalbone. However, this proximity does not necessarilyimply that the squamous portion is also related tovocal ability. Rather. the squamous portion of thetemporal bone is affected by the position of thezygomatic arch. the masseter muscle. and temporalmuscles which are all associated with mastication(du Brul, 1977).

Lieberman and Crelin (1971) go on to statethat the mastoid process is absent in newbornhumans, is absent in chimpanzees. is relativelysmall in gorillas, and is relatively small inNeandertals when compared to adult humans. Theyadmit that there is a great deal of variation in themastoid process of modern humans and that theNeanderthal specimen they used fell within therange of their collection of modern human crania.The mastoid process is the anchor for two muscles:the sternocleidomastoid which attaches with theclavicle and the sternum. and the digastric musclewhich attaches with the hyoid and the mandible(Dickson and Maue. 1970). Therefore. the mastoidprocess can be used as a land mark to determiningthe position of the hyoid bone. However. theprimary function of the mastoid process is ananchor for the sternocleidomastoid muscle whichis a muscle that plays an important role in holdingthe head upright in bipeds. This function of themastoid explains the variation in size inLieberman and Cretin's collection; it explains whynewborns lack a mastoid process (Carlisle andSiegel, 1974); it explains why chimpanzees andgorillas either do not have mastoid processes orhave very small ones (they are not fully bipedal); itexplains why human females can have smallermastoid processes a.."1d speak just as well as humanmales. Furthermore, the size of a the mastoidprocesses can be affected by mechanical stress as isevident in societies were women carry heavy loadson their heads. Therefore, it is logical to concludethat the mastoid process can be fairly important inlocating the position of the hyoid (and therefore thelarynx) but the size of the mastoid process does notseem to be affecting vocal abilities in anysignificant way (Burr, 1976).

Lieberman and Crelin discuss thesimilarities in the mandible of Neandertals andnewborns. They state that both Neandertals andnewborns lack a chin. which they describe as a"pongid characteristic". However. they do not statehow this "pongid characteristic" is related tovocalization. The muscles that attach with the

hyoid and the mandible are the mylohyoid muscle.the geniohyoid muscle, and the digastric muscle(Dickson and Maue, 1970; Kahane and Folkins.1984). These muscles articulate with the mandibleon the posterior and inferior portions of themandible and not the chin. Although the obicularisoris muscle is located in the lip and chin area andplays a role in lip movement and speech, it doesnothing in helping to locate the position of thehyoid or the larynx. Burr (1976:286) states, "thelack of chin [has) no relation to articular speech".The insignificance of the lack of chin invocalization can be demonstrated by simplylooking at the great deal of variation in chin size inmodern humans (Carlisle and Siegel, 1974).Lieberman and Crelin go on and state that thegonial angle in Neandertals and newborns issimilar in inclination, and that the mandibularforamen and mylohyoid grove of both are alsosimilarly angled. Again Lieberman and Crelin donot state how this is significant to vocalization orhow these features relate to the position of thelarynx. Lieberman and Crelin do not give the gonialangle. they simply state that the Neanderthal angleis greater than their human specimens. Therefore.it is impossible to state if the angle found in theNeanderthal mandible is within the range ojhuman variation. There are reasonableexplanations for the large gonial angle and theangle of the mylohyoid grove and the mandibularforamen in the Neanderthal specimen. TheNeanderthal specimen used by Lieberman andCrelin is the cranium from La Chapelle whichsuffered from "prolonged and intensive periodontaldisease" (Carlisle and Siegel, 1974:321). As a result.the individual suffered a great deal of antemortemtooth lose and alveolar resorption which likelycaused the deformation of the mandible and theexaggerated gonial angle (Carlisle and Siegel, 1974).Lieberman and Cretin also state that Neandertalsand newborns have similar mandibular coronoidprocesses and mandibular notches. Lieberman andCretin are vague in their descriptions; they describe

- -the coronoid prccess-as-"broad"-a..'1dthe mnnaibularnotch as "relatively shallow" in newborns andNeandertals. As du Brul (1977) states the broadcoronoid process. the shallow mandibular notch.and the broad mandibular ramus are adaptationsthat allow for a greater force to be exerted on theocclusal surface of the teeth. Houghton (1993), alsostates that these morphological features have noeffect on the oral cavity or the oropharynx becausethe pharynx commences just posterior to thealveolar portion of the mandible; Houghton basesthis statement on the position of thepterygomandibular ligament and mylohyoidmuscle. Therefore, these adaptations inNeandertals are clearly not vocally related (orvocally restrictive).

