Discovery of the fossil otter
            Enhydritherium terraenovae
            (Carnivora, Mammalia) in Mexico reconciles a palaeozoogeographic mystery

The North American fossil otter Enhydritherium terraenovae is thought to be partially convergent in ecological niche with the living sea otter Enhydra lutris , both having low-crowned crushing teeth and a close association with marine environments. Fossil records of Enhydritherium are found in mostly marginal marine deposits in California and Florida; despite presence of very rich records of fossil terrestrial mammals in contemporaneous localities inland, no Enhydritherium fossils are hitherto known in interior North America. Here we report the first occurrence of Enhydritherium outside of Florida and California, in a land-locked terrestrial mammal fauna of the upper Miocene deposits of Juchipila Basin, Zacatecas State, Mexico. This new occurrence of Enhydritherium is at least 200 km from the modern Pacific coastline, and nearly 600 km from the Gulf of Mexico. Besides providing further evidence that Enhydritherium was not dependent on coastal marine environments as originally interpreted, this discovery leads us to propose a new east-to-west dispersal route between the Florida and California Enhydritherium populations through central Mexico. The proximity of the fossil locality to nearby populations of modern neotropical otters Lontra longicaudis suggests that trans-Mexican freshwater corridors for vertebrate species in riparian habitats may have persisted for a prolonged period of time, pre-dating the Great American Biotic Interchange.

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Late Cretaceous stratigraphy and vertebrate faunas of the Markagunt, Paunsaugunt, and Kaiparowits plateaus, southern Utah

Geology of the Intermountain West ◽

10.31711/giw.v3i0.10 ◽

2016 ◽

Vol 3 ◽

pp. 229-291 ◽

Cited By ~ 1

Author(s):

Alan L. Titus ◽

Jeffrey G. Eaton ◽

Joseph Sertich

Keyword(s):

Late Cretaceous ◽

Foreland Basin ◽

Alluvial Plain ◽

Terrestrial Vertebrate ◽

The North ◽

Single Region ◽

The World ◽

Kaiparowits Plateau ◽

Fossil Preservation ◽

Fossil Records

The Late Cretaceous succession of southern Utah was deposited in an active foreland basin circa 100 to 70 million years ago. Thick siliciclastic units represent a variety of marine, coastal, and alluvial plain environments, but are dominantly terrestrial, and also highly fossiliferous. Conditions for vertebrate fossil preservation appear to have optimized in alluvial plain settings more distant from the coast, and so in general the locus of good preservation of diverse assemblages shifts eastward through the Late Cretaceous. The Middle and Late Campanian record of the Paunsaugunt and Kaiparowits Plateau regions is especially good, exhibiting common soft tissue preservation, and comparable with that of the contemporaneous Judith River and Belly River Groups to the north. Collectively the Cenomanian through Campanian strata of southern Utah hold one of the most complete single region terrestrial vertebrate fossil records in the world.

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Evidence of Unknown Paleo-Tsunami Events along the Alas Strait, West Sumbawa, Indonesia

Geosciences ◽

10.3390/geosciences11020046 ◽

2021 ◽

Vol 11 (2) ◽

pp. 46

Author(s):

Bachtiar W. Mutaqin ◽

Franck Lavigne ◽

Patrick Wassmer ◽

Martine Trautmann ◽

Puncak Joyontono ◽

...

Keyword(s):

