Inferring the diet of fossil mammals is a major approach to mammalian palaeobiology and palaeoecology. Compared to other mammals, proboscideans pose significant problems because elephants eat different kinds of food and may change it frequently. Results obtained by analysing the last molars of Palaeoloxodon antiquus from Neumark Nord, highlight the effectiveness of a multidisciplinary approach in inferring the dietary adaptation of elephants. The microwear pattern and stable isotope data obtained for the straight-tusked elephants from Neumark Nord 1, suggest they were mainly grazers in a wooded grassland and moderately humid environment

Iacumin P.

Palombo M. R.

English

Archivio istituzionale della Ricerca -  Università degli Studi di Parma

     Il Quaternario Italian Journal of Quaternary Sciences 24, (Abstract AIQUA, Roma 02/2011),  Congresso AIQUA Il Quaternario Italiano: conoscenze e prospettive Roma 24 e 25 febbraio 2011 INFERRING THE DIET OF EXTINCT ELEPHANTS: THE CASE STUDY OF STRAIGHT-TUSKED ELE-PHANTS FROM NEUMARK NORD 1 (NORTHEASTERN GERMANY)  Maria Rita Palombo1 & Paola Iacumin2 1Dipartimento di Scienze della Terra, Università “Sapienza”, Roma 2Dipartimento di Scienze della Terra, Università degli studi di Parma. Corresponding author: Maria Rita Palombo <mariarita.palombo@uniroma1.it>   ABSTRACT: Palombo M.R. & Iacumin P., Inferring the diet of extinct elephants: the case study of straight-tusked ele-phants from Neumark Nord 1 (Northeastern Germany). (IT ISSN 0394-3356, 2011)  Inferring the diet of fossil mammals is a major approach to mammalian palaeobiology and palaeoecology. Compared to other mammals, proboscideans pose significant problems because elephants eat different kinds of food and may change it frequently. Results obtained by analysing the last molars of Palaeoloxodon antiquus from Neumark Nord, highlight the effectiveness of a multidisciplinary approach in inferring the dietary adaptation of elephants. The microwear pattern and stable isotope data obtained for the straight-tusked elephants from Neumark Nord 1, suggest they were mainly grazers in a wooded grassland and moderately humid environment.   RIASSUNTO: Palombo M.R. & Iacumin P., Dedurre la dieta degli elefanti fossili: l’esempio di Palaeoloxodon antiquus di Neumark Nord 1 (Germania nordorientale). (IT ISSN 0394-3356, 2011) La definizione della dieta delle specie fossili è uno degli aspetti di maggiore interesse in paleobiologia e paleoecologia. Uno studio che associ l’analisi delle microtracce di usura dentale e degli isotopi stabili è particolarmente utile nel caso degli elefanti fossili, in quanto la definizione delle loro abitudini alimentari pone problemi interpretativi dovuti alla varietà di cibo assunta. Lo studio, applicato agli esemplari di Palaeoloxodon antiquus di Neumark Nord 1, dimostra come questi esemplari vivessero in condizioni climatiche miti e relativamente umide e si cibassero prevalentemente di erbe.   Key words: Microwears, Stable isotope, diet, Palaeoloxodon antiquus, Neumark Nor 1, Pleistocene, Germany.  Parole chiave: Microtracce di usura, Isotopi stabili, dieta, Palaeoloxodon antiquus, Neumark Nord 1, Pleistocene, Germania. 1. INTRODUCTION  Inferring the diet of fossil mammals is a major ap-proach to mammalian palaeobiology and pa-laeoecology. Therefore palaeodiet recon-struction is of increasing interest in depicting environmental changes as well as in investigating a wider range of ecological issues. Since the second half of the last century, two methodological approaches have been developed to supply this information. They are based on microwear enamel defects (produced on tooth enamel by the attrition of food particles), and on stable isotope analyses. Compared to other mammals, elephants pose significant logistical problems for dental microwear analysis (PALOMBO et al., 2005, TODD et al., 2007). Elephants exhibit a quite unusual manner of food comminution, de-pending on the extent of the masticator surface and on the high number of enamel bands of their teeth. Moreover, elephants eat different kinds of food and may change it frequently. As a result, to establish the average dietary adaptation of an ele-phant population, it should be convenient to com-bine microwear with stable isotope analyses. This study is aimed at comparing the results obtained by analysing dental microwears and stable iso-topes in straight-tusked elephants from Neumark Nord 1 (Sachsen-Anhalt; Germany) (PALOMBO et al., 2010), a site which provide an extraordinary palaeontological record, counting about two hun-dreds of flora species, mollusks, insects, and a diversified vertebrate fauna, including fishes, am-phibians, reptiles and several more or less com-plete skeletons of large mammals found in sedi-ments deposited during an interglacial phase (?MIS 7, ? MIS 5e) (MELLER, 2010).   