Camelops Research Articles

A new specimen of Camelops hesternus (Artiodactyla, Camelidae) from Valsequillo, Puebla, Mexico, with comments about their dietary preferences and the population density of the species

Camelidae is one of the most diverse and successful artiodactyl families, with a long geological history and wide geographical range in North America. Camelops hesternus was the one of last camelids in North America during the Pleistocene (Rancholabrean) and its remains have been found from Alaska south into Mexico. Here, we describe a new specimen of this species based on a complete mandible from the Late Pleistocene sediments of the Cerro Grande de la Mesa Calderón monogenetic volcano in the Valsequillo Basin, Puebla, central Mexico. A mesowear analysis of the dentition indicates wear in the new specimen to be similar to that of the Klipspringer, Oreotragus oreotragus, indicating a browsing diet. The population density of C. hesternus in the Valsequillo Basin was estimated using a differential non-linear equations mathematical model under three scenarios (stress, optimal, and abundance conditions) a indicating the range in its population density of 0.51–1.8 ind/km2, and this species was not abundant in the region. Despite the low population density C. hesternus has been reported in Mexico from 27 Pleistocene localities, with a geographic range from north (29°40′ latitude, Sonora) to south (16°14′ latitude, Chiapas) at an altitude range of 0–200 m asl in Baja California Sur to 2500 m asl in the Trans-Mexican Volcanic Belt.

Environmental inferences based on the dietary ecology of camelids from west-central Mexico during the Late Pleistocene

ABSTRACT Fossil camelids (Artiodactyla, Camelidae) record for Mexican Late Pleistocene is constituted by Camelops hesternus, Hemiauchenia macrocephala, Hemiauchenia gracilis, and Palaeolama mirifica. It analysed dental microwear and carbon and oxygen stable isotopes in teeth enamel of C. hesternus, H. macrocephala and H. gracilis from two fossil sites (LC-PT, and LP-SA) in west-central Mexico, gaining knowledge about camelids palaeoecology (diet and habitat). Microwear and δ13C values indicate that C. hesternus from both sites had a browser diet with a preference for C3-C4 plants, while H. macrocephala from LC-PT was browser with a predilection for C3 plants, and H. gracilis from LC-PT had a mixed feeder diet with a preference for C3 plants. The δ18O and the aridity index show that camelids in central Mexico were evaporation-sensitive taxa. The results suggest that LC-PT had a heterogeneous environment composed of open areas and closed zones, temperatures between 13.95°C and 19.9°C and extreme seasonal changes. The environment in LP-SA was dominated by open areas, with small closed vegetation patches, a temperature of 16.29°C, and less seasonal variation. The aridity index indicates relatively drier conditions at LP-SA than at LC-PT. Camelid dietary ecology provides an initial reconstruction of a regional paleoenvironment, with diverse ecosystems present.

Paleobiology of a large mammal community from the late Pleistocene of Sonora, Mexico

AbstractA paleontological deposit near San Clemente de Térapa represents one of the very few Rancholabrean North American Land Mammal Age sites within Sonora, Mexico. During that time, grasslands were common, and the climate included cooler and drier summers and wetter winters than currently experienced in northern Mexico. Here, we demonstrate restructuring in the mammalian community associated with environmental change over the past 40,000 years at Térapa. The fossil community has a similar number of carnivores and herbivores whereas the modern community consists mostly of carnivores. There was also a 97% decrease in mean body size (from 289 kg to 9 kg) because of the loss of megafauna. We further provide an updated review of ungulates and carnivores, recognizing two distinct morphotypes ofEquus, includingE.scottiand a slighter species; as well asPlatygonus compressus;Camelops hesternus;Canis dirus; andLynx rufus;and the first regional records ofPalaeolama mirifica,Procyon lotor, andSmilodoncf.S.fatalis. The Térapa mammals presented here provide a more comprehensive understanding of the faunal community restructuring that occurred in northern Mexico from the late Pleistocene to present day, indicating further potential biodiversity loss with continued warming and drying of the region.

Propagation of fungi in the soils: A case study of scientific experimental fields of forestry of Tashkent region

The sphere of forestry in our republic is developing in the current years. For the purpose of landscaping the territory of our country, reproduction and cultivation of virginia firs, abina firs, pine species, cypress trees, eastern biota, western camel, spruce and other deciduous trees from coniferous trees is widely established. These ornamental trees differ from other ornamental trees and shrubs in their heat–cold, drought resistance. Different landscapes and forest trees are initially planted in germination plants and seedlings from their seeds. In Uzbekistan, diseases of decorative and forest trees, especially their diseases in the germination period, have almost not been studied. The fact that many different diseases are encountered in landscape trees in recent years is known from different sources. The article provides information on the influence of the seasons on the spread of fungi that have appeared on the soil of some plantations and seedlings in Tashkent region.