Lieberman and Crelin attempt to draw

and anterior vector. Falk (1975) states thatLieberman and Crelin have placed the hyoid bonein Neandertals more superiorly than in newbomsand more anteriorly than chimpanzees. Therefore.the hyoid bone has no place to move to whenswallowing.

Houghton (1993) points out another majorflaw in Lieberman and Crelin's (1971)reconstruction. The cervical vertebrae on theLieberman and Crelin reconstruction are notcurved: they show no vertical lordosis. Also.Houghton points out that the Neanderthal craniumhas been incorrectly placed on the Frankfurt planeand therefore the cranium is "looking upwards."When oriented horizontally, the Frankfurt plane is"a reasonable indication of normal human headposture" (Houghton. 1993:139). Houghton (1993:140)states that when the skull is reoriented to alignwith the horizontal Frankfurt plane. "the cervicalspine is given a reasonably human lordosis".Houghton states that essentially the samemorphology of the vertebrae is maintained exceptthat the cervical lordosis requires that theintervertebral discs be incorporated into thereconstruction. These intervertebral discs accountfor a 25% increase in overall length of the cervicalspine and their presence is entirely responsible forthe lordosis. Houghton states that this correction ofthe orientation of the Neanderthal skull will alterthe orientation of the styloid processes and thepterygoid processes so that these processes willresemble human morphology more and willresemble ape and newbom morphology less. Thereare some problems with Houghton'sinterpretations. The cervical lordosis does orientthe styloid processes and the pterygoid processes ina more vertical plane but it does nothing to reorientthese processes with respect the Frankfurt plane:the absolute angle between the styloid processes andthe Frankfurt plane does not change by reorientingthe entire skull. However. Houghton does makeseveral important points regarding the cervicallordosis and the position of the tongue. Lieberman(1989l, t.."iesto shew that a tongue that is humlli"1inshape and size could not possibly fit in thereconstructed oral cavity of Neandertals.Lieberman claimed that if the human tongue wasplaced in the Neanderthal reconstruction, it wouldyield "an impossible creature" With its larynx in itschest. Houghton (1993) suggests that Lieberman hasincorrectly interpreted the landmarks thatdetermine the position of the tongue: the genialtubercles. the mylohyoid line. the length of thepalate. the anterior margin of the mandibularramus. and the distance between the posterioraspect of the mandibular symphysis and theanterior aspect of the cervical column. As a result,Houghton states that Lieberman has positioned thetongue too low in the reconstruction. When theselandmarks are taken into consideration and when

the reconstruction takes into account the cervicallordosis. Houghton is able to place the human-sizedtongue in the reconstruction and still be able toposition the larynx at the four-fifth intervertebraldisc were it is located in modern humans(Arensburg. 1989).

Laitman and Cranial Measurements

The lack of preservation of the styloidprocesses and the hyoid bone has forced researchersto explore other ways of reconstructing the upperrespiratory tract of fossil hominids. In a series ofpapers (e.g. Laitman 1985; Laitman et al .. 1979;Laitman et al .. 1978), Laitmanand colleagues haveexplored how the basicranium of humans. apes. andmonkeys relates to the position of their hyoid bone.the larynx, and the epiglottis. Laitman determinedthe amount of flexion by a series of nine linearmeasurements taken between points on theextemal surface of the base of the skull. Laitmansuggests that a flat or non-flexed basicraniumcorresponds with a larynx that is positioned highin the neck and this pattem was found to exist in allthe mammals Laitman examined except forhumans. In humans. the basicranium was found tobe "markedly" arched or flexed and corresponded toa larynx position low in the neck. Laitman pointsout that this pattem found in humans occurs only"after the early years of life" (1985:284). Laitmanapplied these pattems to the fossil record as a toolin determining the position of the larynx andtherefore the vocal abilities of the fossils. He wastrying to develop a method that could apply to allfossil hominids. but in regards to NeandertalsLaitman et al. (1979:31) write that Neandertals "hadthe potential for greater sound modification thanAustralopithecines. [and] they probably had a morerestricted vocal range than that of modem adult orsubadult humans." However. Laitman takes a lessextreme stance and states.

the first instances of full basicranial flexionsimilar io that of modem humans does notappear until the arrival of Homo sapienssome 300.000 to 400.000 years ago. It mayhave been at this time that hominids withupper respiratory tracts similar to ours firstappeared. (1985:286)

