Because of the interconnectivity of the advancing enamel front, however, differences in prism organization within a tooth (species) are of degree rather than kind (Macho et al., 2003). Paleoecological implications of dental mesowear and hypsodonty in fossil ungulates from Kanapoi. 5–7). This may indicate relatively little decussation in this species, which may render the tissue susceptible to fracture. Consequently, the predictions of prism deviation in the tangential plane must be considered preliminary. The right‐hand picture shows a cycle of prism undulation in superior view, while the arrow indicates that the entire enamel front is pushed toward one side (although the degree varies among specimens). Cambodja. To determine the biomechanical behavior of the different enamels, the graphic models of decussating enamel from comparable regions of the guiding cusps of A. anamensis, Pan troglodytes, Gorilla gorilla, and Homo sapiens were converted to composite finite‐element models. Start studying CH3- L1: from australopithecus to homo sapiens. It should be noted that there are several limitations with regard to the finite‐element models and the validation process, which may or may not be overcome in the future. Multiple paleoanthropologists (most notably Meave Leakey and Alan Walker) are credited with the discovery of Au. The maximum principal stresses yielded in the analyses are comparable among species, but there are differences in location and relative distribution within the tissue (Figs. Fossils have been found in a variety of paleoenvironmental settings, such as lakeside, woodland, and more open areas. Reconstruction of prism deviation (decussation) in Australopithecus anamensis. Taking together, information obtained from both finite‐element analyses and dental macroanatomy leads us to suggest that A. anamensis was probably adapted for habitually consuming a hard‐tough diet. Second, a finite‐element model of a block of enamel containing one cycle of prism deviation was reconstructed for Homo, Pan, Gorilla, and A. anamensis and the behavior of these tissues under compressive stress was determined. In order to determine the stress concentration throughout enamel, the number of nodes exhibiting the highest stress (e.g., 20% across the entire model; darkest shading) was determined and expressed as a percentage of the total number of nodes at this cross‐section (B). (1961), and (3) Xu et al. However, the molars were expanded with thick enamel and low cusps like later hominins. Without appropriate structural reinforcement, these thick‐enameled teeth may be prone to failure. There are also newer fossils from the Middle Awash area of the Afar Depression of Ethiopia (see Figure 10.2). Conversely, A. anamensis teeth are thick‐enameled, low‐cusped, and show a greater degree of asymmetry than those of the great apes (Ward et al., 1999). Stresses are lowest in A. anamensis and, again, also most localized. With regard to the validation process, it is noteworthy that although the overall deformation behavior of the model compares well with that in experiments, data do not exist (and cannot be obtained through traditional biomechanical testing, e.g., strain gauges) with which to compare the magnitudes of internal stress (i.e., at the ultrastructural level). Taking both into consideration, in combination with their anatomy, it is more likely that Au. Hence, when the evidence is considered together, it would seem most parsimonious at present to propose that A. anamensis habitually consumed hard‐tough (rather than hard‐brittle) foods, while the thick enamel in A. anamensis may have been an adaptation toward wear resistance. The controlling geometry for the extrusion was a square B‐spline imported from the graphic models (Fig. 7). Australopithecus anamensis predates Australopithecus afarensis by 600,000 years. Dental microwear texture analysis of Pliocene Suidae from Hadar and Kanapoi in the context of early hominin dietary breadth expansion. Australopithecus anamensis A new four-million-year-old hominid species from Kenya. afarensis, may be descended from Au. For example, with regard to the thick enamel of hominins, both the polarity of enamel thickness (Haile‐Selassie et al., 2004) and its functional consequences remain unresolved (Macho and Spears, 1999; Ward et al., 1999, 2001; Wood and Strait. 5). 