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.

ФІНАНСОВИЙ СТАН БАНКУ ТА МЕТОДИ ЙОГО ОЦІНКИ В УКРАЇНІ

To ensure the effective functioning and development of the economy of any country, a stable banking system is necessary. The stability of the banking system affects the state of the economy and contributes to its growth, so the analysis of the financial condition of banking institutions is a priority function of state bodies that regulate the banking sector. Reliable and timely analysis of the Bank's financial condition is the key to making effective financial decisions on the part of owners, investors, partners, employees of the tax service and other participants in economic relations aimed at reducing costs, increasing profits and market value of the company. Regular analysis of the Bank's activities allows it to effectively manage active and passive operations in order to maximize profits and ensure a stable financial condition.The article considers approaches to the definition of the concept «financial condition of a Bank» that currently exist in the literature, and it is established that there are many opinions on the definition of the concept «financial condition of a Bank». But, despite the fact that the opinions of a number of authors coincide, this issue requires further study. The article discusses the main goals and objectives of the analysis of the Bank's financial condition. The main methods of analysis of the Bank's financial condition are defined. These include: coefficient analysis, rating analysis, mathematical and statistical models. A comparative analysis of the coefficients that are used to analyze the financial condition of the Bank, as well as the standards established by the National Bank of Ukraine. The most common rating model for assessing the Bank's financial condition – the American CAMELS system-is described.

Pleistocene paleoecology and feeding behavior of terrestrial vertebrates recorded in a pre-LGM asphaltic deposit at Rancho La Brea, California

Sixteen taxa comprising extinct megafauna and extant species from a single asphalt deposit (Project 23, Deposit 1) at Rancho La Brea were isotopically analyzed (δ13C, δ15N, δ34S) and 14C dated to investigate paleoecology and feeding behavior of terrestrial vertebrates in southern California during the late Pleistocene. The large majority of the 14C dates cluster between ~35 and 36 kyr BP, but a range of ages indicate this seep was active from ~30 to >43 kyr BP. Many of the Smilodon fatalis and Canis dirus as well as the Canis latrans have similar δ13C (~–19‰ to −18‰) and δ15N (~11‰ to 12‰) results, indicating that these predators may have consumed similar prey species and possibly competed with each other through hunting and/or scavenging. The remains of contemporary potential prey species for these three predators include juvenile Bison antiquus and Camelops hesternus, and possibly adult Paramylodon harlani and Capromeryx minor. However, the δ15N results of a single C. dirus (8.9‰) and the Panthera atrox (8.3‰) were significantly lower than the other large predators. Potential prey for this dire wolf and lion include Nothrotheriops shastensis, Equus occidentalis and possibly Mammut americanum. Many of the herbivores appear to have utilized broadly similar C3 ecological environments. However, the adult E. occidentalis had isotopic results similar to the Sylvilagus sp. and Spermophilus beecheyi that have restricted home ranges, suggesting this horse was similarly local in its distribution or consumed a similar plant food selection. The isotopic values for extant taxa (Actinemys marmorata, Crotalus sp., Mustela frenata) suggest similar dietary patterns to their modern counterparts, indicating their ecological niches have remained relatively constant. The results presented here establish a foundation for future diachronic studies to better understand how the climate of the last ~50 kyr BP impacted biodiversity and ecological communities in southern California.

Collagen sequence analysis of fossil camels, Camelops and c.f. Paracamelus, from the Arctic and sub-Arctic of Plio-Pleistocene North America

