Eurybelodon shoshanii: a new Unusual Shovel-tusked Gomphothere From Miocene Neogene Oregon

Eurybelodon shoshanii, an unusual new shovel-tusked gomphothere (Mammalia, Proboscidea) from the late Miocene of Oregon

Author:

Lambert

Abstract:

Unusual shovel-tusked gomphothere material from the late Clarendonian Black Butte Local Fauna (Juntura Formation, Oregon), including a lower tusk, partial upper tusk, and two mandibles including a second and a third molar, has been described and referred to Platybelodon. Platybelodon has the following diagnostic characteristics: molars strongly double-trefoiled; third molar with five lophs; lower tusks short with broad and very flat profiles lacking significant dorsoventral curvature; and lower tusks lacking obvious lamination but instead filled with small, short dentinal rods. However, the Black Butte shovel-tusked gomphothere was referred to Platybelodon despite having the following conflicting features: molars with weakly developed single trefoiling; third molar with only four lophids (the fourth little more than a talonid); broad, moderately flattened, relatively elongated lower tusk with strong dorsal curvature; and lower tusk internal structure showing lamination rather than dentinal rods. In addition, both the upper and lower tusks of the Black Butte shovel-tusker have prominently corrugated enamel cortices, a feature unknown in any other gomphothere. Thus, given the lack of a single clear-cut shared diagnostic feature and the large number of differences between these taxa, the identification of the Black Butte shovel-tusker as Platybelodon must be refuted. Refutation of the Platybelodon identification requires an alternate identification to be made for the Black Butte shovel-tusker. No other known shovel-tusker genus, including the genera Amebelodon, Serbelodon, and Torynobelodon, possesses the unusual combination of tusk and cheek tooth features observed in this animal. Accordingly, it is here referred to a new genus and species, Eurybelodon shoshanii.

Mammoth Evolution and Dispersal Across the Northern Hemisphere

Evolution and dispersal of mammoths across the Northern Hemisphere

Authors:

Lister et al

Abstract:

le of species origins and dispersal, but understanding has been impeded by taxonomic confusion, especially in North America. The Columbian mammoth Mammuthus columbi was thought to have evolved in North America from a more primitive Eurasian immigrant. The earliest American mammoths (1.5 million years ago), however, resemble the advanced Eurasian M. trogontherii that crossed the Bering land bridge around that time, giving rise directly to M. columbi. Woolly mammoth M. primigenius later evolved in Beringia and spread into Europe and North America, leading to a diversity of morphologies as it encountered endemic M. trogontherii and M. columbi, respectively. In North America, this included intermediates (“M. jeffersonii”), suggesting introgression of M. primigenius with M. columbi. The lineage illustrates the dynamic interplay of local adaptation, dispersal, and gene flow in the evolution of a widely distributed species complex.

The Mammoths of Wrangel island

Evolution: The Island of Misfit Mammoths

Author:

Roca

Summary:

The genomes of two woolly mammoths have been sequenced. One of the last survivors had reduced genetic diversity. Although divergent in their mitochondrial genomes, the mammoths had similar nuclear genomes, a finding germane to elephant conservation.

One Small Step to a Woolly Mammoth: Genome Fully Sequence, Cold Adaptions IDed

Elephantid Genomes Reveal the Molecular Bases of Woolly Mammoth Adaptations to the Arctic

Authors:

Lynch et al

Abstract:

Woolly mammoths and living elephants are characterized by major phenotypic differences that have allowed them to live in very different environments. To identify the genetic changes that underlie the suite of woolly mammoth adaptations to extreme cold, we sequenced the nuclear genome from three Asian elephants and two woolly mammoths, and we identified and functionally annotated genetic changes unique to woolly mammoths. We found that genes with mammoth-specific amino acid changes are enriched in functions related to circadian biology, skin and hair development and physiology, lipid metabolism, adipose development and physiology, and temperature sensation. Finally, we resurrected and functionally tested the mammoth and ancestral elephant TRPV3 gene, which encodes a temperature-sensitive transient receptor potential (thermoTRP) channel involved in thermal sensation and hair growth, and we show that a single mammoth-specific amino acid substitution in an otherwise highly conserved region of the TRPV3 channel strongly affects its temperature sensitivity.