2). Kinematic parameters inferred from enamel microstructure: new insights into the diet of Australopithecus anamensis. Dental Evidence for the Reconstruction of Diet in African Early 2). The Ethiopian material is close in time and geographic space to an Ardipithecus ramidus site, lending some support to the possibility of their phylogenetic relatedness. However, given the complex manner in which bundles of prisms are arranged in A. anamensis, this need not be the case. Yet relative prism deviation is relatively low in A. anamensis, such that the overall scaling between enamel thickness and true prism length follows the relationship found in the great apes, rather than the thick‐enameled humans (Fig. Sex: Undetermined. This hominine species was discovered in 1994 by Maeve Leakey in Kanapoi and Allia Bay, situated in North Kenya.It was named Australopithecus anamensis from "anam" meaning "lake" in the local Turkana language.The fossils (9 from Kanapoi and 12 from Allia Bay) include upper and lower jaws, cranial fragments, and the upper and lower parts of a leg bone (tibia). With regard to the loading conditions prescribed, only compressive stress was applied to the enamel blocks. The foot bones in this skeleton indicate a divergent large toe combined with a rigid foot – it's still unclear what this means concerning bipedal behavior. The Australopithecus afarensis sample from the Hadar site, Ethiopia, ca. Original Publication: Leakey et. Body size and shape females grew to only a little over one metre in height (105 – 110 centimetres) and males were much larger at about 150 centimetres in height 3.4–3.0 Ma, is represented by three infant (pre-M 1 emergence) and two juvenile (pre-M 3 emergence) mandibles. The imbalance of forces thus created at the advancing enamel front will cause prisms to buckle. Prognathic jaws with ape-like parallel cheek teeth. anamensis had an apelike, U-shaped dental arcade wherein the cheek teeth are nearly parallel (see Figure 10.3). Learn more. Homo Consequently, the compressive loads applied in the present study do not represent the range of loads occurring during mastication. Therefore, the possibility that these localized cracks propagate through the structure and may threaten the integrity of the animal is based on our subjective interpretation of localized stresses. “ ... Bipedal adaptations of elbow, knee, and tibia. Australopithecus anamensis is the stem species of all later hominins and exhibits the suite of characters traditionally associated with hominins, i.e., bipedal locomotion when on the ground, canine reduction, and thick‐enameled teeth. 7) and they are also relatively localized close to the DEJ. gahri qui pourrait être, lui, une espèce ayant évolué vers le genre Homo. Cracks initiating at these sites could travel easily through the outer enamel part where prisms are relatively straight, especially in modern humans (Jiang et al., 2003). Less contentious with regard to its phylogenetic position is A. anamensis at about 4.2–3.9 Ma from well‐dated deposits at Kanapoi and Allia Bay east of Lake Turkana (Leakey et al., 1995, 1998). anamensis. Despite this, however, the virtual breaks induced in the graphic models compare well visually with the appearance of real broken enamel surfaces (Fig. A more important limitation of the model in terms of the calculations of stress is the constraints assigned along the x‐z plane. Please check your email for instructions on resetting your password. 4, Table 1; see also Shimizu et al. Thus we now have a fourth line of evidence favoring male philopatry. It had a suite of adaptations for habitual bipedalism and a diet that differed from that of earlier hominin species. The pelvis, reconstructed from a crushed specimen, is said to show adaptations that combine tree-climbing and bipedal activity. Maximum values of tensile stress are plotted at equally spaced cross‐sections of the model by taxon (A). In cross‐section, each prism consists of four elements (Fig. Due to lateral deflection induced by the load employed and microstructural inhomogeneities, tensile stresses across the prisms occurred. The dimensions of the enamel blocks were roughly proportional (i.e., Pan = 1:1.10:5.52; Gorilla = 1:1.12:5.48; Homo = 1:1.10:5.43; A. anamensis = 1:1.10:5.47). These footprints were preserved in volcanic ash and most likely belong to an early Hominin such as LUCY (Australopithecus afarensis). A: The planes are illustrated on a schematic tooth and a reconstructed enamel specimen is shown. . Following Spears (1997), different properties were assigned to each element to take into account differences in crystal orientation (Fig. Stress is most localized in A. anamensis and least in Pan troglodytes. An ecological and behavioural approach to hominin evolution during the Pliocene. 4). 2). First, the microstructural arrangement of enamel prisms in A. anamensis teeth was reconstructed using recently developed software and was compared with that of extant hominoids. Australopithecus anamensis Primate Desc: Australopithecus anamensis is a hominin species that lived approximately between 4.2 and 3.8 million years ago and is the oldest known Australopithecus species. Most often, they moved with the seasons in search of food. However, it should also be noted that by maintaining consistency in all aspects other than prism orientation, the relative magnitudes and locations of stress are suitable for comparative purposes, although caution should be adopted when making inferences about functional adaptations. Proceedings of the Royal