Several researchers have been critical of thebasicranial method. Houghton (1993) questions thevalue of such measurements. He states that thename "basicranial" is misleading since it includespoints such as the prosthion and the staphylionwhich are not considered to be on the cranial base.Instead. Houghton proposes that the cranial baseangle (nasion-ephippion-basion or nasion-sella-basion measured radiologically) be used to comparethe flexion of the base of the skull. When compared

this way Houghton found that the Neanderthalcranial base angle was within modem humanrange. However. Houghton's proposal is as useful asLaitman's since he fails to state how eithermeasurement relates to the position of the hyoid.the larynx. and phonetic capabilities (Arensburg etal .• 1990). Houghton (1993) does uncover otherproblems with Laitman's method. Houghton pointsout that Laitman is using the middle of spheno-OCCipitalsynchondrosis in his measurements andwith the fusion of this Joint this position must beestimated. This problem is further compoundedwhen the base of the cranium is fragmentary.Laitman states that "osteo-metric land marks wereoccasionally missing... and these points werereconstructed... using those landmarks that werepresent".

Other problems with Laitman's basicranialmethod is the classification of crania in age groups.Laitman et al. (1979:16) arbitrarily divided thespecimens that they were working on into five agegroups according to dental eruption:

stage 1: prior to eruption of thedeciduous dentition.

stage 2: from the eruption of the firstcentral incisortoeruption to complete deciduousdentition.

stage 3: eruption of the first permanent molar.stage 4: eruption of the second permanent

molar.stage 5: eruption of the third permanent molar.

Laitman stress that newbom humans agecfrom one and one-half to two years have a larynxthat is positioned high on the neck and that these:infants have upper oropharyngeal morphology thalis similar to apes and monkeys. Yet in the ageclassification of the specimens this critical age ojabout two years old is lumped between the eruptionof the first deciduous incisor and the eruption of thefirst permanent molar which covers the ages frorrabout six months to sLxyears old (Ubelaker. 1992)The Classification of Laitman et al. (1979) of the LaChapelle cranium as having a stage 2 Homo flexiorcan mean that Neandertals could have the vocaabilities of 6 month old infant or a 6 year old childFurthermore. LaUman et al. (1979) state thalseveral specimens such as the Predmost 4. and theCra-Magnon skulls could be assigned to stage :3Homo. stage 4 Homo. or stage 5 Homo. and that theNeanderthal skulls from La Ferrassie. MonteCrrceo. and Saccopastore can be assign to stage 2Homo or stage 3 Homo. This shows two things: thatNeanderthal variation overlaps with Homo sapienvariation and that the classification system used byLaitman et al. is somehow lacking if several craniacan be classified in more than one stage.

Archaeological Evidence: the Kebara CaveHyoid

In 1983, a multidisciplinary team ofresearchers working in Kebara Cave, Israel, madean extraordinary find (Bar-Yosef et al .. 1986). InUnit 12, dated to about 60.000 years BP (Valladas etal., 1987), a well preserved skeleton was found thathad (1)a nearly complete hyoid bone and (2)all thecervical vertebrae in anatomical position. Thecomplete mandible was found with all its teeth, andmost of the post-cranial skeleton was found exceptfor the right leg. The skull was missing except forthe upper right third molar (Bar-Yosefet al., 1986).The hyoid from Kebara was not complete; the distaltip of the left greater hom and the two lesser homswere missing. and the greater homs were not fusedto the body (Arensburg, 1989). However.Arensburg(1989) states that the articular facets for the greaterhoms are very well marked on the lateral bordersof the body. and the ligamentous attachments forthe thyroid cartilage are very clear on the rightgreater homoArensburg also states that the point ofattachment for various muscles such as thegeniohyoid. and omohyoid are visible. In theirstudy Arensburg et al. (1990) compared the hyoidbone from Kebara to a collection of modem hyoidbones. Arensburg et al. (1990) found that "theattachment areas for the infrahyoid muscles on theventral surface of the body [of the hyoid] areidentical to those of modem humans. as are theattachments for the hyoglossus muscles". Theinfrahyoid muscles are (1) the stemohyoids thatattach with the body of hyoid. and with the superiorportion of the manubrium and the medial end of theclavicle. and (2) the omohyoids that attach with thegreater homs of hyoid and with the superior borderof the scapula. The hyoglossus muscle articulateswith the greater hom of the hyoid and supports thestyloglossus muscle and the tongue (Dickson andMaue. 1970). These muscles hold the hyoid and thetongue in an inferior and somewhat posteriorposition in humans (Dickson and Maue. 1970).Arensburg et al. (1990; and Arensburg, 1989) statethat even though the mandible from Kebara ismassive. the size and shape of the hyoid isessentially human and not like the box shapedhyoid found in great apes. Although the craniumwas not preserved, the Kebara hyoid bone. mandibleand complete cervical vertebral column reveal agreat deal about this individual's upper respiratorytract and vocal abilities. Based on the musclemarks. the shape of the hyoid, the size of the hyoidbone. and the hyoid bone's relation to the cervicalvertebrae. this individual likely had his hyoid. and.therefore larynx. in the same position as modemhumans. This evidence supports Houghton's (1993)reconstruction of the Neanderthal upperrespiratory tract.

