Mammuthus Columbi Research Articles

Dental mesowear analysis of the Columbian mammoth (Mammuthus columbi) from Tultepec, Estado de México, México

The ontogenetic age and dietary preference of 11 individuals of Mammuthus columbi, from the Late Pleistocene sites of Tutlepec I and Tultepec II, Estado de México, were estimated. To accomplish this, their jaws and molars were measured and examined and the dental mesowear of the molars was analyzed. The estimated age (in African Elephant Age) of most individuals studied was less than 30 years, and only a single individual was approximately 45 years old. The average mesowear angle in the molars indicates great variability in their food preferences, finding individuals that are strictly leaf browsers, strictly grazers, on a mixed diet (C3/C4), mostly browsers, and mostly grazers. Additionally, differences in mesowear angle were found between the left and right molars of four individuals who presented anomalies in the position, shape, and depth of the occlusal surface of the molars. The findings in these individuals illustrate the importance of conducting further studies of these paleopathologies and their relationship with the feeding habits of these proboscideans; also, the analysis of dental mesowear should be supplemented with other approaches.

Feeding habits of Columbian mammoths (Mammuthus columbi) from Santa Lucía IV (Late Pleistocene), State of México, México: Stable isotopes analyses

Of the nearly 500 Columbian mammoth remains (Mammuthus columbi) recovered from excavations at Late Pleistocene Santa Lucia Air Force Base Site IV, México, 13 were sampled for carbon and oxygen isotope analyses of dental enamel. The δ13C values indicated that 12 had been C3/C4 mixed feeders, and one had eaten mainly C3 plants. This is similar to data from mammoths from other Santa Lucía localities or other regions of México. Oxygen isotope values were more diverse; these individuals may have lived in different periods during the Late Pleistocene, or the group may represent a mixture of local individuals with others that had come from further afield.

Geoarchaeological Excavations at the Guest Mammoth Site (8MR130), Florida, USA

In 1983, a five-page article was published in The Florida Anthropologist which reported on a submerged mammoth kill site in the Silver River near Ocala, Florida. This claim was supported by evidence consisting of a projectile point, six direct percussion flakes, and “numerous” pressure flakes found in situ with the remains of three Columbian Mammoths. In addition, three of the mammoth bones exhibited what were interpreted as cut-marks. The Guest Mammoth site was the first professional archaeological investigation on an underwater precontact site in the Americas. At the time of discovery, no locality east of the Mississippi River had yielded convincing evidence of human and megafauna interaction. For these reasons and others, the Guest Mammoth site fell into archaeological limbo. The author directed geoarchaeological investigations at the Guest Mammoth site from 2014 to 2019 to assess the standing hypothesis that the site is an intact Late Pleistocene archaeological locality. This paper evaluates the results of the original site excavations and contributes new geoarchaeological data to determine the Guest Mammoth's place in the North American archaeological record. The data presented here do not support the conclusion that the Guest Mammoth site is an unequivocal Late Pleistocene archaeological locality because the mammoth bone and artifact bearing component is not stratigraphically secure and has limited chronological control. However, the presence of datable Late Pleistocene strata and faunal material along with non-diagnostic artifacts indicate that the Silver River is worthy of further geoarchaeological inquiry for Late Pleistocene archaeological sites.

Proboscideans on Parade: A review of the migratory behaviour of elephants, mammoths, and mastodons

The ecology and behaviour of woolly and Columbian mammoths and mastodons have been extensively studied. Despite this, their patterns of mobility, and particularly the question of whether or not they migrated habitually, remains unclear. This paper summarises the current state of knowledge regarding mobility in these species, reviewing comparative datasets from extant elephant populations as well as isotopic data measured directly on the ancient animals themselves.Seasonal migration is not common in modern elephants and varies between years. Nonetheless, non-migratory elephants can still have considerable home ranges, whose size is affected mainly by habitat, seasonal availability of water and food, and biological sex. Strontium isotope analyses of woolly mammoths, Columbian mammoths, and mastodons demonstrate plasticity in their migratory behaviour as well, probably in response to spatio-temporal variations in ecological conditions. However, biological sex is difficult to establish for most proboscidean fossils and its influence on the results of Sr analyses can therefore not be assessed. Advances in intra-tooth sampling and analytical methods for strontium isotope analysis have enabled research on intra-annual movement, revealing nomadic behaviour in all three species. Sulfur isotopes have been analysed from woolly mammoth remains numerous times, but its methodology is not yet developed well enough to inform on past proboscidean mobility in as much detail as strontium studies.The inter- and intra-individual variation in migratory behaviour in mammoths and mastodons implies that their role in the subsistence strategies of Palaeolithic people may have fluctuated as well. Further assessment of hominin-proboscidean predator-prey interactions will require a more detailed understanding of proboscidean habitual mobility in specific contexts and places. Strontium isotope studies based on multi-year enamel sequences from multiple individuals have the potential to provide this insight.