Radiocarbon Dating ◽

Pyroclastic Flows ◽

Western Coast ◽

Eastern Shore ◽

Tsunami Deposits ◽

The West ◽

Marine Deposits ◽

Sedimentary Records ◽

The North ◽

Large Earthquakes

Indonesia is exposed to earthquakes, volcanic activities, and associated tsunamis. This is particularly the case for Lombok and Sumbawa Islands in West Nusa Tenggara, where evidence of tsunamis is frequently observed in its coastal sedimentary record. If the 1815 CE Tambora eruption on Sumbawa Island generated a tsunami with well-identified traces on the surrounding islands, little is known about the consequences of the 1257 CE tremendous eruption of Samalas on the neighboring islands, and especially about the possible tsunamis generated in reason of a paucity of research on coastal sedimentary records in this area. However, on Lombok Island, the eruption of the Samalas volcano produced significant volumes of pyroclastic flows that entered the sea in the North and East of the island. These phenomena must have produced a tsunami that left their traces, especially on Sumbawa Island, whose western coastline is only 14 km away from Lombok’s eastern shore. Therefore, the main goal of this study is to investigate, find evidence, and determine the age of marine-origin sediments along the shore of the Alas Strait, Indonesia. We collected and analyzed samples of coral and seashells from marine deposits identified along the west coast of Sumbawa, i.e., in Belang Island and abandoned fishponds in Kiantar Village, in order to identify the sources and the occurrence period of these deposits events. Based on the radiocarbon dating of coral and seashell samples, we concluded that none of the identified marine deposits along the western coast of Sumbawa could be related chronologically to the 1257 CE eruption of Samalas. However, possible tsunami deposits located in Belang Island and abandoned fishponds in Kiantar Village yielded 4th century CE, 9th century CE, and 17th century CE. We also conclude that past large earthquakes triggered these tsunamis since no known volcanic eruption occurred near the Alas Strait at that time that may have triggered a tsunami.

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The distribution, cellular structure, and metabolism of adipose tissue in the fin whale, Balaenoptera physalus

Canadian Journal of Zoology ◽

10.1139/z88-077 ◽

1988 ◽

Vol 66 (2) ◽

pp. 534-537 ◽

Cited By ~ 9

Author(s):

Caroline M. Pond ◽

Christine A. Mattacks

Keyword(s):

Adipose Tissue ◽

North Atlantic ◽

Glucose Utilization ◽

Significant Activity ◽

Balaenoptera Physalus ◽

Tissue Samples ◽

Fin Whale ◽

Terrestrial Mammals ◽

The North ◽

Adipocyte Volume

The gross mass, mean adipocyte volume, and hexokinase and phosphofructokinase activities of blubber and internal adipose tissue were measured from fin whales (Balaenoptera physalus) caught in the North Atlantic west of Iceland. Fin whale adipocytes are smaller but more numerous than predictions from allometric equations relating adipose tissue structure to body mass, but the deviations are no greater than those of some terrestrial mammals, including humans. Significant activity of the glycolytic enzymes was measured from all adipose tissue samples except those around the eyeball; the activities of hexokinase and phosphofructokinase measured at room temperature are only slightly lower in the blubber than in the internal adipose depots. There was little evidence for metabolic correlates of the site-specific differences in the structure and chemistry of blubber. The highest capacity for glucose utilization was measured in adipose tissue from depots in the neck and the thorax, both of which may contain thermogenic tissue in neonates.

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Shallow Offshore Geophysical Prospection of Archaeological Sites in Eastern Mediterranean

Remote Sensing ◽

10.3390/rs13071237 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1237

Author(s):

Nikos Papadopoulos

Keyword(s):

Eastern Mediterranean ◽

Archaeological Sites ◽

Cultural Resources ◽

Marine Environments ◽

Resistivity Tomography ◽

Cultural Resources Management ◽

Coastal Marine ◽

Ground Penetrating ◽

Magnetic Gradiometry ◽

Geophysical Prospection

Geophysical prospecting methods have been extensively used to outline buried antiquities in terrestrial sites. Despite the frequent application of these mapping and imaging approaches for the detection of archaeological relics in deep-water marine environments (e.g., shipwrecks), the aforementioned processes have minimal contribution when it comes to understanding the dynamics of the past in coastal and shallow aquatic archaeological sites. This work explores the possibilities of multicomponent geophysical techniques in revealing antiquities that have been submerged in diverse shallow coastal marine environments in the eastern Mediterranean. A group of four sites in Greece (Agioi Theodoroi, Olous, Lambayanna) and Cyprus (Pafos) spanning from prehistory to Roman times were chosen as test sites to validate the efficiency of electrical resistivity tomography, magnetic gradiometry, and ground penetrating radar methods. The comprehensive analysis of the geophysical data completed the picture for the hidden archeological elements in all the sites. The results manifest the significance and the potential of these methods for documenting and understanding the complex archaeological sites encountered in the Mediterranean. In view of climate change and the risks related to future sea level rise and erosion of low-level coastal areas, the results of this work could be integrated in a strategic framework to develop an effective interdisciplinary research model that can be applied to similar shallow water archaeological surveys, thus substantially contributing towards cultural resources management.

