scholarly journals Late Miocene chondrichthyans from Lago Bayano, Panama: Functional diversity, environment and biogeography

2017 ◽  
Vol 91 (3) ◽  
pp. 512-547 ◽  
Author(s):  
Victor J. Perez ◽  
Catalina Pimiento ◽  
Austin Hendy ◽  
Gerardo González-Barba ◽  
Gordon Hubbell ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Functional Diversity ◽  
Late Miocene ◽  
Fossil Record ◽  
Marine Mammals ◽  
Probabilistic Approach ◽  
Generalist Species ◽  
The Pacific ◽  
Wide Range

AbstractThis newly described chondrichthyan fauna from the late Miocene Chucunaque Formation of Lago Bayano reveals a prolific and highly diverse assemblage from Panama, and one of the richest shark faunas from the Neotropics. Strontium geochronology indicates an age of 10–9.5 Ma for the chonrichthyan-bearing strata. Field efforts resulted in 1429 identifiable specimens comprising at least 31 taxa, of which at least eight are new to the documented fossil record of Panama. With this information an analysis of functional diversity was conducted, indicating ecosystems dominated by generalist species feeding upon a wide range of organisms, from plankton to marine mammals. A probabilistic approach of paleobathymetric estimation suggests a neritic environment. Previous studies based on foraminifera have suggested that the Chucunaque Formation had a greater Pacific Ocean affinity, making this the first Miocene chondrichthyan fauna described from the Pacific shelf of Panama. However, our geographic comparisons show that this fauna has mixed Caribbean and Pacific biogeographic affinities, which likely supports the previously purported connection between chondrichthyan faunas during the late Miocene.

Hardly Pacific

2015 ◽  
Vol 84 (1) ◽  
pp. 1-18 ◽  
Author(s):  
David Igler
Keyword(s):  
Nineteenth Century ◽  
Pacific Ocean ◽  
Marine Mammals ◽  
American Culture ◽  
Indigenous Communities ◽  
Gold Rush ◽  
Violent Death ◽  
The West ◽  
The Pacific ◽  
The Pacific Ocean

American culture has long associated the nineteenth-century U.S. frontier with episodes of violent death and random bloodshed. But what about the vast watery expanse west of the West? The Pacific Ocean contains its own violent past, especially during the period stretching from Captain James Cook's historic voyages to the California Gold Rush. The nature and degree of this violence stemmed not merely from contact relations between indigenous communities and newcomers, but more specifically from commercial desires, the diffusion of diseases, and the great hunt for marine mammals. Historicizing this violent past remains an imperative for new studies of the Pacific.

scholarly journals The first fossil parrot (Aves, Psittaciformes) from Siberia and its implications for the historical biogeography of Psittaciformes

2016 ◽  
Vol 12 (10) ◽  
pp. 20160717 ◽  
Author(s):  
Nikita V. Zelenkov
Keyword(s):  
Pacific Ocean ◽  
Geographical Distribution ◽  
Fossil Record ◽  
Historical Biogeography ◽  
Early Miocene ◽  
Baikal Lake ◽  
The Past ◽  
The Pacific ◽  
The Pacific Ocean ◽  
Climatic Optimum

Modern parrots (crown Psittaciformes) are a species-rich group of mostly tropical and subtropical birds with a very limited fossil record. A partial tarsometatarsus from the late Early Miocene of Siberia (Baikal Lake) is the first pre-Quaternary find of crown Psittaciformes in Asia (and Siberia in particular) and is also the northern-most find of this bird order worldwide. This find documents a broad geographical distribution of parrots during the warmest phase of the Miocene (the so-called ‘Miocene Climatic Optimum’), which has implications for the historical biogeography of Psittaciformes. The presence of parrots on both sides of the Pacific Ocean at the end of the Early Miocene implies a (most probably eastwards) trans-Beringian dispersal which likely took place about 16–18 Ma. The broad Eurasian distribution of parrots in the past further supports a hypothesis that ancestors of modern genera Coracopsis and Agapornis could reach Africa from Eurasia.

scholarly journals Clinical report of a human bite by the pelagic sea snake Hydrophis Platurus (Serpentes: Elapidae), in the pacific ocean of Costa Rica

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Viviana Ramos-Rodríguez ◽  
◽  
Earvin Montero-Carvajal ◽  
Greivin Corrales ◽  
Aarón Gómez ◽  
...  
Keyword(s):  
Costa Rica ◽  
Pacific Ocean ◽  
Clinical Symptoms ◽  
Snake Bite ◽  
Clinical Report ◽  
Sea Snake ◽  
Sea Snakes ◽  
The Pacific ◽  
Wide Range ◽  
The Pacific Ocean