A mathematical model to calculate the population of Mammuthus columbi (Mammalia, Proboscidea, Elephantidae) during the Late Pleistocene in the Valsequillo Basin, Puebla, Mexico

ABSTRACT Mathematical models are a helpful tool that can help palaeoecology research advance in similar ways as the ones already used in theoretical ecology. In this article, we use a mathematical model based on differential equations to estimate the past Mammuthus columbi population in the Valsequillo Basin, Puebla, Mexico. We calibrated the model based on the biological and etiologic parameters of the African elephant Loxodonta africana. In addition to the mean population, the analysis allows inferring the population dynamics of the M. columbi on the Valsequillo Basin. The model is based on the ecological interactions between M. columbi and its food resource. It was found that the population must have been oscillating before an equilibrium was reached. Several potential scenarios based on on-site food production (grass) are here analysed. It was found that a good efficiency of the M. columbi to find food can lead to recurrent cycles of abundance and famine. In this situation, the M. columbi populations must have emigrate and then immigrate in periodic circles to avoid starvation.

Million-year-old DNA sheds light on the genomic history of mammoths.

Temporal genomic data hold great potential for studying evolutionary processes, including speciation. However, sampling across speciation events would in many cases require genomic time series that stretch well into the Early Pleistocene (>1 million years). Although theoretical models suggest that DNA should survive on this timescale1, the oldest genomic data recovered so far is from a 560-780 ka old horse specimen2. Here we report the recovery of genome-wide data from three Early and Middle Pleistocene mammoth specimens, two of which are more than one million years old. We find that two distinct mammoth lineages were present in eastern Siberia during the Early Pleistocene. One of these gave rise to the woolly mammoth, whereas the other represents a previously unrecognised lineage that was ancestral to the first mammoths to colonise North America. Our analyses reveal that the North American Columbian mammoth traces its ancestry to a Middle Pleistocene hybridisation between these two lineages, with roughly equal admixture proportions. Finally, we show that the majority of protein-coding changes associated with cold adaptation in woolly mammoths were present already a million years ago. These findings highlight the potential of deep time palaeogenomics to expand our understanding of speciation and long-term adaptive evolution.

Walking in mud: Remarkable Pleistocene human trackways from White Sands National Park (New Mexico)

Human tracks at White Sands National Park record more than one and a half kilometres of an out- and-return journey and form the longest Late Pleistocene-age double human trackway in the world. An adolescent or small adult female made two trips separated by at least several hours, carrying a young child in at least one direction. Despite giant ground sloth and Columbian Mammoth transecting them between the outbound and return journeys, the human tracks show no changes indicative of predator/prey awareness. In contrast, the giant ground sloth tracks show behaviour consistent with human predator awareness, while mammoth tracks show no such apparent concern. The human footprints are morphologically variable and exhibit left-right asymmetry, which might be due to child carrying. We explore this morphological variability using methods based on the analysis of objective track outlines, which add to the analytical toolkit available for use at other human footprint sites. The sheer number of tracks and their remarkable morphological variability have implications for the reliability of inferences made using much smaller samples as are more common at typical footprint sites. One conclusion is that the number of footprints required to make reliable biometric inferences is greater than often assumed.