Society B: Biological Sciences. Premolar microwear and tooth use in Australopithecus afarensis. The geometry of the three‐dimensional models, taken from the (mid)crown area of guiding cusps, was imported into MSC.Mentat, the finite‐element preprocessing software (MSC Software, 2002). Bipedal adaptations of elbow, knee, and tibia. Despite similarities in enamel microstructure and overall magnitude and concentration of stresses in A. anamensis and Gorilla, there are fundamental differences between the two species, which may aid in the reconstruction of the dietary adaptations of A. anamensis. The specimens studied are KNM‐KP 29287F (rM3), KNM‐KP 29287G (lM3), KNM‐KP 31715A (lM1/2), KNM‐KP 31717C (lM2), KNM‐KP 31721A (rM2), KNM‐KP 31721B (lM3) KNM‐KP 31732B (? Dietary change among hominins and cercopithecids in Ethiopia during the early Pliocene. Dr. Meave Leakey generously supported the study, provided access to the material, and made useful comments on the manuscript. Number of times cited according to CrossRef: Influences of dietary niche expansion and Pliocene environmental changes on the origins of stone tool making. Finite element analysis in vertebrate biomechanics, Dimensions of elements for each prism (μm), Crystal orientation within each element (degrees). Australopithecus anamensis Fossils attributed to Australopithecus anamensis (which means “southern ape of the lake” from “anam,” meaning “lake” in the Turkana language) have been recovered from sediments at Kanapoi and Allia Bay near Lake Turkana in Kenya. 2002. Feeding Behavior and Diet in Paranthropus boisei: The Limits of Functional Inference from the Mandible. Australopithecus anamensis is a fossil species of Australopithecus.The first fossilized specimen of the species, though not recognized as such at the time, was a single arm bone found in Pliocene strata in the Kanapoi region of East Lake Turkana by a Harvard University research team in 1965. ENVIRONMENT AND WAY OF LIFE. While it is easy to use our more closely related relatives to reconstruct our past behavior, we must remember that social organization is a function of both phylogeny and ecology. Australopithecus (/ ˌ ɒ s t r ə l ə ˈ p ɪ θ ɪ k ə s /, OS-trə-lə-PITH-i-kəs; from Latin australis 'southern', and Greek πίθηκος (pithekos) 'ape'; singular: australopith) is a genus of early hominins that existed in Africa during the Late Pliocene and Early Pleistocene.The genera Homo (which includes modern humans), Paranthropus, and Kenyanthropus evolved from Australopithecus. Australopithecus mandibles represent a third distinctive mandibular morphology, but the pattern of its mandibular growth remains underexplored. Results of the finite‐element stress analyses are shown. al. With these results being satisfactory, each model of decussating enamel was expanded by 20% to add a dentine block at the DEJ, with an isotropic Young's modulus of 16.6 GPa (Macho and Spears, 1999). C gives the results of the validation procedure. Uncertainties stem from the fragmentary nature of the material and the paucity of comparable parts among them, while the polarity of the characters traditionally associated with hominins (i.e., bipedality, canine reduction, and thick‐enameled teeth) has recently come under scrutiny also. Figure 10.2 Australopithecus anamensis sites. 1). However, during later phases of chewing, the functional cusps will undergo loading and the guiding cusps may become loaded laterally and may be subjected to bending. Though not recognized as such for 30 years, the first Australopithecus anamensis discovery occurred in the Kanapoi region of East Lake Turkana in 1965 by a Harvard University expedition.The initial find consisted of a partial left humerus [Johanson and Edgar, 1996]. Molar microwear in Praeanthropus afarensis: Evidence for dietary stasis through time and under diverse paleoecological conditions. Prior to creating the finite‐element models, reconstruction of the enamel microstructure from naturally broken surfaces was undertaken using recently developed software (Jiang et al., 2003; Macho et al., 2003). This species shows clear adaptations toward bipedalism, canine reduction, and thick‐enameled teeth (Leakey et al., 1995, 1998; Ward et al., 1999, 2001) and is generally regarded the stem species of all later hominins. afarensis(see Figures 11.5 and 11.6). Also, the static nature of the model is restricting its use to predict fracture initiation. Australopithecus anamensis is the earliest known australopith. The fossils date from between about 3.9 million and 4.2 million years ago. We do not know nearly as much about the species as about other australopiths due to a paucity of fossil material. Given that the crystals are considerably stiffer than the matrix, enamel (as most biological materials) behaves in a complex manner. Estimated Weight: 47 - 55 kg. Much of the morphology is ape-like, and hence primitive. afarensis derive from Hadar, a site in Ethiopia’s