Proteomic analyses of ancient remains are increasing in number and offer great potential to recover phylogenetic information on extinct animals beyond the reach of ancient DNA, but limitations in proteomic techniques remain unclear. Here we carry out LC-MS/MS sequence analysis of a ~3.5 million year old giant camel specimen from Nunavut along with the younger Pleistocene remains of the Yukon giant camel (c.f. Paracamelus) and the western camel (Camelops hesternus) for comparison with complete sequences to both extant camels (Bactrian and Dromedary) and the alpaca. Although not complete (~75–80% sequence coverage), no amino acid sequence differences were confidently observed between the giant camels and the extant Dromedary, indicative of a closer relationship than that of the extant Bactrian lineage. However, multiple amino acid changes were observed for the western camel (Camelops) collagen sequence, placing it as a sister group to these members of the Camelini tribe consistent recent ancient DNA analyses. Although this supports a role for the sequencing of ancient collagen in the understanding of vertebrate evolution, these analyses highlight the limitations in phylogenetic reconstructions based on partial sequence data retrieved from proteomic analyses, particularly, the impact of omitting even only a single peptide on the resulting tree topology. The presence of other non-collagenous proteins, such as biglycan and PEDF, indicates a further resource for phylogenetic information, but none more promising than the degraded camel albumin seemingly observed in the Pliocene specimen. SignificanceAs proteomics is becoming more frequently used in the study of ancient proteins, an emerging field known as ‘palaeoproteomics’ (or ‘paleoproteomics’), understanding the limitations of the technique is essential.Here, through the study of the oldest undisputed collagen sequences obtained from proteomics, we confirm that some peptides following diagenetic modifications of tryptic sites are no longer matched with standard searches, but can be matched with Error Tolerant searches.We also demonstrate the ability to retrieve phylogenetic information consistent with that of ancient DNA methods, but that with the omission of only one or more key peptides, the inferred evolutionary relationships change. This is a significant finding for the field of palaeoproteomics implying a need for better understanding the particular composition of the partial sequences retrieved from proteomic analyses.

Rancho La Brea Fossil Indicates Native Nearctic Status for Necrobia violacea (Linnaeus) (Coleoptera: Cleridae), a Species Previously Considered a Synanthropic Introduction to North America

The cosmopolitan beetle Necrobia violacea (Linnaeus) (Cleridae), formerly thought adventive in the New World through European trade, is reported from a sealed assemblage within the skull of a western camel (Camelops hesternus Leidy, Camelidae) from the famous Rancho La Brea Tar Pits in southern California and radiocarbon dated to approximately 44,000 years ago. The biogeographical significance of this find is discussed in the context of other pre-Columbian records of members of the genus Necrobia Olivier.

A case of early Wisconsinan “over-chill”: New radiocarbon evidence for early extirpation of western camel (Camelops hesternus) in eastern Beringia

There are comparatively few fossils that document the presence of the Pleistocene western camel (Camelops hesternus) in the unglaciated regions of Alaska and Yukon, northwestern North America (eastern Beringia). It has been previously reported on the basis of stratigraphic and radiocarbon data that this species was present within this region from the Sangamonian interglaciation (Marine Isotope Stage (MIS) 5) through the Last Glacial Maximum (LGM, MIS 2). However, the continued presence of western camel through the LGM is at odds with its ecological preferences as inferred from more southerly parts of the continent. Here we report 43 new radiocarbon dates on 34 western camel fossils from Alaska and Yukon, including specimens that have been dated previously. To minimize exogenous carbon contamination, we utilized either ultrafiltered collagen or single amino acid (hydroxyproline) methodologies in conducting the analyses. All samples, including previously reported specimens with finite ages, yielded ages that were either non-finite or close to the effective limit of radiocarbon dating. These results indicate that dates implying local presence of western camels in Alaska and Yukon during full-glacial conditions of MIS 2 are erroneous by as much as several tens of millennia, probably because of carbon contamination from glue or varnish used in fossil preparation and conservation. The revised radiocarbon chronology, together with other evidence, indicates that western camels were only able to occupy eastern Beringia only during Pleistocene interglaciations such as MIS 5, when forests and shrublands became the dominant regional biomes. The subsequent transition to cold, arid full-glacial conditions during the early Wisconsinan glaciation (MIS 4) around 75 000 years ago created unfavorable environmental conditions, eliminated browse, and led to their local extirpation in eastern Beringia. After their complete population loss in the Arctic and Subarctic, the range of western camels was restricted to the temperate mid-continent, where they eventually went extinct ∼13 000 years ago.