Forward and inverse methods for extracting climate and diet information from stable isotope profiles in proboscidean molars

Intratooth stable isotope profiles in enamel provide time series of dietary and environmental information that if correctly interpreted, serve as archives of seasonal variability in past environments. A major challenge in interpreting these profiles arises from time averaging imparted by enamel mineralization and developmental geometry, whereby the primary (δ13C or δ18O) input signal is attenuated and shifted, which can potentially lead to incorrect interpretations of the magnitude or frequency of seasonal variability. Several forward and inverse models have been developed to reconstruct the primary input signal from intratooth profiles in continuously growing teeth. Here the models developed by Passey and Cerling (2002) and Passey et al. (2005) are extended to molars of Elephantinae, which grow over a long but finite interval of time. Proboscidean molars are particularly attractive for intratooth profiles because they may contain a decade or more of information and they are often well preserved in the fossil record because of their thick enamel and large size.Forward model parameters are established using histological analysis of molar thin sections of extant African elephants (Loxodonta africana) and a mammoth (Mammuthus columbi) and by micro-CT analysis of L. africana molar plates. The density of immature enamel is about 65% of the final density of mature enamel. The appositional length varies from approximately 35 to 55 mm, and the maturation length is about 70 mm. Histological methods are used to determine crown formation time (CFT) in elephant and mammoth molar plates. CFT for the elephant and mammoth molar plates studied in thin section are about 5–6 years and 11 years, which translate to mean growth rates of about 21 mm/year and 16 mm/year, respectively.Coeval molar and tusk profiles from a zoo elephant are compared. The tusk isotope profile serves as a proxy for the primary input signal, and thus provides an opportunity to evaluate the forward and inverse models. The results from the zoo elephant profiles demonstrate that the inverse model accurately reconstructs the amplitude and overall structure of the primary input signal. Inverse model results of mammoth molar profiles show double the range of δ13C in measured enamel profiles. Inversion model results illustrate that improved reconstruction of the primary input signal can lead to more accurate interpretations of the seasonal variability of diet and body water and by extension, vegetation and precipitation in past environments.

Mobility studies in fossil mammals from Laguna de las Cruces, San Luis Potosí, México: The strontium isotopic analyses

Strontium isotopic ratios from dental enamel of fossil camels, Camelops hesternus (n=5), horses, Equus sp. (n = 5), and mammoths, Mammuthus columbi (4) from Laguna de las Cruces, San Luis Potosí, central Mexico, have been used to study their migration behavior. Four camels, all horses, and one mammoth display 87Sr/86Sr similar to local plants and soils, thus identified as residents. In contrast, teeth of one camel and two of mammoths show lower 87Sr/86Sr ratios while one mammoth has higher strontium isotopic ratios that indicate that they migrated from other localities. Oxygen isotopes from resident animals are similar, which suggests that those individuals drank water from the same source, whereas δ18O values of migrants are different, confirming the strontium isotopic data findings. However, as yet, it is not possible to determine where the migrants came from because their strontium ratios are different from the plants and soils 87Sr/86Sr values from other Potosian and Zacatecan localities with which they were compared.

Confirming a Cultural Association at the La Prele Mammoth Site (48CO1401), Converse County, Wyoming

Archaeologists have long subjected Clovis megafauna kill/scavenge sites to the highest level of scrutiny. In 1987, a Columbian mammoth (Mammuthus columbi) was found in spatial association with a small artifact assemblage in Converse County, Wyoming. However, due to the small tool assemblage, limited nature of the excavations, and questions about the security of the association between the artifacts and mammoth remains, the site was never included in summaries of human-killed/scavenged megafauna in North America. Here we present the results of four field seasons of new excavations at the La Prele Mammoth site that confirm the presence of an associated cultural occupation based on geologic context, artifact attributes, spatial distributions, protein residue analysis, and lithic microwear analysis. This new work identified a more extensive cultural occupation including the presence of multiple discrete artifact clusters in close proximity to the mammoth bone bed. This study confirms the presence of a second Clovis mammoth kill/scavenge site in Wyoming and shows the value in revisiting proposed terminal Pleistocene kill/scavenge sites.