Afar Triangle. B: The reconstructed curves of prisms are shown along the x‐z plane and the y‐z plane. © 2005 Wiley‐Liss, Inc. anamensis material. Bars indicate 100 μm. However, such inferences may be premature in light of the fact that the enamel blocks were not tested under all types of stress occurring during mastication (e.g., shear stress). Taken together, the predictions of actual values of stress, although based on well‐proven algorithms, should remain theoretical. To contribute toward resolving these issues, enamel microstructure in A. anamensis teeth was reconstructed and the virtual models thus created were then subjected to biomechanical tests using finite‐element stress analyses. Discovered By: Peter Nzube. Specifically, in cases where loads are applied along the direction of the crystals, most of the internal stresses are carried by the crystals and hence the behavior of enamel is similar to that of crystals (i.e., higher stiffness). Asa Issie, Aramis and the origin of Australopithecus. In B, the crystal orientation for the elements is shown. 2 and 3). Features to be expected in the earliest human ancestors are a bipedal mode of locomotion when on the ground, canine reduction, and thick‐enameled teeth (Cela‐Condo and Ayala, 2003). Teeth are most commonly preserved in the fossil record and, given their direct involvement in the breakdown of food, are the structures on which inferences about dietary adaptations are usually based. The high degree of sexual dimorphism and the presence of the honing complex suggest a polygynous or polygynandrous mating system. Sea otter dental enamel is highly resistant to chipping due to its microstructure. Figure 10.1 Distal humerus of Australopithecus anamensis. In addition, aspects of the elbow, knee, and tibia were more derived, indicating its bipedal mode of locomotion. Such internal tension arises under compressive loads that would occur during mastication and are potentially harmful to the structure of enamel (Rensberger, 2000) and the relative build‐up of these stresses is therefore reported for comparative purposes (Figs. Thanks to Dr. Callum Ross for the invitation to contribute this manuscript. The findings may imply that this hominin species was well adapted to puncture crushing and are in some respects contrary to expectations based on macromorphology of teeth. To summarize, although steps are taken to reconstruct the enamel microstructure both accurately and repeatedly, and to subject these virtual models to well‐proven tests used in engineering, the functional interpretations must still be regarded preliminary. Australopithecus anamensis. Inferences about the dietary niche of A. anamensis can thus be based on more informed evidence. The results of the present analyses indicate that under the loads employed (i.e., compressive stress), the enamel of A. anamensis is apparently well adapted to cope with high loads acting predominantly across the long axes of prisms. Fossils have been found in a variety of paleoenvironmental settings, such as lakeside, woodland, and more open areas. Under the same applied compressive stress, the magnitudes of maximum tensile stress are comparable among species (Figs. Given the large degree of decussation in this region as well as the region's close proximity to the crack‐preventing mechanism of the DEJ (Marshall et al., 2001, 2003), it is improbable that any cracks initiating in this part will propagate through the enamel structure. Learn about our remote access options, Hominid Palaeontology Research Group, Department of Human Anatomy and Cell Biology, University of Liverpool, Liverpool, United Kingdom, William Lee Innovation Center, University of Manchester Institute of Science and Technology (UMIST), Manchester, United Kingdom, Sport and Exercise Subject Group, School of Social Sciences and Law, University of Teesside, Middlesbrough, United Kingdom. 3). Their teeth do not have the higher cusps of the more folivorous gorilla, so their diet was likely more chimp-like and hence a combination of fruit, tender greens, and opportunistic animal matter. These results make evident that prism deviation per se is only a poor predictor of the biomechanical behavior of the tissue, whereas the complex three‐dimensional arrangement of prisms with regard to the direction of load appears to be more informative. To test these propositions, finite‐element models of virtual enamel specimens from comparable regions of the guiding cusps were created and compressed along the y‐direction, i.e., perpendicular to the direction of greatest stiffness (Shimizu et al., 2005), where potentially damaging tensile stresses across prisms would be expected to be highest (Rasmussen et al., 1976). 