The near east is a unique area during the

·.!f

Middle Palaeolithic; both Neandertals and Homosapiens were present at the same time. The majorityof the differences between Neandertals and Homosapiens are found in the cranial morphology(Nelson and Jurmain, 1991). Therefore, it is notabsolutely certain if this skeleton from KebaraCave is Neanderthal or not. Arensburg (1989:338)states that the find has implication for the"Mousterian peoples of this site" and he does notexplicitly state that skeleton is Neanderthal.Arensburg et al. (1990) in their study of the hyoidbone from this skeleton were reluctant to explicitlystate that this was Neanderthal, rather they statedthat they were investigating "Middle Palaeolithic"speech abilities. Other researchers are lessambiguous; Bar-Yosef et al. (1986:64), theexcavators of the Kebara skeleton. state "thecharacteristics of the skeleton indicate affinitieswith the Tabun. Amud. and Shanidar [Neanderthal]group rather than with the Qafzeh-Skhul one", andValladas et al. (1987:159), also participants in theexcavation of the site. state "unit XII [at Kebara]yielded a well-organized. almost complete burial ofan adult Neanderthal". Since tWs find is very likelya Neanderthal, Lieberman's reconstruction andLaUman's approach are even less likely. Arensburget al. (1990) addresses the work of both researchers;they state that Lieberman's reconstruction whichplaces the hyoid at the height of the body of themandible and not bellow is not in accordance withthe new find.

Apart from the practical problems withLieberman and Laitman's work. there are severaltheoretical problems. One theoretical problem withthe approach of some researchers is their inabilityto show how the morphology of the upperrespiratory tract is affected by respiration,mastication. and vocalization. All three arefunctions that influence the morphology of thisarea; determining which traits are a result of whichfunction is essential. Another theoretical problemwith Lieberman and others. especially those thatpropose ape models, is that they do not account formorphological variation due to locomotion. Falk(1975:131) states some characteristics of the humanupper respiratory tract such as the separation of theepiglottis from the soft palate are "correlated withthe evolution of erect posture". Laitman discusses insome detail how newboms and other mammals areable to swallow liqUids and breath almostsimultaneously. However. he does not state how themorphology of the basicranium is directly affectedby these functions. Laitman does not present anyevidence that shows that the flexion of thebasicranium is related to vocalization and notmastication. respiration or locomotion. Liebermandoes not address these issues at all; he does not takeinto account that the shape of the Neanderthalmandible may not directly relate with vocalizationbut rather is an adaption to diet or using the mouth

as a tool.There has been a great deal of debate over the

range of vocal abilities of Neandertals. There is noclear evidence that suggests that the upperrespiratory tract of Neandertals was any differentfrom that of modern humans . However, there isevidence that strongly suggests that the morphologyof the Neanderthal upper respiratory tract is withinthe range of variation found in modern (adult)human populations. The ultimate goal of most ofthe researchers is to use the upper respiratory tractreconstructions as another tool in determininghominid phylogeny (LaUman, 1985; LaUman et al ..1979; LaUman et al., 1978, Lieberman and Crelin.1971). Although the ability to speak can not be usedalone to determine how Neandertals are related toother hominids, reconstruction of the upperrespiratory tract is another line of evidence thatcan be pursued while researchers attempt to solvethe "Neanderthal Problem" (Valladas et al .• 1987).Research done by Lieberman, Laitman, and othershas forced physical anthropologist to take a closerlook at what enables humans to communicatethrough spoken language. There are still manyunanswered questions surrounding the upperrespiratory tract of fossil hominids. Arensburg etal. (1990) explicitly state that although the hyoidbone from Kebara strongly suggests that MiddlePalaeo lithic hominids had an essentially modernlarynx, the find is an isolated one. Once the debateover Neanderthal speech is fully resolved, thetechniques that have been used and tested on theNeanderthal case can then be applied to other fossilhominid with a greater degree of confidence.

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