Evidence of Butchered Elephant on Stone Tools From Pleistocene Quaternary Israel

Fat Residue and Use-Wear Found on Acheulian Biface and Scraper Associated with Butchered Elephant Remains at the Site of Revadim, Israel

Authors:

Solodenko et al

Abstract:

The archaeological record indicates that elephants must have played a significant role in early human diet and culture during Palaeolithic times in the Old World. However, the nature of interactions between early humans and elephants is still under discussion. Elephant remains are found in Palaeolithic sites, both open-air and cave sites, in Europe, Asia, the Levant, and Africa. In some cases elephant and mammoth remains indicate evidence for butchering and marrow extraction performed by humans. Revadim Quarry (Israel) is a Late Acheulian site where elephant remains were found in association with characteristic Lower Palaeolithic flint tools. In this paper we present results regarding the use of Palaeolithic tools in processing animal carcasses and rare identification of fat residue preserved on Lower Palaeolithic tools. Our results shed new light on the use of Palaeolithic stone tools and provide, for the first time, direct evidence (residue) of animal exploitation through the use of an Acheulian biface and a scraper. The association of an elephant rib bearing cut marks with these tools may reinforce the view suggesting the use of Palaeolithic stone tools in the consumption of large game.

How to Tell What Proboscideans (Elephants and Paleo Relatives) ate Based on Tooth Wear

A new tooth wear-based dietary analysis method for Proboscidea (Mammalia)

Authors:

Saarinen et al

Abstract:

Dietary analyses of herbivorous mammals are important for paleoecological reconstruction. Several methods applicable to fossil teeth have been developed lately. The mesowear method based on wear-induced occlusal shape and relief of ungulate molars has proven to be a robust method for dietary analysis. In its original form it can only be used for selenodont, plagiolophodont, and ectolophodont ungulate molars, but the principle can be extended to other kinds of tooth morphology. We introduce a new method of dietary analysis for proboscideans similar to the mesowear method, based on angle measurements from worn dentin valleys reflecting the relief of enamel ridges. The enamel ridges should be heavily worn when the abrasiveness of diet increases, resulting in lower occlusal relief and larger angles. For testing this, we compared the mesowear angles with stable carbon isotope values from dental enamel from populations of extant and fossil species from localities from Kenya and India. This enables us to compare diet and tooth wear in proboscideans, because the stable carbon isotope ratios in tropical environments provide a reliable standard for assessing the relative amounts of C4 and C3 plants in diet, and most of the C4 plants are grasses, which should be reflected in the mesowear signal.

Harvard Geneticist Inserts Woolly Mammoth Genes Into Elephant Cells Using CRISPR

Researchers from Harvard University have successfully inserted genes from a woolly mammoth into living cells from an Asian elephant, the extinct giant's closest remaining relative.

Harvard geneticist George Church used DNA from Arctic permafrost woolly mammoth samples to copy 14 mammoth genes -- emphasizing those related to its chilly lifestyle.

"We prioritized genes associated with cold resistance including hairiness, ear size, subcutaneous fat and, especially, hemoglobin," Church told The Sunday Times.

Then, using a kind of DNA cut/paste system called CRISPR (clustered regularly interspaced short palindromic repeat), Church dropped the genes into Asian elephant skin cells.

The result? A petri dish of elephant cells functioning normally with mammoth DNA in them, marking the first time mammoth genes have been on the job since the creature went extinct some 4,000 years ago, as Sarah Fecht, from Popular Science, noted.

link.

Evolution of Basal "Elephant" Protanancus in East Asia

Evolution of Protoanancus (Proboscidea, Mammalia) in East Asia

Authors:

Wang et al

Abstract:

Interspecific competition and species replacement explain many evolutionary successions, but these processes are difficult to test. According to recent paleontological research, amebelodontines were predominant proboscideans in faunas of the early to middle Miocene of East Asia. In addition to the abundant Platybelodon, other amebelodontines are known, but they have been largely neglected by researchers. Here we describe two species of Protanancus, Pr. tobieni and Pr. brevirostris, sp. nov., from China. The former was present during the middle Miocene in Tongxin and Qin’an and was previously attributed to Amebelodon or Serbelodon; the latter was present during the early Miocene in the Linxia Basin. Cladistic analysis indicates that the two species appear to represent primitive members of Protanancus. However, the phylogenetic relationship among Protanancus, Platybelodon, and Amebelodon remains unresolved because of their strong parallel evolution. Our study suggests intensive competition between Protanancus and Platybelodon based on similarities in their mandibular morphologies and dental microwear patterns, with the former genus disappearing from East Asia by the late middle Miocene. This scenario is supported by a mechanical model, in which lower tusks with dentinal tubules, as occur in Platybelodon, show greater resistance to the adverse effects of both a heavy load and abrasion than those with concentric laminae, present in Protanancus. The model aids in interpreting the evolution of the inner structure of the lower tusks of amebelodontines, which may have provided a competitive advantages for these species.