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The first occurrence of the enigmatic archosaur Crosbysaurus (Heckert 2004) from the Chinle Formation of Southern Utah

10.7287/peerj.preprints.537v2 ◽

2014 ◽

Author(s):

Robert J Gay ◽

Isabella St. Aude

Keyword(s):

New Mexico ◽

Close Association ◽

First Record ◽

Geographic Range ◽

Type Locality ◽

Late Triassic ◽

Southern Area ◽

Chinle Formation ◽

First Occurrence ◽

Unique Compound

Originally identified as an ornithisichian dinosaur, Crosbysaurus has been found in New Mexico, Arizona, and the type locality in Texas. The genus has been reassessed by other workers in light of revelations about the postcrania of another putative Triassic ornithischian, Revueltosaurus. The understanding of Triassic dental faunas has become more complicated by the extreme convergence between pseudosuchian archosaurus and ornithichian dinosaur dental morphologies. We report here on a new specimen of Crosbysaurus from the Petrified Forest Member of the Chinle Formation at Comb Ridge in southeastern Utah. This new specimen is assigned to Crosbysaurus on the basis of the unique compound posterior denticles, mediolateral width, and curvature. While this specimen, MNA V10666, does not help resolve the affinities of Crosbysaurus it does represent an approximately 250 kilometer extension of the geographic range of this taxon. This is the first record of this taxon in Utah and as such it represents the northernmost known record of Crosbysaurus. This indicates that Crosbysaurus was not limited to the southern area of Chinle/Dockum deposition but instead was widespread across the paleoriver systems of the Late Triassic in western Pangea. The specimen we report on here was found in close association with a typical Late Triassic Chinle fauna, including phytosaurs, metoposaurs, and dinosauromorphs.

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T. H. Blackburn & J. Sørensen editors. Nitrogen Cycling in Coastal Marine Environments, xxv, 451 pp. John Wiley, 1988. Price £55.00.

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531540004340x ◽

1988 ◽

Vol 68 (3) ◽

pp. 547-547

Keyword(s):

Nitrogen Cycling ◽

Marine Environments ◽

Coastal Marine

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The pre-Hispanic history of Mexican California. The road to Mesoamerica that was never completed

Latinskaia Amerika ◽

10.31857/s0044748x0015307-6 ◽

2021 ◽

pp. 69

Author(s):

Valentina Baglay

Keyword(s):

Geographical Isolation ◽

The Road ◽

Terrestrial Mammals ◽

The North ◽

Spiritual Culture ◽

History Of ◽

Rock Paintings

The article is devoted to the study of the oldest cultures of the California Peninsula. The analysis is based on the study of archaeological monuments of material and spiritual culture, reflected in rock paintings, petroglyphs and geoglyphs. The first traces of settlers in the territory of Mexican California are about 14,000 years old (Clovis culture) and are associated with Aridoamerica. Cultures have been coming in from the north continuously, although their sequence has yet to be determined. A culture of nomadic and semi-nomadic groups (the conchero camp culture) was formed here, collecting shellfish, plants and fruits, coastal fishing, and hunting marine and terrestrial mammals. The geographical isolation of the peninsula did not allow the establishment of links between Californians and Mesoamerican cultural areas.

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Quaternary Climatic Changes and Landscape Evolution

The Physical Geography of Western Europe ◽

10.1093/oso/9780199277759.003.0012 ◽

2005 ◽

Author(s):

Jürgen Ehlers

Keyword(s):