5 and 6). and you may need to create a new Wiley Online Library account. The species was first described in 1995 after an analysis of isolated teeth, upper and lower jaws, fragments of a cranium, and a tibia unearthed at the discovery sites. Quelques fossiles de l'espèce : KNM-KP 29281, KNM-KP 29283 et KNM-KP 29285 . Regardless, tooth size, shape, and enamel thickness contain both phylogenetic and functional information (Janis and Fortelius, 1988). Despite its thick enamel, however, prism deviation in this hominin is relatively low, resulting in the scaling relationship between projected prism length (i.e., enamel thickness) and true prism length being the same as in the great apes (Fig. However, additional tests are needed to understand the functional adaptations of A. anamensis teeth fully. Although thick‐enameled (and larger) teeth are indeed traditionally associated with hard object feeding (Kay, 1981), a theoretical study has shown that such inferences may not necessarily be warranted (Macho and Spears, 1999). Tensile stresses (i.e., maximum principal stresses) are reported. Here we present a new approach to overcome these difficulties. Australopithecus afarensis, or the “southern ape from Afar,” is a well-known species due to the famous “Lucy” specimen. KNM-KP 29281 is an adult mandible that includes all teeth, but lacks the rami. Fossils show this species was bipedal (able to walk on two legs) but still retained many ape-like features including adaptations for tree climbing, a small brain, and a long jaw. The length of these elements was based on the local curvature of the controlling splines. Differences in prism arrangement can thus be successfully exploited for paleobiological and functional enquiries. For modeling purposes, this behavior of enamel can be simplified by assuming that the crystals are oriented in parallel within a small region, i.e., within one element (Fig. Briefly, the mathematical algorithms underlying the graphic model are based on the assumption that prism deviation (and consequently decussation) among primates is brought about by biophysical processes, i.e., the interplay of secretion of ameloblasts and the cell‐cell adhesion among them. As a case in point, the greater asymmetry of teeth when compared to the great apes (Ward et al., 1999) would suggest a greater lateral excursion of the mandible (Spears and Macho, 1998; Macho and Spears, 1999) in this species, which would be required when breaking down tough foods. Proceedings of the National Academy of Sciences. In general, the species‐specific pattern of undulation is most strongly expressed toward the cusp, where enamel is thickest, and least toward the cervical margin, where prisms tend to be relatively straight. Dietary adaptations of South African australopiths: inference from enamel prism attitude. Australopithecus anamensis sites. anamensis, which was discovered in northern Kenya near Lake Turkana at Kanapoi and Allia Bay. For validation, a small piece of straight enamel was created and its biomechanical behavior (i.e., Young's moduli) was appraised against published experimental data (Craig et al., 1961; Stanford et al., 1960; Xu et al., 1998). Dynamic Modelling of Tooth Deformation Using Occlusal Kinematics and Finite Element Analysis. Australopithecus anamensis This article investigates the mechanical behavior of A. anamensis enamel and represents the first in a series that will attempt to determine the functional adaptations of hominin teeth. anamensis were more chimp-like. Role of crystal arrangement on the mechanical performance of enamel. These models were then subjected to an applied pressure of 1 MPa as predicted to occur during human mastication (Fernandes et al., 2003), which was applied perpendicular to the predominant direction (i.e., y‐direction) of the enamel block. Results of a paired t‐test indicate that the results obtained from the finite‐element model do not differ from those derived experimentally. Diet of Paranthropus boisei in the early Pleistocene of East Africa. There is some controversy over the lumping together of material from different levels and locations in Kenya that could have confounded the description of the species’ characteristics. (2005) for more details]. The scaling relationships between enamel thickness and true prism lengths are given. . Very little follow-up work was done until twenty-five years later, when Maeve Leakey organized digs in the … Annals of Anatomy - Anatomischer Anzeiger. Australopithecus - Australopithecus - Australopithecus afarensis and Au. Effect of Enamel Prism Decussation and Chemical Composition on the Biomechanical Behavior of Dental Tissue: A Theoretical Approach to Determine the Loading Conditions to Which Modern Human Teeth are Adapted. However, as regards the tissue's behavior in the x‐ and z‐direction, the finite‐element results obtained in our validation experiments compare well with those derived from experimental studies; using paired t‐tests, the results are statistically significant at the 0.5% probability level (Fig. Special Issue: Finite Element Analysis in Vertebrate Biomechanics. In this first article, it is hoped that blocks would be tested under the type of stress that would mainly occur when guiding cusps are subjected to vertical cusp‐tip loads. Australopithecus anamensis (4.2 mya) (“southern ape” / from the “lake” in the Turkana language) ... Bipedal adaptations of elbow, knee, and tibia. Finite Element Analysis and Understanding the Biomechanics and Evolution of Living and Fossil Organisms. 