Climate Set the South American Stage, but Humans Wiped it Clean of Proboscideans

Climate and humans set the place and time of Proboscidean extinction in late Quaternary of South America

Authors:

Lima-Ribeiro et al

Abstract:

The late Quaternary extinctions have been widely debated for a long time, but the varying magnitude of human vs. climate change impacts across time and space is still an unresolved question. Here we assess the geographic range shifts in response to climate change based on Ecological Niche Models (ENMs) and modeled the timing for extinction under human hunting scenario, and both variables were used to explain the extinction dynamics of Proboscideans during a full interglacial/glacial cycle (from 126 ka to 6 ka) in South America. We found a large contraction in the geographic range size of two Proboscidean species studied (Cuvieronius hyodon and Notiomastodon platensis) across time. The largest contractions of their geographical ranges occurred in the northern part of South America, where we previously reported no evidence of coexistence among earliest humans and non-sloth megafauna, including Proboscideans. Our results herein support a strong effect of climatic changes on geographical range dynamics of Proboscideans throughout late Quaternary, although this does not fully support climate change as the single cause of their extinctions. We show that both Proboscideans were narrowly distributed on scattered patches of suitable habitats (i.e., refugia) around 11 ka, period in which the earliest humans potentially arrived in South America, increasing the population density thereafter. Under this overall unsuitable climatic condition at 11 ka, both Proboscideans would be extinct after around 550 years of human hunting, but if climatic conditions were suitable like in Last Glacial Maximum (LGM), the time-for-extinction would be at least 3 times longer under the same human hunting pressures. Thus, our findings support the “Broken Zig-Zag” model and show that South American Proboscideans might have been completely extinct due to human impacts during periods of climate crisis. We conclude, in agreement with an increasing body of evidence in the recent literature, that the late Quaternary megafaunal extinction event was the result of additive effects from different stressors, and that the relative magnitude of these impacts vary across space and time. Indeed, climate changes set the place where the Proboscideans were extinct in South America, whereas the humans set the time of these extinctions.

DeExtinction: Bring Back the Woolly Mammoth

Wooly Mammoth Blood Extracted?

Read it here and here.

Wooly-Columbian Mammoth Hybrid Found?

Mammoths were a diverse genus that roamed across Eurasia and North America during the Pleistocene era. In continental North America, at least two highly divergent species have long been recognized – woolly mammoths (Mammuthus primigenius) and Columbian mammoths (M. columbi). But new genetic evidence published in BioMed Central's open access journal Genome Biology suggests that these species may have been closely related enough to mate when they had the chance.

Remains of woolly mammoths have been found across the glacial tundra-steppe of Eurasia and northern North America, while the much physically larger Columbian mammoths inhabited the savannah environments of temperate southern and central North America. The differences between the species have long been considered as unique adaptations to the environments where they evolved. But by piecing together trace fragments of DNA from an 11 thousand year-old Columbian mammoth from Fairview, Utah, a team of Canadian, American and French researchers found that surprisingly the mitochondrial genome from this mammoth was nearly indiscernible from that of its northern woolly counterparts.

But the group does not suspect that this requires a re-write of North American mammoth evolution. "We think this individual may have been a woolly-Columbian hybrid," says Jacob Enk of the McMaster Ancient DNA Centre, the group that led the research. "Living African elephant species interbreed where their ranges adjoin, with males of the bigger species out-competing the smaller for mates. This results in mitochondrial genomes from the smaller species showing up in populations of the larger. Since woolly and Columbian ranges periodically overlapped in time and space, it's likely that they engaged in similar behaviour and left a similar genetic signal." The team goes on to suggest that interbreeding may explain some mammoth fossils that have intermediate physical characteristics, between woollies and Columbians, sometimes assigned to the species M. jeffersonii.

They do not rule out other explanations however, and note that the only way to know for sure whether their mammoth was a hybrid is to sequence nuclear DNA from it and other mammoths. For poorly-preserved remains like those of southern-ranging Columbians, this will be a challenge. But they expect that by exploiting new cutting-edge sequencing technologies, the nuclear genomes of these amazing animals are within reach.

