Paleoclimatic and paleobiological correlation by mammal faunas from Southern America and SW Europe more

Proceedings ofthe 1" R.C.A.N.S. Congress, Lisboa, October 1992 ( Ciéncias da Terra (UNL) Lisboa Nll12 pp. 143-149 4 figs. 1993 Paleoclimatic and paleobiological correlations by mammal faunas from Southern America and SW Europe M.T. AlberdP, F.P. Bonadonna 2, E. Cerdeño 1, G. Leone2, A. LonginellP, J.L. Prado4 , B. Sánchez 1,4 & E.P. Tonni4 Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain. 2 - Dipartimento di Scienze della Terra, UniversítA di Pisa, Italy. 3 - 1st. di Mineralogia e Petrografía, UniversitA di Trieste, ltaly. 4 - Facultad de Ciencias Naturales y Museo de La Plata, CIC, Argentina. ABSTRACT Key words: Correlation; Maromals; Paleoclimatology; Geochemistry; Neogene. The preliminary results of a research dealing with the study of global changes in the last 5 Ma by correlations of continental records between the Northern and the Southern Hemispheres (SW Europe and Argentina, respectively) are reported. The first analyses of the evolutionary patteros point out, in Argentina, two different turnover times: the first one is characterized by a high percentage of marnmal autochthonous ex tinctions placed in the span of time between the last Chapadmalalan and the frrst Ensenadan faunas, around 2.5-2.3 Ma. 1t is possible to identify a high percentage of new immigrant genera from North America in the frrst turnover, while the second one, associated to the "Iast Pleistocene megafaunal extinctions", probably occurred at the beginning of the "Glacial Pleistocene", around 1.0-0.8 Ma. Too oxygen iso tope composition of phosphate from fossil marnmal bones was measured to have a better climatic resolution from faunal elements of two hemispheres and to compare them by results as quantitative as possible. The preliminary efforts are brought out on fourteen deposits from SE Spain. lsotopic and chemical results strongly suggest the existence of a relation between the oxygen isotope composition in various skeletal components and the taphonomic processes of a single deposito The variations of So in the marnmal teeth of Equidae from SE Spain suggest a shift towards a colder environment from the older one, Huélago, to more recent deposits, as well as from Venta Micena to Fuensanta in agreement with the transition from the Middle 10 the Upper Villafranchian, around 2.5 Ma, and the transition between the "Preglacial" 10 the "Glacial" Pleistocene, around 1.9-0.8 Ma. al INTRODUCTION This work reports the preliminary results obtained during the Cirst stage of a cooperation project among Argentina, Italy and Spain, and Cunded by the European Community (E.C. grant n° cn * - CT90 - 0862). The aim ofthe research is the study ofglobal changes by correlations ofcontinental records between the Northem Hemisphere (SW Europe) and the Southem one (Argentina). The goal of the project is to collect climatic information to get a better chronological location of the studied faunas in the last 5 Ma. The work deals with marnmal evolution and incIudes analyses oC oxygen isotopes in phosphate from marnmal bones (Longinelli, 1984). In the Southem Hemisphere we have selected several Atlantic coastal localities between the North oC Mar del Plata and the South oC Miramar (Buenos Aíres province, Argentine, figure la). These localities show the best continental series from the Pliocene to the Pleistocene levels, with a great faunal richness. These faunal assemblages are comprised between the Chapadmalalan Age, Pliocene, and the Pleistocene - Holocene boundary. In the Northem Hemisphere we have used our previous knowledge on the Weste!ll Mediterranean area, mainly the Guadix.BazaBasin,Spain,andthecorrelationswithCentral Italy (Bonadonna & Alberdi, 1987a,b; Alberdi & Bonadonna, 1988, 1989). MATERIAL AND METHODS The mammal assemblages come from the following "Fonnations": Epecuén (Huayquerian age), Monte Hermoso (Montehermosan Age), Chapadmalal 143 Cí2ncias da Terra (UNL), 12 (Chapaumalalan Age), Barranca de Los Lobos. Vorobué and San Andrés ("Uquian" Age), Miramar (Ensenadan age) and Arroyo Seco, Santa Isabel anu Lobería of the Lujanian Age (Tonni el al., 1992; Alberui el al., 1993). The chronological assignement of the stratigraphic scheme showed in Tonniel al. (1992: fig.8) is reviewed according to new data. Conceming the temporal range of the difrerent mamma! ages there are dirferences with respect to the previous geochronologica! scaIe of Marshall el al. (1983, 1984). L- PTA 2 - :3 .4 5, ­ 6,­ 7, ­ 8.