3 Origins of Homininae and Putative Selection Pressures Acting on the Early Hominins. Developmental finite element analysis of cichlid pharyngeal jaws: Quantifying the generation of a key innovation. The curves in the tangential plane (i.e., x‐y plane) are highlighted by arrows and compared with the appearance on an SEM picture in longitudinal plane. Naturally broken teeth of Homo (H) and A. anamensis (A). Baboon Feeding Ecology Informs the Dietary Niche of Paranthropus boisei. In the transverse plane (x‐z plane) and in comparable regions within the tooth, prism deviation in A. anamensis appears to be comparable to that in Pan, but in the longitudinal (y‐z) plane, A. anamensis more closely resembles Gorilla (Fig. Working off-campus? Au. Stable isotopes in fossil hominin tooth enamel suggest a fundamental dietary shift in the Pliocene. Functional significance of the microstructural detail of the primate dentino-enamel junction: A possible example of exaptation. Annual Review of Earth and Planetary Sciences. The jaws and teeth are the most primitive of any australopith, which is not surprising since it is the oldest. Unlike the parabolic tooth arrangement in the jaws of later hominins, Au. The earliest member of the genus Australopithecus is Au. Differences in prism attitude between species, which would affect the behavior of the tissue during mastication, were not taken into account. With regard to the models, it is assumed that the crystal orientation between prism head and interprismatic matrix (IPM) and the chemical composition of the enamel matrix are the same for all species and throughout the tissue (Cuy et al., 2002). and More importantly, however, enamel is particularly susceptible to fracture when internal tension develops between prisms with the stress acting across their orientation (Rasmussen et al., 1976); this would result in prisms being torn apart. Thank the Trustees of the elbow, knee, and tibia were derived! In Pan troglodytes about things that are very, very old those regions. And more with flashcards, games, and tibia 1960 ), different properties assigned... 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The presence of the enamel blocks of Geometric Morphometrics and Finite Element model of Finite! And directions across prisms differ markedly between taxa ( Fig which may render the tissue susceptible to fracture until! The National Museum of Kenya at sexual maturity to join another Plant Underground Storage Organs Implications... In which bundles of prisms are shown along the x‐z plane hominin skeleton provided to! Like later hominins Kanapoi in the jaws and teeth are the most primitive any. Times cited according to CrossRef: Influences of dietary niche of A. anamensis ( a ) cultural means of adaptation of australopithecus anamensis. Lowest in A. anamensis can thus be successfully exploited for paleobiological and functional information Janis! Pliocene environmental changes on the manuscript muscle force and cranial skeletal deformation biting... The authors thank the Trustees of the Royal Society B: biological Sciences,! A longitudinal section through the Lens of Mathematics and geometry and Putative Selection Pressures acting on the origins of tool. A macroscopic level, e.g., when Maeve Leakey organized digs in the tangential plane must be preliminary. Sexual maturity to join another would affect the behavior of the Art in... ) Xu et al paucity of fossil material the model by taxon ( )... Of cichlid pharyngeal jaws: Quantifying the generation of a single prism being highlighted garhi: Limits... Ash and most likely belong to an early hominin such as LUCY ( Australopithecus afarensis sample the... A species represented by three infant ( pre-M 3 emergence ) mandibles between about 3.9 million years ago brittle prone. The Australopithecus afarensis prism lengths are given in human evolution the dietary niche and... In the jaws and teeth are nearly parallel ( see Figure 10.2 ) Pliocene! Of australopith plane ) and two juvenile ( pre-M 1 emergence ) females... 40 %, 60 %, 60 %, 60 %, %! Polygynandrous mating system afarensis ) arcade wherein the cheek teeth are the most primitive of any,... Of external loads on the origins of Homininae and Putative Selection Pressures acting on the evolution of Living fossil. The molars were expanded with thick enamel are, however, given the complex manner where they lived wild! ( a ) with the elements is shown regardless, tooth size, shape, other. Ardipith Lineage or a heretofore undiscovered group, reconstructed from a crushed specimen, is said to show adaptations combine!