...

Just In: Reports of Gompotheres Ghost Lineage...from 13,500 years ago?!

(image source: Karen Carr)

Sometime during 2007, a rancher in the northern Mexican state of Sonora took a visitor to see large bones he had found in an arroyo, or creek bed. The visitor was Guadalupe Sanchez, who works for Mexico’s INAH (Instituto Nacional de Antropología e Historia). It turns out that the bones were not the only item that piqued Guadalupe’s interest; several stone implements were found in association with them. What makes this discovery so very special and highly interesting is the kind of animal the bones belonged to and the nature of the stone tools.

After two years of hushed up investigations, the scientists recently announced that these bones represent two juvenile gomphotheres and the tools belong to the so-called Clovis tradition, a topic which has been the subject of earlier blog entries . The focus here is not on who came first, Clovis or others (that argument has been settled anyway), but rather on the implications of the find of the Gomphothere bones together with Paleoindian tools like those of the Clovis tradition. That is what is drawing the attention of a lot of North American archaeologists these days. In a nutshell, what we have here is described as “the first documentation that there was some sort of human interaction with gomphotheres in North America.”

DUDE!

No time to comment, but gomphotheres in nearly the fscking Holocene?!

WOW!

I wonder if this will hold up?

Hat tip: Beyond Bones.

Mastodon Fossil Finds in Indiana, Michigan

Mine workers in southwestern Indiana have unearthed the tusks and skeletal remains of a prehistoric elephant that lived more than 12,000 years ago.

The workers were digging a coal slurry storage pit recently at Vectren's Black Panther Mine about 30 miles south of Terre Haute when they noticed the fossil mastodon bones in a backhoe shovel.

After realizing the importance of the find, the crew notified the Indiana Division of Reclamation, which regulates mining operations.

Division of Reclamation archaeologist Tim Wright praised the workers for saving the fossils of the prehistoric elephant and contacting the state.

"It's just an accident they ran into it and they did the right thing by notifying us," Wright said.

He said the bones include pieces of ribs, skull, tusks and a kneecap. The fossilized remains have been turned over to the Indiana State Museum for further study and preservation.

Wright said Vectren has set aside the dirt in which the fossils were found. Paleontologists from the state museum have conducted more searches for additional remains.

[...]

Last month, a couple in central Michigan found the bones of a 10,000-plus-year-old mastodon. Rich and Annette Schneider planned to put a pond in their backyard in Portland, Mich. and the dig turned up bones including a leg, a rib and a tusk.

I wonder how accurate that 10k yo dating is.

The Paleocene Emergence of Proboscidea

Paleocene emergence of elephant relatives and the rapid radiation of African ungulates

1. Emmanuel Gheerbrant

Unité Mixte de Recherche 7207, Centre National de la Recherche Scientifique, Centre de Recherches sur la Paléobiodiversité et les Paléoenvironnements, Case 38, Département Histoire de la Terre, Muséum National d'Histoire Naturelle, 8, Rue Buffon, 75005 Paris, France

Abstract:

Elephants are the only living representatives of the Proboscidea, a formerly diverse mammalian order whose history began with the 55-million years (mys) old Phosphatherium. Reported here is the discovery from the early late Paleocene of Morocco, ca. 60 mys, of the oldest and most primitive elephant relative, Eritherium azzouzorum n.g., n.sp., which is one of the earliest known representatives of modern placental orders. This well supported stem proboscidean is extraordinarily primitive and condylarth-like. It provides the first dental evidence of a resemblance between the proboscideans and African ungulates (paenungulates) on the one hand and the louisinines and early macroscelideans on the other. Eritherium illustrates the origin of the elephant order at a previously unknown primitive stage among paenungulates and “ungulates.” The primitive morphology of Eritherium suggests a recent and rapid paenungulate radiation after the Cretaceous-Tertiary boundary, probably favoured by early endemic African paleoecosystems. At a broader scale, Eritherium provides a new old calibration point of the placental tree and supports an explosive placental radiation. The Ouled Abdoun basin, which yields the oldest known African placentals, is a key locality for elucidating phylogeny and early evolution of paenungulates and other related endemic African lineages.

Interesting, interesting.

I'm reading Splendid Isolation right now and I have a few questions on Ungulate evolution...this is just adding to it. More later.