- 9.10,- 11- 1213,- . HERMENGO NAUTlCO SCA. PARODI LAS SRUSQUITAS ALAMBRADO ANTENAS AYO, SECO EL MARQUESADO PTA. VOROHUE SUR DE LOS HOTELES HOTEL 6 CHAPADMALAL SANTA ISABEL CRUZ DEL SUR GRIDS MIRAMAR- CHAPADMALAL SECTION 3"- Mjramof 4,- Mor del Ploto Huéscar,J~ 4 1 Baza (;) 5-;.' > GUADIX- BAZA BASI N 1.- CULLAR DE BAZA 1, 2 2.- HUESCAR 1 3.- VENTA MI CENA 4.- CORTES DE BAZA 1 5.- FUENTE NUEVA 1 6.- HUELAGO 7.- BARRANCO CAÑUELAS la 8,- CORTIJO DE TAPIA 9.- LACHAR 10,- FUENSANTA • ~Cullor Baza \ \ MADRID \ G • I \\,\ \ / ~ / ~ ,~ A,me~ío \. ® Fig. 1 - Geographical map of LIle studied areas. A, the Miramar-Chapadmalal Section (Argentina, Southem I1emisphere); B, the Guadix-Baza Basill (SE Spain, Northern lIemisphere). 144 Proceedings of the 1" R.C.A.N.S. Congress, Lisboa, October 1992 In order to represent the Caunal turnover in the Southem Hemisphere, we take the percentage oC flfSt and last records in the Caunistic assemblages (%FR and %LR) Crom the Huayquerian Age LO the Lujanian Age. The %FR and %LR are discriminated between autochthonous and immigrant mammal genera, since through this span oC time, Camilies are scarcely modified and specíes are not taxonomically weU established. RESULTS Results or Faunal Analysis in Southern Hemisphere Two Caunal tumovers are verified: the first one, placed between the Chapadmalalan and "Uquian" Ages, is characterized by a high percentage oC autochthonous extinctioosand oew immigrant genera Crom Nonh America, maioly in the last part oC this time scale (figs. 2 and 3). Duriog the Chapadmalalan Age (assemblage 3) a maximum oC last records occurs. Sorne clades become partially extinct and the Thylacosmilidae, a very specialized carnivorous marsupial Camily, disappear. Most oC these extinctions correspond to Corms whose morphological type is not replaced until the beginning oC the Ensenadan age (assembJage 7), when probably the env ironmental status became once more comparable to the previous period. This is the case Cor the middle sized Olyptodontidae asP lohoplwrusandPlolwplwroides, whose niches are occupied by Sclerocalyptus and Lomaphorus. The largest Olyptodontidae such asEleutherocercus, lastly recorded in the Montehermosan age (assemblage 2), are also repIaced in the Ensenadan. The Chapadmalalan giant Dasypodidae, Macroeuphractus outesi and Macrochorobates chapadmalensis, show a similar pattern, being replaced by Eutatus seguini and Propraopus grandis during the Middle and Late "Uquian" (assemblage 5+6) and the Ensenadan, respectively. Macraucheniidae are represeoted by two genera in the Huayquerian (assemblage 1). One oC them (Macrauchenidia) becomes extinct in the Huayquerian; the other one, Promacrauchenia. persists until Early "Uquian" (assemblage 4). These Corms are repIaced by Macraucheniopsis and Macrauchenia in the Ensenadan and Lujanian, respectively. These and other punctual examples reveal a Caunal tumover only within the autochthonous mammals. It is evident that these changes imply pseudoextinctions or migrations, since sorne lineages disappear Crom one area but they come back in later times. Carnivores have been mentioned as a model oC active replacement oC autochthonous Corms (marsupials) by placental Carnivora Crom the Stratum III (Webb, 1985; Marshall & CiCelli, 1990). Although this necessarily implies the simpatry oC both lineages, this situation is not verified Crom the critical Caunal analysis and new findings. Borhyaenidae is an important camivorous marsupial group which is well diversified during most pan oC the Middle Cenozoic, and becomes extinct in the Montehermosan (last record ofBorhyaenidium,Notocynus, Parahyaenodon and Eutemnodus).. In addition, the last record oC Thylacosmilidae (Thylacosmilus) occurs in the ChapadmaIalan. The active replacement oC these Corms should be performed by placental camivores with similar characteristics as Felidae and, in a lesser degroo, Canidae. However, the f1l'st record oC