The Tule Springs local fauna: Rancholabrean vertebrates from the Las Vegas Formation, Nevada

A middle to late Pleistocene sedimentary sequence in the upper Las Vegas Wash, north of Las Vegas, Nevada, has yielded the largest open-site Rancholabrean vertebrate fossil assemblage in the southern Great Basin and Mojave Deserts. Recent paleontologic field studies have led to the discovery of hundreds of fossil localities and specimens, greatly extending the geographic and temporal footprint of original investigations in the early 1960s. The significance of the deposits and their entombed fossils led to the preservation of 22,650 acres of the upper Las Vegas Wash as Tule Springs Fossil Beds National Monument. These discoveries also warrant designation of the assemblage as a local fauna, named for the site of the original paleontologic studies at Tule Springs.The large mammal component of the Tule Springs local fauna is dominated by remains of Mammuthus columbi as well as Camelops hesternus, along with less common remains of Equus (including E. scotti) and Bison. Large carnivorans including Canis dirus, Smilodon fatalis, and Panthera atrox are also recorded. Micromammals, amphibians, lizards, snakes, birds, invertebrates, plant macrofossils, and pollen also occur in the deposits and provide important and complementary paleoenvironmental information. The fauna occurs within the Las Vegas Formation, an extensive and stratigraphically complex sequence of groundwater discharge deposits that represent a mosaic of desert wetland environments. Radiometric and luminescence dating indicates the sequence spans the last ∼570 ka, and records hydrologic changes in a dynamic and temporally congruent response to northern hemispheric abrupt climatic oscillations. The vertebrate fauna occurs in multiple stratigraphic horizons in this sequence, with ages of the fossils spanning from ∼100 to ∼12.5 ka.

Vertebrate paleontology, stratigraphy, and paleohydrology of Tule Springs Fossil Beds National Monument, Nevada (USA)

Tule Springs Fossil Beds National Monument (TUSK) preserves 22,650 acres of the upper Las Vegas Wash in the northern Las Vegas Valley (Nevada, USA). TUSK is home to extensive and stratigraphically complex groundwater discharge (GWD) deposits, called the Las Vegas Formation, which represent springs and desert wetlands that covered much of the valley during the late Quaternary. The GWD deposits record hydrologic changes that occurred here in a dynamic and temporally congruent response to abrupt climatic oscillations over the last ~300 ka (thousands of years). The deposits also entomb the Tule Springs Local Fauna (TSLF), one of the most significant late Pleistocene (Rancholabrean) vertebrate assemblages in the American Southwest. The TSLF is both prolific and diverse, and includes a large mammal assemblage dominated by Mammuthus columbi and Camelops hesternus. Two (and possibly three) distinct species of Equus, two species of Bison, Panthera atrox, Smilodon fatalis, Canis dirus, Megalonyx jeffersonii, and Nothrotheriops shastensis are also present, and newly recognized faunal components include micromammals, amphibians, snakes, and birds. Invertebrates, plant macrofossils, and pollen also occur in the deposits and provide important and complementary paleoenvironmental information. This field compendium highlights the faunal assemblage in the classic stratigraphic sequences of the Las Vegas Formation within TUSK, emphasizes the significant hydrologic changes that occurred in the area during the recent geologic past, and examines the subsequent and repeated effect of rapid climate change on the local desert wetland ecosystem.

Vertebrate paleontology, stratigraphy, and paleohydrology of Tule Springs Fossil Beds National Monument, Nevada (USA)

Tule Springs Fossil Beds National Monument (TUSK) preserves 22,650 acres of the upper Las Vegas Wash in the northern Las Vegas Valley (Nevada, USA). TUSK is home to extensive and stratigraphically complex groundwater discharge (GWD) deposits, called the Las Vegas Formation, which represent springs and desert wetlands that covered much of the valley during the late Quaternary. The GWD deposits record hydrologic changes that occurred here in a dynamic and temporally congruent response to abrupt climatic oscillations over the last ~300 ka (thousands of years). The deposits also entomb the Tule Springs Local Fauna (TSLF), one of the most significant late Pleistocene (Rancholabrean) vertebrate assemblages in the American Southwest. The TSLF is both prolific and diverse, and includes a large mammal assemblage dominated by Mammuthus columbi and Camelops hesternus. Two (and possibly three) distinct species of Equus, two species of Bison, Panthera atrox, Smilodon fatalis, Canis dirus, Megalonyx jeffersonii, and Nothrotheriops shastensis are also present, and newly recognized faunal components include micromammals, amphibians, snakes, and birds. Invertebrates, plant macrofossils, and pollen also occur in the deposits and provide important and complementary paleoenvironmental information. This field compendium highlights the faunal assemblage in the classic stratigraphic sequences of the Las Vegas Formation within TUSK, emphasizes the significant hydrologic changes that occurred in the area during the recent geologic past, and examines the subsequent and repeated effect of rapid climate change on the local desert wetland ecosystem.