Enamel isotopes reveal late Pleistocene ecosystem dynamics in southeastern North America

The end of the late Pleistocene (∼10,000 years ago) witnessed the extinction of over seventy percent of North America’s megafaunal genera. Although this pattern has been extensively investigated, its causal mechanisms remain elusive. Much of this difficulty is related to the spatial and temporal discontinuity of sites dating to the period leading up to the extinctions. In this study, we present new stable carbon and oxygen isotope data from Mammuthus columbi and Bison latifrons teeth collected from a well-dated Last Glacial Maximum (∼20,000 rcybp) locality called Clark Quarry in coastal Georgia, USA. This site lies in direct proximity to where Sir Charles Lyell collected the type specimen of M. columbi in 1846 and therefore is of added historical significance. We compare these data to those from similarly aged (Sangamonian interglacial and Wisconsin glacial intervals) localities from Florida and demonstrate the presence of a vegetation gradient with elevated levels of C3 vegetation at higher latitudes. Serially-sampled δ13C and δ18O values suggest that Clark Quarry Mammuthus and Bison changed their diet seasonally with the incorporation of elevated quantities of C4 vegetation during warmer periods. Our data indicate more exaggerated seasonal dietary variability in these taxa at Clark Quarry relative to those collected from the Sangamonian interglacial locality of Waccasassa River in Florida, providing additional evidence for the significant influence of glacial dynamics in structuring North American ecosystems. These high-resolution ecological patterns should be incorporated into hypotheses focused on extinction dynamics in southeastern North America and more broadly.

Home range of the Columbian mammoths (Mammuthus columbi) and grazing herbivores from the Waco Mammoth National Monument, (Texas, USA) based on strontium isotope ratios from tooth enamel bioapatite

Waco Mammoth National Monument (WMNM) is a central Texas, Late Pleistocene fossil site dating to ~67 ka. At least 23 Columbian mammoths (Mammuthus columbi), along with the remains of 12 other vertebrate genera have been discovered at this locality. Mammoth teeth were micro-sampled at a high resolution with a computerized micromill, whereas bison and horse teeth were serially sampled with a handheld rotary tool. Serial samples from these individuals offer insights into the movement patterns (87Sr/86Sr) of WMNM herbivores. Regional vegetation and local sediments were also collected to construct an 87Sr/86Sr isoscape to track past movement of mammals, derived from Sr analyses of teeth enamel. 87Sr/86Sr in WMNM herbivores often reflects multiple grazing provenances, and sources. A series of mixing models are proposed to understand the contribution of different surface Sr sources to herbivore diets. These data indicate one mammoth spent some time at the Llano uplift area ~180 km to the SSW during the formation of molar enamel. The remaining individuals (three mammoths, a bison and a horse) lived in an area more proximal to the WMNM, ≤70 km SE of the site. 87Sr/86Sr from WMNM mammoths indicate individual fidelity to at least two geographic ranges, with at least one mammoth, potentially unrelated to the possible matriarchal herd, indicating complex population dynamics prior to mass mortality. This analysis shows that at least 25 mammals, including the horse and bison, congregated at the confluence of Brazos and Bosque rivers at ~67 ka ago, prior to their demise. A resource shortage related to drought is consistent with this pattern.

Feeding traits and dietary variation in Pleistocene proboscideans: A tooth microwear review

Microwear data were analysed to study dietary traits in Elephantidae, Mammutidae, and Gomphotheriidae from Plio-Pleistocene localities from Europe and North America and included the following taxa: Palaeoloxodon antiquus, Mammuthus rumanus, M. meridionalis, M. trogontherii, M. primigenius, M. columbi, Mammut americanum, and Anancus arvernensis. Mammuthus shows a wide variety of dietary strategies, with an overall trend from browsing to grazing through the lineage from M. rumanus to M. primigenius. Nonetheless there is significant inter-population variability which is clearly related to the resources available or to limitations imposed by competition and niche partitioning with other large herbivores. Among the species, Mammuthus columbi (Late Pleistocene of North America) displays both browsing and grazing populations and individuals and also shows heavier pitting than the other species of Mammuthus studied, possibly indicating the occupation of a more arid habitat. The Middle and Late Pleistocene Palaeoloxodon antiquus from Europe also shows dietary plasticity, with browsing, grazing and mixed feeding patterns observed. Dietary variability appears to be lower in Mammut americanum from North America and Anancus arvernensis which were apparently committed browsers (except the grass-dominated mixed feeding A. arvernensis from Norwich Crag). Our results reveal interesting patterns involving Pleistocene vegetation structure and climate as well as aspects of niche utilization.