2. MICROWEARS  Analysis, performed on twenty among the best pre-served ultimate e penultimate molars (M2, M3) using both stereomicroscope and scanning elec-tron microscope, reveal a modest variability in the microwear patterns of elephants from Neumark Nord 1. Scratches, especially coarse and hyper-coarse, prevail, though pits, both large and small, maybe locally abundant. Coarse scratches, large and relatively deep, with a U-shaped bottom are usually more frequent in the middle part of enamel band, while fine, sometimes, narrow, deep, and V-shaped scratches have been observed on the bor-der of enamel band. Cross-coarse scratches are always present. Some large and deep cavities (gouges) are also observed. The presence of very small fragments of enamel prisms at the bottom of the cavities suggest the eating of hard food such as wood or bark.  The comparison of the range of variability of num-   155 - 157    155  ber of pits and scratches in extant herbivores high-lights the peculiarity of microwear patterns in ele-phants. The morphospace boundaries were ob-tained by plotting the average numbers of scratches of each dietary category versus the av-erage numbers of pits (Fig. 1). Neumark Nord 1 elephants plot within the so-called meal-by-meal mixed feeders that could change their dietary be-haviour depending on either the most abundant or the most pleasing food, but close to the morpho-space of grazers. In the Principal Component Analysis, extant ele-phants plot close to the fruit dominated browsers, while the fossil elephants from Neumark Nord 1, fall in the overlapping area of fruit-dominated browsers and grazers. This is because the vari-ables that mostly contributed to the setting are the percentage of coarse scratches, large pits and gouges (first component) as well the percentage of cross scratches (second component), not the aver-age number of pits and scratches that, in the bivariate analysis, permits to separate grazers from browsers.  All in all, the microwear pattern of elephants from Neumark Nord 1 suggests they were meal-by-meal mixed feeders, including a large amount of grasses in their diet..  3. STABLE ISOTOPES  Stable isotopes have proved useful in determining the dietary habits of mammals and to obtain infor-mation on past climates and environments (see e.g. DENIRO, 1987; LONGINELLI, 1994; IACUMIN et al., 1996; BOCHERENS, 2003). The δ18O values cal-culated from the Neumark Nord 1 sample, are not statistically different from those already obtained for the Italian elephants from La Polledrara di Ce-Fig. 1, Bivariate plot of the average number of pits versus average number of scratches in extant ungulates (data from SOLOUNIAS & SEMPREBON 2002), extant elephants (Loxodonta africana and Elephas maximus), and Palaeoloxodon antiquus from Neumark Nord 1 (NN). Diagramma di dispersione del numero medio di cavità e strie negli ungulati viventi (dati da SOLOUNIAS & SEMPREBON 2002), negli elefanti viventi L. africana ed E. maximus, e in P. antiquus di Neumark Nord 1 (NN). Fig. 2, Principal component analysis: scatterplot diagram of extant ungulates extant elephants (Loxodonta africana and Elephas maximus) and Palaeloxodon antiquus from Neumark Nord 1 (NN). Variables are average number of pits and scratches, % of large pits, % of gouges, % of fine scratches, % of coarse/hypercoarse scratches, % of mixed scratches, % of cross scratches. Analisi delle component principali effettuata per gli ungulati e gli elefanti (L. africana e E. maximus) attuali e P. antiquus di Neumark Nord 1. Variabili: numero medio di cavità e strie, % di cavità grandi; %di fosse; % di strie sottile; % di strie larghe; di strie “miste”; % di incroci. Fig. 3, Carbon and oxygen isotope values of diet and local meteoric water calculate from the measured carbon and oxygen isotope value of apatite of elephant samples preserved in Neumark Nord 1, and fields of variation of the same parameters of the Italian sites "La Polledrara" and Casal de Pazzi". The symbol represents the mean δ18O value of modern precipitation in the Neumark Nord area (Halle, Leipzig). Dieta e valori delle acque meteoriche calcolate in base ai valori degli isotopi dell’ossigeno e del carbonio ottenuti dall’analisi dell’apatite del campione di Neumark Nord 1. Sono riportati I campi di variabilità ottenuti per I siti italiani di “La Polledrara” e “casal de’ Pazzi): il simbolo indica il valore del δ18O delle precipitazioni moderne nell’area di Neumark Nord (Halle, Lipsia).  M.R. Palombo & P. Iacumin   156   Ms. received: Testo ricevuto il canibbio and Casal de’ Pazzi (PALOMBO et al., 2005). This may suggest that the climate were similar at the two different latitudes during the Mid-dle Pleistocene. However, we have also to con-sider that, unlike the Italian elephants, the German ones are enriched in 18O of about 2‰ in compari-son to the modern precipitation in the Leipzig area. This probably suggests that the mean environ-mental condition were not far from modern ones, slightly warmer at the most.  