Introduction: The pelagic sea snake, “Serpiente Marina,” Hydrophis Platurus, shows a wide-range distribution in the Indo-Pacific Ocean, reaching the Pacific coast of the Americas. Although the snake bite accidents caused by sea snakes are rare, Costa Rica occasionally presents large quantities of sea snakes stranded in the shore, mainly during the dry season. Discussion: A 12-years-old boy was bitten in Playas del Coco, Sardinal, Guanacaste province, Costa Rica, and almost immediately started to develop pain and paresthesia. A coagulation time test was performed, although its importance is not relevant to the treatment of snakebite accidents caused by sea snakes, mainly due to its neurotoxic characteristics. Conclusion: Although there is no antivenom available to treat snakebite accidents from the pelagic seasnake, its treatment is frequently misinterpreted, incurring in clinical tests that are not necessary and putting aside the tests that have more relevance to the potential clinical symptoms of the snake bite.

Sharks and rays (Chondrichthyes, Elasmobranchii) from the late Miocene Gatun Formation of Panama

2013 ◽  
Vol 87 (5) ◽  
pp. 755-774 ◽  
Author(s):  
Catalina Pimiento ◽  
Gerardo González-Barba ◽  
Dana J. Ehret ◽  
Austin J. W. Hendy ◽  
Bruce J. MacFadden ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Shallow Water ◽  
Late Miocene ◽  
Habitat Preferences ◽  
Caribbean Sea ◽  
Shallow Waters ◽  
The Pacific ◽  
Dental Measurements ◽  
The Pacific Ocean ◽  
The Caribbean

The late Miocene Gatun Formation of northern Panama contains a highly diverse and well sampled fossil marine assemblage that occupied a shallow-water embayment close to a purported connection between the Pacific and Atlantic (Caribbean) oceans. However, the diverse chondrichthyan fauna has been poorly documented. Based on recent field discoveries and further analysis of existing collections, the chondrichthyan fauna from this unit comprises at least 26 taxa, of which four species are extinct today. The remaining portion of the total chondrichthyan biodiversity has affinities with modern taxa and is therefore comprised of long-lived species. Based on known records of the modern geographic distribution range of the Gatun chondrichthyans, the fauna has mixed biogeographic affinities suggesting that around 10 million yr ago, a connection likely occurred between the Pacific Ocean and the Caribbean Sea. Given the known habitat preferences for modern chondrichthyans, the Gatun fauna was primarily adapted to shallow waters within the neritic zone. Finally, comparisons of Gatun dental measurements with other faunas suggest that many of the taxa have an abundance of small individuals, in agreement with previous studies that proposed this area as a paleonursery habitat for the species Carcharocles megalodon.

scholarly journals Detecting the 11 March 2011 Tohoku tsunami arrival on sea-level records in the Pacific Ocean: application and performance of the Tsunami Early Detection Algorithm (TEDA)

2012 ◽  
Vol 12 (5) ◽  
pp. 1583-1606 ◽  
Author(s):  
L. Bressan ◽  
S. Tinti
Keyword(s):  
Pacific Ocean ◽  
Early Detection ◽  
Real Time ◽  
Sea Level ◽  
Detection Algorithm ◽  
2011 Tohoku Tsunami ◽  
The Pacific ◽  
Wide Range ◽  
The Pacific Ocean ◽  
Tohoku Tsunami

Abstract. Real-time detection of a tsunami on instrumental sea-level records is quite an important task for a Tsunami Warning System (TWS), and in case of alert conditions for an ongoing tsunami it is often performed by visual inspection in operational warning centres. In this paper we stress the importance of automatic detection algorithms and apply the TEDA (Tsunami Early Detection Algorithm) to identify tsunami arrivals of the 2011 Tohoku tsunami in a real-time virtual exercise. TEDA is designed to work at station level, that is on sea-level data of a single station, and was calibrated on data from the Adak island, Alaska, USA, tide-gauge station. Using the parameters' configuration devised for the Adak station, the TEDA has been applied to 123 coastal sea-level records from the coasts of the Pacific Ocean, which enabled us to evaluate the efficiency and sensitivity of the algorithm on a wide range of background conditions and of signal-to-noise ratios. The result is that TEDA is able to detect quickly the majority of the tsunami signals and therefore proves to have the potential for being a valid tool in the operational TWS practice.

On the Pacific Ocean regime shift

2001 ◽  
Vol 28 (19) ◽  
pp. 3721-3724
Author(s):  
Cathy Stephens
Keyword(s):  
Pacific Ocean ◽  
Regime Shift ◽  
The Pacific ◽  
The Pacific Ocean
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