Distribución de Mammuthus columbi (Mammalia, Proboscidea) en el Pleistoceno tardío de Puebla, México

Se hace un recuento de las localidades con restos de Mammuthus columbi en Puebla. Los resultados arrojan 32 localidades previamente reportadas y seis nuevas, lo cual representa 14% del total de las que se habían reportado para México, y ubican a Puebla como el segundo estado con más restos detrás del Estado de México. Por otro lado, la distribución de las localidades corresponde con el corredor biogeográfico Eje Neovolcánico Transversal-Sierra Madre del Sur. La amplia distribución de restos de Mammuthus columbi demuestra el potencial con el que cuenta el estado y da un punto de partida para futuras exploraciones en pro de ampliar el conocimiento sobre el pasado de México.

Soft-sediment deformation below mammoth tracks at White Sands National Monument (New Mexico) with implications for biomechanical inferences from tracks

Implicit in any biomechanical analysis of tracks (footprints), whatever the animal, is the assumption that depth distribution within the track reflects the applied plantar pressure in some way. Here we describe sub-track deformation structures produced by Proboscidea (probably Mammuthus columbi) at White Sands National Monument (WHSA) in New Mexico. Patterns of sub-surface deformation are consistent with the plantar pressure data for modern Proboscidea, but do not reflect track morphology. Our work cautions against overinterpreting track topology of any large animal, including extinct animals such as sauropods, in terms of their biomechanics unless the subsurface stratigraphy and associated variation in shear strength is known.

A comprehensive genomic history of extinct and living elephants

Elephantids are the world's most iconic megafaunal family, yet there is no comprehensive genomic assessment of their relationships. We report a total of 14 genomes, including 2 from the American mastodon, which is an extinct elephantid relative, and 12 spanning all three extant and three extinct elephantid species including an ∼120,000-y-old straight-tusked elephant, a Columbian mammoth, and woolly mammoths. Earlier genetic studies modeled elephantid evolution via simple bifurcating trees, but here we show that interspecies hybridization has been a recurrent feature of elephantid evolution. We found that the genetic makeup of the straight-tusked elephant, previously placed as a sister group to African forest elephants based on lower coverage data, in fact comprises three major components. Most of the straight-tusked elephant's ancestry derives from a lineage related to the ancestor of African elephants while its remaining ancestry consists of a large contribution from a lineage related to forest elephants and another related to mammoths. Columbian and woolly mammoths also showed evidence of interbreeding, likely following a latitudinal cline across North America. While hybridization events have shaped elephantid history in profound ways, isolation also appears to have played an important role. Our data reveal nearly complete isolation between the ancestors of the African forest and savanna elephants for ∼500,000 y, providing compelling justification for the conservation of forest and savanna elephants as separate species.

Late Pleistocene mammoth trackway from Fossil Lake, Oregon

Behavior of Columbian mammoths (Mammuthus columbi) is revealed by a newly discovered trackway at the Pleistocene locality of Fossil Lake, Oregon. Our 8 by 20 m excavation of the mammoth trackway found 117 tracks, including one 20-m-long adult trail, partial trackways of 3 additional adults, a yearling and a baby all heading generally west. The tracks are in the Marble Bluff biotite tuff (43.2 cal ka), which forms a surface horizon to the Pogani silty clay loam paleosol (Natrargid), with a cracked surface and a columnar-structured, subsurface (Bn) horizon, like soils under desert soda pans with alkali shrubland. Directly below is the Yada silty clay paleosol (Xeroll) with crumb textured surface (A) horizon like grassland soils. The Pasiwa loam (Psamment) is a thin brown siltstone, with sparse roots and burrows of lake-margin early successional vegetation. The Pui sandy loam (Aquent) is well-bedded tuff and sand (A) with subhorizontal calcareous rhizomes and adventitious roots, like those of lake-margin tule reeds (Schoenoplectus acutus). Columbian mammoths may have moved like modern elephants with infants in matriarchal groups through landscapes of sagebrush and grassland, and this trackway includes a limping female attended by concerned juveniles. Grassland paleosols common in the Fossil Lake Formation, are now rare in the same region, perhaps related to extinction of proboscidean and equine grazers.