The nitrogen isotope composition of dentine and bone collagen (δ15Ncoll) are consistent with a diet based mainly on grass which has significantly higher δ15N compared to woody growth forms (VIRGINIA & DELAWICHE, 1982). Accordingly, isotope results suggest that elephants from Neumark Nord were mainly grazers in a wooded grassland and moderately humid environ-ment.   4. REMARKS  Results obtained by analyzing the sample of mo-lars of Palaeoloxodon antiquus from Neumak Nord 1, highlights the effectiveness of a multidisciplinary approach to a large data set in inferring the dietary adaptation of elephants. Elephants, indeed, are known as mega-herbivores showing the highest range of variability in feeding among the extant species. Both Loxodonta and Elephas feed on more than 80 different plant species, eating low grass as well as tree branches or fruits (the latter are eaten especially by the forest species Loxo-donta cyclotis), as well as aquatic vegetation. As a result, the ingested food would vary meal-by-meal, and microwear patterns can change considerably, depending on geographic area, season and also during short time spans. Accordingly, isotope analysis could be a fundamental support in infer-ring the average dietary behaviour of fossil probos-cideans as well as the physic parameters of the environment they inhabited. Among extant ele-phants grazing is generally related to the increase of grass availability during humid periods, whereas browsing increases when grass tend to be with-ered. Accordingly, the patterns in microwear shown by the elephants from Neumark Nord are consistent with the stable isotope data obtained for the site, suggesting temperate and moderately hu-mid environmental conditions.  ACKNOWLEDGEMENTS  We thank Prof. H. Meller for inviting us to study ele-phants from Neumark Nord.   REFERENCES  BOCHERENS H. (2003) - Isotopic biogeochemistry and the paleoecology of mammoth steppe fauna. Advances in mammoth research. Deinsea, 9, 57-76. DENIRO M.J. (1987) -, Stable isotopes and archaeology. American Scientist, 75, 182-191. IACUMIN P., BOCHERENS H., MARIOTTI A. & LONGINELLI A. (1996) - Oxygen isotope analyses of co-existing car-bonate and phosphate in biogenic apatite: a way to monitor diagenetic alteration of bone phosphate? Earth and Planetary Science Letters, 142, 1-6.  LONGINELLI A. (1984) - Oxygen isotopes in mammal bone phosphate: a new tool for paleohydrological and paleoclimatological research? Geochimica et Cosmo-chimica Acta, 48, 385-390. MELLER H. (Ed.) (2010) - Elefantenreich - Eine Fossilwelt in Europa. Landesmuseum für Vorgeschichte, Halle (Saale),  PALOMBO M.R., FILIPPI M.L., IACUMIN P., LONGINELLI A., BARBIERI M. & MARAS A. (2005) - Coupling tooth mi-crowear and stable isotope analyses for palaeodiet reconstruction: the case study of Late Middle Pleisto-cene Elephas (Palaeoloxodon) antiquus teeth from Central Italy (Rome area). Quaternary International, 126–128, 153–170  PALOMBO M.R., ALBAYRAK E. & MARANO F. (2010) - The straight-tusked Elephants from Neumark Nord, a glance to a lost world. In: Meller H. (Ed.) – Elefanten-reich - Eine Fossilwelt in Europa. Landesmuseum für Vorgeschichte, Halle (Saale), 219-247.  SOLOUNIAS N. & SEMPREBON G. (2002) - Advances in the reconstruction of ungulate ecomorphology with appli-cation to early fossils equids. American Museum Novi-tates, 3366, 1–49. TODD N.E., FALCO N., SILVA N. & SANCHEZ C. (2007) - Dental microwear variation in complete molars of Loxodonta africana and Elephas maximus. Quaternary International, 169–170, 192–202.  VIRGINIA R.A. & DELAWICHE C.C. (1982) - Natural 14N abundance of presumed N2-fixing and non-N2 fixing plants from selected ecosystems. Oecologia, 54, 317-325. Inferring the diet of extinct elephants: the case study of ...   January 15, 2011  15 gennaio 2011 

Inferring the diet of extinct elephants: The case study of straight-tusked elephants from Neumark Nord 1 (Northeastern Germany)

Inferring the diet of fossil mammals is a major approach to mammalian palaeobiology and palaeoecology. Compared to other mammals, proboscideans pose significant problems because elephants eat different kinds of food and may changeit frequently. Results obtained by analysing the last molars of Palaeoloxodon antiquus from Neumark Nord, highlight the effectiveness of a multidisciplinary approach in inferring the dietary adaptation of elephants. The microwear pattern and stable isotope data obtained for the straight-tusked elephants from Neumark Nord 1, suggest they were mainly grazers in a wooded grassland and moderately humid environment

PALOMBO, Maria Rita

Archivio della ricerca- Università di Roma La Sapienza

Inferring the diet of extinct elephants: the case study of straight-tusked elephants from Neumark Nord 1 (Northeastern Germany)

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Inferring the diet of extinct elephants: The case study of straight-tusked elephants from Neumark Nord 1 (Northeastern Germany)

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