Felidae happens m the Ensenadan (Berman, 1989; Tonniet al., 1992), and Canldae are flfStly recorded in the Middle-Late "Uquian". The carnivorous role in South America was played also by the mnning birds oC the Camilies Phororhacidae, Psilíopteridae and Brontomithidae (Tonni, 1977; Tonni & Tambussi, 1986). These birds, as well as Thylacosmilidae, have their lastrecord in theChapadmalalan. Phororhacidae participate in the Oreat American Biotic Interchange, and the genus Titanis is coeval with the placental carnivores in North America until Early Pleistocene (Vuilleumier, 1985; Webb, 1991). As Webb (1991) states, this situation - and that shown by the Argentinian record - appears 10 contradict MarshalI's (1977) and Marshall & CiCeHi's (1990) hypotheses, who atribute the extinclion oC "phororhacoids" to the arrival oC holarctie carnivores. The native "ungulates" were also considered as an example oC active replacement by the holarctic ungulates (Webb, 1991). MostoCthe Cormerclades have animportant adaptative radiation during Middle Cenozoic, but they show an abmpt decline in the Chapadmalalan, although most oC them survive. Proterotheriidae reach the ChapadmaIalan with the genus Brachytherium and the Camily still exist in the Pleistocene (Frenguelli, 1921; Alvarez, 1974). Within Toxodontidae, Palaeotoxodon becomes extinct in the Huayquerian, Trigodon and Alitoxodon in the Montehermosan, and Chapadmalodon and Xotodon in the Chapadmalalan. Only one genus, Toxodon, appears in the last Age and still exists in the Lujanian. Hegetotheriidae are represented by five genera Crom the Huayquerian, but only one oC them, Paedotherium, reaches the "Uquian". Webb (1991) suggested that the decrease oC this genus and its final extinction could be due LO the competition with the lamine Camelidae. However, these kinds oC comparisons must be done among taxa with similar size and trophic habits, which is not observed between Paedotherium and any Camelidae. A second turnover (figs. 2 and 3) mcludes the Ensenadan and Lujanian Caunas. It is characterized by a great mcrease oC immigrant genera; there is also an merease oC the autochtonous genera, but they don 't reach again their previous diversity. Amoog the autochthonous Corms, a diversification oC Cingulata (Glyptodontidae and Dasypodídae) and Tardígrada (Scelidotheriinae and Mylodontinae) occurs during that time. Among the immigrantelements, the orders Aniodactyla (Camelidae and Cervidae), Perissodactyla (Equidae), Proboscidea and Carnivora became very díversified. Felidae. Ursidae and the large-sized Canis(Canidae) are firstIy recorded in the Ensenadan. The mammal communities oC this period arecharacterized 145 Ciencias da Tara (UNL) , 12 "lo 60 ®® 5,5 5,0 4,5 4,0 3,5 3,0 2,5 2,0 /' 1 //' /' 2 /3 4 E::j5 l'.t>d6 .7 1,5 Mo Fig. 2 - Graphic representation of faunal evolution in the Chapadmalal sections through time in Ma. The ordinate axis represents the percentage ratio between first occurrence of taxa and the total number of taxa in each assemblage, for autochthonous (1) and immigrants (2), and the percentage ratio between last appearance of taxa and the total number of taxa in each assemblage, for autochthonous (3) and immigrants (4). 5 represents the ratio between appearances and extinctions > 1. 6 represents the ratio between appearances and extintions < l. 7 represents the difference between the first and last appearances of immigrant faunal elements. Encircled numbers: 1 =Huayquerian, 2 = Montehermosan, 3 =Chapadmalal "Fm.", 4 =Bea. Los Lobos "Fm.", 5+6 = Vorohué + San Andrés "Fms.", 7 = Miramar "Fm.", 8 = Luján Fm., 9 = recento MO CH UQ LU R AUTOCHTHONOUS \ 5,5 5,0 4,5 4,0 3,5 3,0 2,5 2,0 1,5 1,0 0,5 o Ma Fig. 3 - Graphic representation of the percentage relation between autochthonous and immigrant faunal elements through time in Ma. HU = Huayquerian, MO=Montehennosan, CH=Chapadmalalan, UQ ="Uquian", EN = Ensenadan, LU = Lujanian, R= Recent. The correlations between the ages (Ma) and the Land Mammal Ages (M=, CH, UQ, EN, LU) are wrong. The correet correlation is in Fig. 2. by the high frequency of megamammals, weighing over 1000 kg (Le.: Toxodon, Megatherium, Lestodon, Doedicurus, Panochthus, Glyptodon, Stegomastodon, Macraucheniopsis). Thís