Dietary ecology of Pleistocene mammoths and mastodons as inferred from dental microwear textures

The Columbian mammoth (Mammuthus columbi) and the American mastodon (Mammut americanum) have traditionally been considered to have been ecologically distinct, with mammoths often characterized as cosmopolitan grazers or mixed feeders and mastodons as forest-dwelling browsers. However, these large-bodied proboscideans occupying temperate, often resource-limiting environments in Pleistocene North American would have necessitated a much wider range of resources. For the isolated pygmy mammoth (Mammuthus exilis) of California's Channel Islands, the resource-limited nature of its insular home may have exacerbated the need for consumption of a wide range of less-preferred resources. The goal of this study is to better understand the degree to which each of these taxa consumed tough and/or hard food items, including grass, leaves, and woody browse in their respective environments. To this end, we examined the dental microwear of Pleistocene mammoths and mastodons to address the following questions: 1) do mammoths and mastodons with known differences in diet (via carbon isotopes) have similar dental microwear attributes?, 2) do juvenile and adult mammoth and mastodons consume foods with similar textural properties?, and 3) did the Channel Islands mammoths consume food with similar textural properties as the mainland Columbian mammoths? Our results demonstrate that the mammoths and mastodons here examined ate foods with similar textural properties, despite consuming plants with disparate stable isotope values. These data suggest that mammoths and mastodons were generalists (in regards to dietary textures) and did not eat softer or tougher foods as juveniles. Further, the Channel Islands mammoths ate food items with more variable textural properties (including a greater incidence of hard foods) than Columbian mammoths from Texas. While more work is needed to assess the ubiquity of these results across time and space, collectively, these data suggest that extinct proboscideans are generalist feeders similar to extant elephants.

A simulation of anthropogenic Columbian mammoth (Mammuthus columbi) extinction

The cause of the extinction of the Columbian mammoth (Mammuthus columbi) and other species of megafauna during the end of the Pleistocene epoch is an ongoing debate. In this study, we used mathematical modelling to test the overkill hypothesis first proposed by Martin in 1973. The overkill hypothesis claims that early humans migrating from Asia through Beringia and into North America hunted the majority of the continent’s megafauna to extinction. Previous research has been conducted on the overkill hypothesis for the Columbian mammoth using a continuous differential equations model. We improved on this work by developing a computationally more efficient and more realistic discrete stochastic model. Most model parameters were obtained directly from the literature; migration parameters were informed by the literature and calibrated for the model. Our results provide evidence in support of the overkill hypothesis.

Five Younger Dryas black mats in Mexico and their stratigraphic and paleoenvironmental context

The Younger Dryas interval (YD) was a period of widespread, abrupt climate change that occurred between 12,900 and 11,700 cal yr BP (10,900–10,000 14C BP). Many sites in the Northern Hemisphere preserve a sedimentary record across the onset of the YD interval, including sites investigated in sedimentary basins located in central Mexico (Chapala, Cuitzeo, Acambay), the Basin of Mexico (Tocuila), and northern Mexico (El Cedral). Deposits consist of lacustrine or marginal lake sediments that were deposited during the Pleistocene and the Holocene. At the Tocuila and Acambay sites, Pleistocene fossil vertebrate assemblages, mainly mammoths (Mammuthus columbi), are found in association with a distinctive organic layer, sometimes called the black mat that formed during the YD. At the Chapala, Cuitzeo, Acambay, and Tocuila sites the black mats contain a suite of distinctive microscopic and mineralogical signatures and are accompanied by a sharp change in the depositional environments as supported by diatom and pollen studies reported here. The signatures include magnetic, Fe-rich microspherules, silica melted droplets with aerodynamic shapes (tektites), large amounts of charcoal, and sometimes nanodiamonds (Cuitzeo), all of which were deposited at the onset of the YD. The geochemistry of the microspherules indicates that they are not anthropogenic, authigenic or of cosmic or volcanic origin, and instead, were produced by melting and quenching of terrestrial sediments. Here, we present the stratigraphy at five field sites, the analyses of magnetic microspherules, including major element composition and scanning electron microscopy images. All of these materials are associated with charcoal and soot, which are distinctive stratigraphic markers for the YD layer at several sites in Mexico.