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Uhen M.D.,George Mason University | Pyenson N.D.,Smithsonian Institution | Devries T.J.,Burke Museum of Natural History and Culture | Urbina M.,Museo de Historia Natural de San Marcos | And 2 more authors.
Journal of Paleontology | Year: 2011

Three new specimens of middle Eocene cetaceans are reported from the Pisco Basin of southern Peru. All three specimens originate from the Paracas Formation and their minimum age is constrained to about 37 Ma using 40Ar/ 39Ar dating of ash collected ∼100 m up section from the source localities. Two new genera of archaeocete cetaceans are described along with additional material of another distinctive protocetid, which is not named pending the discovery of more complete material. Phylogenetic analysis resolves the two new genera within Basilosauridae, while the unnamed protocetid is closely related to Eocetus. The discovery of crownward protocetids in South America demonstrates that early cetaceans may have dispersed into both hemispheres prior to evolving a fully aquatic lifestyle. Geochronologic constraints on the age of new Peruvian archaeocetes establish them as the oldest whales from South America and among the oldest known from the Southern Hemisphere, which highlights the need for better sampling of marginal marine rocks from this part of the world. © 2011 The Paleontological Society. Source


Taylor A.K.,University of Washington | Stein J.K.,Burke Museum of Natural History and Culture | Jolivette S.A.E.,University of Washington
Journal of Island and Coastal Archaeology | Year: 2011

In this article we examine prehistoric coastal settlement patterns in the San Juan Islands, Washington by integrating dating work with erosion studies, accumulation rate analysis, and paleoenvironmental data. Dating work draws on previously published radiocarbon dates from big sites and new radiocarbon dates from both big and small sites. We find that an increase in abundance of sites at 650-300 cal BP is amplified but not created by site destruction caused by coastal erosion. We hypothesize that prehistoric peoples established more permanent settlements on the San Juan Islands after 650 cal BP during a wetter climate regime. By calculating accumulation rates for shell midden sites and considering climate change and access to freshwater, we test this hypothesis and discuss differences between temporal patterns in the San Juan Islands and southwestern British Columbia. © 2011 Taylor & Francis Group, LLC. Source


News Article
Site: http://phys.org/biology-news/

The whale, named Fucaia buelli by the researchers, is transitional between ancient toothed whales and the baleen whales of modern seas. It is one of the oldest baleen whales ever found and, at a length of about 2-2.5m, also one of the smallest. The fossil, which was recovered from Olympic Peninsula, Washington State, USA, is described in a newly published paper in the UK journal Royal Society Open Science. Paper co-author Dr Felix Marx says that unlike its living baleen whale relatives, which use comb-like baleen plates to filter krill from the surrounding water, Fucaia had well-developed teeth which it used to actively hunt and chew its prey. "Once captured, prey was likely sucked deeper into the mouth for swallowing—a technique which, ultimately, may have given rise to baleen and filter feeding in the modern Mysticeti suborder of whales," Dr Marx says. Dr Marx and his co-authors Dr C.H. Tsai and Professor Ewan Fordyce say that the fossil sheds new light on one of the big questions in mammalian evolution; how, when and why did modern baleen whales lose their teeth? The complex teeth in Fucaia, and distinctive wear patterns, show that Fucaia likely chewed its food. Long-based and closely-spaced teeth in the jaw leave little room for baleen, but there are some indications that Fucaia perhaps had enlarged gums. "We think that Fucaia was similar to modern dolphins in capturing its prey using its teeth and perhaps strong suction. Suction feeding likely enabled early whales to move from a tooth-based feeding style to filter-feeding, by allowing them to capture smaller prey items than teeth alone could handle," Dr Marx says. The researchers note that suction feeding can still be seen in living grey whales. "This behaviour may have prompted the evolution of baleen from the enlarged gums, possibly as a more efficient way to expel the water sucked in with the food. As the prey became smaller, teeth became increasingly obsolete and, ultimately, were lost completely in modern baleen whales," says Professor Fordyce. What is it? A fossil partial skull, teeth, and associated skeleton of a small toothed whale, estimated 2-2.5 m long. This tiny whale was an adult individual, judging from fused bones in the skeleton. The species is new to science, and is named Fucaia buelli. Fucaia is named after the Strait of Juan da Fuca, in honour of its origin along the shores of those waters. Its second name, buelli, honours the exceptional illustrations of extinct whales produced by palaeo-artist Carl Buell. Fucaia belongs in a well-known extinct group, the family Aetiocetidae. (There is no common name for that group, but the meaning is roughly "beginning whale.") Such animals are transitional between toothed archaic whales and modern baleen whales. The specimen is from the Burke Museum of Natural History and Culture, at the University of Washington, Seattle, Washington, USA. Fucaia was probably an active hunter. It may have used suction to "vacuum" small prey into its mouth. Wear patterns on the teeth indicate that Fucaia used its teeth to secure and chew its food. The small body size suggests that the species had a limited range, and did not migrate like the large whales of modern oceans. The single known specimen of Fucaia buelli is from a shoreline outcrop on the north coast of the Olympic Peninsula, Washington State. Fucaia buelli lived early in Oligocene times, some 33-31 million years ago. At that time, the region that is now Olympic Peninsula was under-sea. At a global scale, this was a time of climate change. The earth changed from warm and even tropical "greenhouse" conditions to cooler "icehouse" conditions which saw ice-caps develop on Antarctica. The fossil was recovered as a cemented boulder (or concretion), by James L. Goedert and Bruce Crowley of the Burke Museum, University of Washington. Goedert is a well-known fossil collector, with many important finds to his credit. In the lab, the fossil was extracted from its surrounding matrix using pneumatic chisels and dilute acid. The preparation was carried out at the Burke Museum, University of Washington, and at the University of Otago, Dunedin, New Zealand. All the participating scientists are carrying out research on fossils to help understand the history of whales and dolphins. This study is one of several studies based on whale and dolphin fossils of the Burke Museum, University of Washington. Explore further: Researcher finds missing link between ancient toothed whales and modern baleen whales More information: Marx FG, Tsai C-H, Fordyce RE. 2015 A new Early Oligocene toothed 'baleen' whale (Mysticeti: Aetiocetidae) from western North America: one of the oldest and the smallest. Royal Society Open Science 2: 150476. dx.doi.org/10.1098/rsos.150476