situation is unique, and involves mainly the autochthonous herbivores (except Stegomastodon) whose tendency to giantness reaches its maximal expression in the Ensenadan (Scillato Yanéet al., 1989). All these overweighted species disappear from the South American record in the late Pleistocene-Holocene. In this work, according to the correlation of the global climatic changes between both Hemispheres (Shackleton & Kennett, 1975; Shackleton & Hall, 1984; Haqet al., 1987), we try to correlate these global changes with those succesive faunal turnovers (figs. 2 and 4). In this way, the first turnover which happened during the Chapadmalalan-"Uquian" Ages can be correlated with 146 the cooling which took place around 3.2 - 2.4 Ma. The second one, found during the Ensenadan -Lujanian Ages, occursafter 1.0-0.8 Ma(see figs. 2and3). Thiseventcould be explained as linked to a long sequence of climatic oscillations which are short in time but of great amplitude. Therefore they could be correlated with the beginning of the "Glacial Pleistocene". Another interpretation regarding this second turnover considers it as linked to a climatic improvement followed by a quite long time of stable climatic conditions, in this case the quoted event could be older. Around the Pleistocene-Holocene boundary there is one important extinction involvíng mainly autochthonous mammals (Tonni, 1990). On the other hand, the families of ímmigrant marnmals are well represented in recent faunas, except as concern Equidae and Gomphotheriidae. Proceedings oí (he 1" R.C.A.N.S, Congress, Lisboa, October 1992 Geochemical analysis results Oxygen isotopeanalyseson marnmalshave been perfonned in order to check the application of this methodology on bones of such an old age, and to develop a paleoclimatic interpretation of the results. Theoxygen isotopecompositions of the phosphate from fossil bones coming from fourteen Spanish deposits were measured. These deposits, mainly located in the Guadix­ Baza area, SE Spain, have a good stratigraphical posítion and pennit us a certaín control on the methodology itself, see fig. lb. Results provide evidence of a quite large variability for the samples belongíng to the sarne deposít and also a peculiar feature: theo 1Bo(Pü~ values ofbones are often depleted in heavy isotope with respect to teeth of the same specíes and from the sarne locality. The isotopic difference ranges from a few tenths of one per mil to several o units. In a few cases, narnely Puebla de Valverde, Fuentenueva, Huéscar-l and Cúllar-l deposits, theopposíte behaviour,ó 180(tooth) !!,;ó 180(bone)' takesplaceforalmost a1l the measured specles:Equus stenoniscfr. vireti,Equus stenonisíntennediategranatensis-altidens,Equusaltidens, E. sussenbornensis, Capra sp., Dolichodoryceros savini, Stephanorhinus etruscus. This strongly suggests the existence of a reladon between the oxygen isotope composition, which is now found in the different portions of the skeleton, and the taphonomic processes of a single deposit Mineralogical (XRD) andchemical (XRF)analyses were perfonned on bones of horses belonging to two deposits, Huélago and Cúllar-l. Huélago deposit is the oldest studied one, Middle Villafranchian in age; Cúllar­ 1 is younger, Galerian in age. The results show a major degree of cristallinity of carbonate apatite in bones from the Cúllar-l deposit; moreover, sorne trace elements, Ba and Sr, result to be very enriched in the analysed bone and dentine teeth from Cúllar-l: 3700-3500 versus 1200-1800 ppm for strontium, and 240-350 versus 160-330 ppm for barium. Differences of the same order were also found in Sr by analysing separately enarnel and dentine of the teeth from these two deposits; the Sr and Ba values are about ten times larger than the ones we found in bones of Spanish modero horses. Chemical alteration and oxygen isotope anomalies appear to be distinctive for a single deposit. EQUI DAE EUROPEAN EROSIONAL CONTINEN­ WARM<:l----C>- COLO PHASES TAL STRATI 18 8 O(P04)" INCREASING VALUES GRAPHY CLlMATE MASPINIAN '\.IV' OSTIAN E. caballus ssp. E.sussenbornen­ ' sís E . a Iti'd ens GALERIAN '\.IV' FLAMINIAN '\.IV' CASSIAN U.F FARNETA E. s, granatensis U, F TASSO Cortes de Baza '\.IV' AULLAN E. s, stenonís U.F OLlVOLA E. s. vi reti VERSAN U.F sr VALLlER '\.IV'ACQUATR~I---­ E. s. livenzoven­ sis U. F MONTOPOLl HIPPARION U, F TR IVERSA Fig. 4 - Stratigraphy ofSpanish deposits studied ITom remains ofequids. The curve shows the variations of maximum isotopic values measured in teeth phosphate from each deposit (after Sánchez Ph.D., unpublished). Erosional phases after Ambrosetti et al. (1972). 