Dietary ecology of ungulates from the La Brea tar pits in southern California: A multi-proxy approach

The La Brea Tar Pits are a highly fossiliferous late Pleistocene locality, with over 230 vertebrate species, and the potential to help clarify the ecology of Pleistocene megafauna prior to their extinction. Here, we analyze dental microwear textures, dental mesowear, and stable carbon isotopes to assess the dietary behavior of the three most abundant ungulates at La Brea. We examined Bison antiquus, Camelops hesternus, and Equus occidentalis teeth from pits spanning the latest Pleistocene, focusing on pit 77 (~35Ka, glacial period), and pits 61/67 (~11.5Ka, interglacial period). Dental microwear attributes demonstrate that B. antiquus and E. occidentalis consumed foods with similar textural properties to those preferred by mixed feeding and browsing bovids, as well as significantly different food textures than the diet of modern bison and horses. Camelops hesternus has attributes most similar to modern browsing bovids and giraffes, revealing that all taxa studied likely consumed at least some woody browse. Complexity values (Asfc) in B. antiquus and E. occidentalis are significantly greater at pit 77 than at pits 61/67 and modern populations, suggesting a dietary decrease in woody vegetation and shrubs from the glacial to interglacial period. Dental mesowear values further indicate that B. antiquus and C. hesternus consumed woody vegetation, whereas E. occidentalis grazed. The different dietary interpretation for E. occidentalis may reflect a discrepancy between its average diet inferred from mesowear and its most recent diet inferred from microwear. Lastly, stable carbon isotopes reveal diets composed mostly of C3 vegetation, with B. antiquus incorporating significantly more C4 vegetation than either of the other dominant herbivores during the accumulation of both assemblages. Collectively, these data suggest that the dietary ecology of the dominant La Brea herbivores was more nuanced than previously thought, shifting coincident with changing climates, and not necessarily predictable from morphology or any one proxy method.

The record of camelids (Artiodactyla, Camelidae) from the Valsequillo Basin, late Pleistocene of Puebla State, Central Mexico: taxonomy, diet, and geographic distribution

Dental and postcranial fossil material referable to camelids, which has been recovered from Quaternary deposits that outcrop in the Valsequillo Basin, Puebla State, central Mexico, is formally described. A comparative study indicates the presence of two species of camelids, including Hemiauchenia macrocephala and Camelops hesternus. The sample referable to H. macrocephala includes maxillary and mandibular fragments, isolated teeth, and several postcranial remains (astragalus, metapodials, and proximal phalanges), which show the following diagnostic features of the species: molariforms covered by a layer of cementum; a mandible increasing in depth from p4 to m3; p4 triangular in outline; long and slender metapodials; and proximal phalanges with a W-shaped suspensory ligament scar. The sample referable to C. hesternus is represented by maxillary and mandibular fragments, isolated teeth, and metapodials, sharing with the species its large size; P4 quadrate in outline; p4 triangular in outline and simply folded; and a mandible that is significantly deeper from p4 to m3. A microwear analysis was performed in order to characterize the diet of studied samples, indicating a browser and mixed feeding behavior in H. macrocephala and C. hesternus respectively. The differences in size and trophic regimes in these species should explained the resource partitioning between them. In the late Pleistocene these camelids were common in Mexican sites between the 19°-25° N, and the record from the Valsequillo Basin is one of the few sites where both species have been reported.

Radiocarbon Dating and Stable Isotopic Analysis of Insect Chitin from the Rancho La Brea Tar Pits, Southern California

AbstractThis paper presents the first successful methods for accelerator mass spectrometry (AMS) dating of asphalt-impregnated insect chitin from the Rancho La Brea Tar Pits in southern California. A persistent problem with stratigraphic correlation at this site is that asphalt flows are characteristically intermittent and are really discontinuous, which can result in mixing fossils of quite different ages. Direct14C dating of specimens circumvents this difficulty but requires a pretreatment method that can produce dates from relatively small samples (<10 mg) of insect cuticle, while successfully removing residual asphalt and sample preparation solvents as well as soil carbon contamination.14C dating accuracy was verified by comparing dates on insect chitin with ages for seeds and twigs compacted during a rapid entrapment event within a separately dated skull of the Western Camel,Camelops hesternusLeidy. All dates fell within a relatively narrow range of ~40,000–44,00014C yr BP, suggesting that such methods can be used with confidence on other insect material from this site. Insects are often superior paleoenvironmental indicators for establishing precise data points for climate fluctuations. This is because their lifecycles and present-day climate-restricted geographic distributions are well documented, and unlike migrating mammals and birds, insects offer crucial information about the local environment. Our results are therefore potentially significant for studies of paleoecological and paleoclimatic change within the Los Angeles Basin and coastal southern California, as well as reconstruction of entrapment events at Rancho La Brea.