Mckenna M.F.,University of California at San Diego | Cranford T.W.,San Diego State University | Berta A.,Smithsonian Institution | Pyenson N.D.,Burke Museum of Natural History and Culture
Marine Mammal Science | Year: 2012

Abstract: Toothed whales (crown Odontoceti) are unique among mammals in their ability to echolocate underwater, using specialized tissue structures. The melon, a structure composed of fat and connective tissue, is an important component in the production of an echolocation beam; it is known to focus high frequency, short duration echolocation clicks. Here, we report on the morphology of the odontocete melon to provide a comprehensive understanding of melon structure across odontocete taxa. This study examined nine odontocete species (12 individual specimens), from five of the ten extant odontocete families. We established standardized definitions using computed tomography scans of the melon to investigate structure without losing geometric integrity. The morphological features that relate to the focusing capacity of the melon include internal density topography, melon size and shape, and relationship to other forehead structures. The potential for melon structure to act as a filter is discussed: establishing a lower limit to the frequency of sounds that can be propagated through the head. Collectively, the results of this study provide a robust, quantitative and comparative framework for evaluating tissue structures that form a key component of the echolocation apparatus. © 2011 by the Society for Marine Mammalogy. Source


Kaye T.G.,Burke Museum of Natural History and Culture | Falk A.R.,Southwestern Oklahoma State University | Pittman M.,University of Hong Kong | Sereno P.C.,University of Chicago | And 5 more authors.
PLoS ONE | Year: 2015

Fluorescence using ultraviolet (UV) light has seen increased use as a tool in paleontology over the last decade. Laser-stimulated fluorescence (LSF) is a next generation technique that is emerging as a way to fluoresce paleontological specimens that remain dark under typical UV. A laser's ability to concentrate very high flux rates both at the macroscopic and microscopic levels results in specimens fluorescing in ways a standard UV bulb cannot induce. Presented here are five paleontological case histories that illustrate the technique across a broad range of specimens and scales. Novel uses such as back-lighting opaque specimens to reveal detail and detection of specimens completely obscured by matrix are highlighted in these examples. The recent cost reductions in medium-power short wavelength lasers and use of standard photographic filters has now made this technique widely accessible to researchers. This technology has the potential to automate multiple aspects of paleontology, including preparation and sorting of microfossils. This represents a highly cost-effective way to address paleontology's preparatory bottleneck. © 2015 Kaye et al.2015 Kaye et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Source

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