Climatic Change ◽

Large Scale ◽

Western Europe ◽

Ice Sheets ◽

Climatic Changes ◽

Mountain Glaciers ◽

Marine Deposits ◽

The North ◽

Terrestrial Sediments ◽

International Geological Congress

The last 2–3 Ma have witnessed climatic changes of a scale unknown to the preceding 300 Ma. In the cold periods vegetation was reduced to a steppe, giving rise to large-scale aeolian deposition of sand and loess and river sands and gravels. In the warm stages, flora and fauna recolonized the region. Parts of Europe were repeatedly covered by mountain glaciers or continental ice sheets which brought along huge amounts of unweathered rock debris from their source areas. The ice sheets dammed rivers and redirected drainage towards the North Sea. They created a new, glacial landscape. This chapter presents an outline of the climatic history, and in particular the glacial processes involved in shaping the landscapes of western Europe. By convention, geologists generally tend to draw stratigraphical boundaries in marine deposits because they are more likely to represent continuous sedimentation and relatively consistent environments in comparison to terrestrial sediments. However, marine deposits from the period in question are relatively rarely exposed at the surface. According to a conclusion of the International Geological Congress 1948 the Tertiary/Quaternary boundary was defined as the base of the marine deposits of the Calabrian in southern Italy. In the Calabrian sediments fossils are found that reflect a very distinct climatic cooling (amongst others the foraminifer Hyalinea baltica). This climatic change roughly coincides with a reversal of the earth’s magnetic field; it is situated at the upper boundary of what is called the Olduvai Event. Consequently, it is relatively easy to identify; its age is today estimated at 1.77 Ma (Shackleton et al. 1990). However, in contrast to the older parts of the earth’s history, the significant changes within the Quaternary are not changes in faunal composition but changes in climate. For reasons of long-term climatic evolution the base of the Calabrian is not a very suitable global boundary. Its adoption excludes some of the major glaciations from the Quaternary. Therefore, in major parts of Europe another Tertiary/Quaternary boundary is in use, based on the stratigraphy of the Lower Rhine area (e.g. Zagwijn 1989). Here the most significant climatic change is already recorded as far back as the Gauss/Matuyama magnetic reversal (some 2.6 Ma ago).

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Stratigraphy and timing of eolianite deposition on Rottnest Island, Western Australia

Quaternary Research ◽

10.1016/s0033-5894(03)00063-2 ◽

2003 ◽

Vol 60 (2) ◽

pp. 211-222 ◽

Cited By ~ 26

Author(s):

Paul J. Hearty

Keyword(s):

North Atlantic ◽

Late Quaternary ◽

The West ◽

Oxygen Isotope Stage ◽

Amino Acid Racemization ◽

Marine Deposits ◽

The North ◽

The North Atlantic ◽

Radiometric Ages ◽

Mis 5E

AbstractOver 100 whole-rock amino acid racemization (AAR) ratios from outcrops around Rottnest Island (32.0° S Latitude near Perth) indicate distinct pulses of eolian deposition during the late Quaternary. Whole-rock d-alloisoleucine/l-isoleucine (A/I) ratios from bioclastic carbonate deposits fall into three distinct modal classes or “aminozones.” The oldest, Aminozone E, averages 0.33 ± 0.04 (n = 21). Red palaeosol and thick calcrete generally cap the Aminozone E deposits. A younger Aminozone C averages 0.22 ± 0.03 (n = 63); comprising two submodes at 0.26 ± 0.01 (n = 14) and 0.21 ± 0.02 (n = 49). Multiple dune sets of this interval are interrupted by relatively weak, brown to tan “protosols.” A dense, dark brown rendzina palaeosol caps the Aminozone C succession. Ratios from Holocene dune and marine deposits (“Aminozone A”) center on 0.11 ± 0.02 (n = 15), comprising submodes of 0.13 ± 0.01 (9) and 0.09 ± 0.01 (6). Calibration of A/I averages from Aminozones E and A are provided by U/Th and 14C radiometric ages of 125,000 yr (marine oxygen isotope stage (MIS) 5e and 2000–6000 14C yr B.P. (MIS 1), respectively. The whole-rock A/I results support periodic deposition initiated during MIS 5e, continuing through MIS 5c, and then peaking at the end of MIS 5a, about 70,000–80,000 yr ago. Oceanographic evidence indicates the area was subjected to much colder conditions during MIS 2–4 (10,000 to 70,000 yr ago), greatly slowing the epimerization rate. Eolianite deposition resumed in the mid Holocene (∼6000 yr ago) up to the present. The A/I epimerization pathway constructed from Rottnest Island shows remarkable similarity to that of Bermuda in the North Atlantic (32° N Latitude). These findings suggest that, like Bermuda, the eolian activity on Rottnest occurred primarily during or shortly after interglacial highstands when the shoreline was near the present datum, rather than during glacial lowstands when the coastline was positioned 10–20 km to the west.

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