A review of Camelops (Mammalia, Artiodactyla, Camelidae), a giant llama from the Middle and Late Pleistocene (Irvingtonian and Rancholabrean) of North America

Camelops is a giant llama from the Pliocene and Pleistocene of western North America. Of the 17 species (most, if not all, from the Irvingtonian and Rancholabrean North American Land Mammal Ages) that have been referred to Camelops, only 6 are currently recognised as valid. This review examines Camelops from the Irvingtonian and Rancholabrean (Middle and Late Pleistocene) and describes for the first time material from the latest Wisconsinan of the Nueces River valley of South Texas. During this interval, there are two valid previously named species: the smaller mainly Irvingtonian Camelops minidokae and the larger, mainly Rancholabrean Camelopshesternus. Camelops hesternus, Camelops sulcatus, Camelops huerfanensis and Camelopstraviswhitei are junior synonyms of Camelopshesternus. In addition, there are possibly two additional species: one with short, broad metapodials and one with short, slender metapodials.

Genomic Data from Extinct North American Camelops Revise Camel Evolutionary History.

Recent advances in paleogenomic technologies have enabled an increasingly detailed understanding of the evolutionary relationships of now-extinct mammalian taxa. However, a number of enigmatic Quaternary species have never been characterized with molecular data, often because available fossils are rare or are found in environments that are not optimal for DNA preservation. Here, we analyze paleogenomic data extracted from bones attributed to the late Pleistocene western camel, Camelops cf. hesternus, a species that was distributed across central and western North America until its extinction approximately 13,000 years ago. Despite a modal sequence length of only around 35 base pairs, we reconstructed high-coverage complete mitochondrial genomes and low-coverage partial nuclear genomes for each specimen. We find that Camelops is sister to African and Asian bactrian and dromedary camels, to the exclusion of South American camelids (llamas, guanacos, alpacas, and vicuñas). These results contradict previous morphology-based phylogenetic models for Camelops, which suggest instead a closer relationship between Camelops and the South American camelids. The molecular data imply a Late Miocene divergence of the Camelops clade from lineages that separately gave rise to the extant camels of Eurasia. Our results demonstrate the increasing capacity of modern paleogenomic methods to resolve evolutionary relationships among distantly related lineages.

Late Pleistocene Vertebrates from a Rockshelter in Cimarron County, Oklahoma

Abstract We studied fossils of late Pleistocene vertebrates that were excavated in 1940 from a small rockshelter in Cimarron County, Oklahoma. The assemblage consists of a Canada goose (Branta canadensis) and 14 mammals. Most of the mammals are large or medium-sized indicating a bias in the method of collecting. The assemblage includes Branta canadensis, Mammuthus cf. M. columbi, Cynomys, Neotoma, Lepus, Sylvilagus, Vulpes velox, Canis latrans, Canis lupus, cf. Lynx, Equus cf. conversidens, Equus cf. niobrarensis, Camelops hesternus, Antilocapridae, and Bison. Noteworthy among these is one of the few available late Pleistocene records of the swift fox, Vulpes velox. A piece of enamel from the mammoth at the locality yielded a radiocarbon age of 23,980 ± 130 years before present.

Late Pleistocene Western Camel (Camelops Hesternus) Hunting in Southwestern Canada

AbstractLate Pleistocene large mammal extinctions in North America have been attributed to a number of factors or combination of factors, primarily climate change and human hunting, but the relative roles of these factors remain much debated. Clo-vis-period hunters exploited species such as mammoth, but many now extinct species such as camels were seemingly not hunted. Archaeological evidence from the Wally’s Beach site in southern Canada, including stone tools and butchered bone, provide the first evidence that Clovis people hunted North American camels. Archaeologists generally dismiss human hunting as a significant contributor to Pleistocene extinctions in North America, but Wally’s Beach demonstrates that human hunting was more inclusive than assumed and we must continue to consider hunting as a factor in Pleistocene extinctions.