147 Cihlcias da Terra 12 Al this stage of the research only a very preliminary interpretationoftheoxygen isolOpe results may be attempted fmm a climatic poinl of view. Theo 180 values, mainly in fossil equid 1OOth, fmm the Southeast Spanish area, show differences as large as two 0%0 units when the maximum measured values in each deposit are considered; mean teeth values vary in the same way. Otherwise 0 180 variations in bones do not follow with regularity the trend shown by teeth data. In a paleoclimatic reading of the isolOpic results of these mammal fossil remains, higher 180 content of bones corresponds lO higher average air temperature. Accordingly these data suggesta shortcooling aflertheoldest deposit, Huélago, followed by an apparently markedclimatic impmvemenl which culminates with Venta Micena deposit, where we found the highest isolOpic values, 0 180 18.6 %o vs.SMOW, in anEquus fossil tooth. A new cold stage, Fuensanta deposit, precedes the trend towards a better climate that characterizes the younger studied deposits (see Fig. 4). The biostratigraphy of these deposits (Bonadonna & Alberdi, 1987a,b) shows that Huélago, El Rincón, Barranco deCañuelas-la andCortijo de Tapia belong to theFaunal Unit ofMontopoli which begins just before the first cooling in the Northem Hemisphere and culminates during it; Fuentenueva and Puebla de Valverde belong lO the following Faunal Unil of St. Vallier. This cold event marks the beginning of the same climatic improvement in the Lower Pleistocene we observe in the Venta Micenadeposit; moreover, the 0 180 values obtained in bones from El Rincón seem lO agree with its attribution lO the Faunal Unil of Montopoli previously obtained by studying the 0 180 in freshwater shells and carbonates (Leone, 1985). The reasonable agreement between isotopic and biochronologic data seems lo be encouraging for the development of this kind of study. CONCLUSIONS We can correlate the global climatic changes (ShacklelOn & Kennett, 1975; Shackleton & Hall, 1984; Haqet al., 1987) with the succesive faunistic tumovers verified in Southem South America. The [mt tumover. verified during the Chapadmalalan­ "Uquian" Ages, can be correlated with the cooling around 3.2- 2.4 Ma. The second turno ver occurs specially during the Ensenadan - Lujanian Ages. It can be correlated with the beginning of the "Glacial Pleistocene", around 1.0 - 0.8 Ma. Another explanation would be lO link this second tumover lo a climatic improvement followed by a long period of stable climatic conditions, around 2.0 - 1.5 Ma These tumovers can also be correlated with the similar ones verified in the Westem Mediterranean region (Suc & Zagwijn, 1983; Bonadonna& Alberdi, 1987a,b; Alberdi & Bonadonna, 1988).The Chapadmalalan-UUquian" tumover would correspond to the Huélago deposit in the Northem Hemisphere. Huélago reflects a cold climate, and it is included in the MonlOpoli Faunal Unit, around 2.5 Ma. A faunal tumover occurs between Montopoli and Triversa F.U.; Hipparion is replaced by Equus and Mastodon by Elephas. Therefore, it can be stated than a faunal tumover between 3.5 and 2.5 Ma happened in both Northem and Southem Hemispheres. On the other hand, the second tumover established for the Ensenadan - Lujanian Ages in Argentina can be compared with the Villafranchian - Galerian time span in Westem Europe, represented in the Guadix-Baza area by deposits of Venta Micena, Láchar, Fuensanta, Huéscar-l (Fig 4). In the Northem Hemisphere, aclimatic change and the arrival of a modem fauna occur in this time periodo ACKNOWLEDGEMENTS The drawings were prepared by J. Arroyo at MNCN. The present work was aided by a Research Grant CE Num. en *-CT90-0862, Ihe Spanish Grants DGICYT PB88-0008, and Bilateral Convention CSIC-CONICET. REFERENCES Alberdi, M.T. & Bonadonna, F.P. 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