Changes in bivalve functional and assemblage ecology in response to environmental change in the Caribbean Neogene

Paleobiology ◽  
2012 ◽  
Vol 38 (4) ◽  
pp. 509-524 ◽  
Author(s):  
Jill S. Leonard-Pingel ◽  
Jeremy B. C. Jackson ◽  
Aaron O'Dea
Keyword(s):  
Functional Groups ◽  
Relative Abundance ◽  
Benthic Communities ◽  
Central American ◽  
Carbonate Content ◽  
The Past ◽  
Central American Seaway ◽  
The Caribbean ◽  
Response To Environmental Change ◽  
Deposit Feeding

We documented changes in the relative abundance of bivalve genera and functional groups in the southwest Caribbean over the past 11 Myr to determine their response to oceanographic changes associated with the closure of the Central American Seaway ca. 3.5 Ma. Quantitative bulk samples from 29 localities yielded 106,000 specimens in 145 genera. All genera were assigned to functional groups based on diet, relationship to the substrate, and mobility. Ordinations of assemblages based on quantitative data for functional groups demonstrated strong shifts in community structure, with a stark contrast between assemblages older than 5 Ma and those younger than 3.5 Ma. These changes are primarily due to an increase in the abundance of attached epifaunal bivalves (e.g., Chama, Arcopsis, and Barbatia) and a decrease in infaunal bivalves (e.g., Varicorbula and Caryocorbula). Taxa associated with seagrasses, including deposit-feeding and chemosymbiotic bivalves (e.g., Lucina), also increased in relative abundance compared to suspension feeders. The composition of bivalve assemblages is correlated with the carbonate content of sediments and the percentage of skeletal biomass that is coral. Our results strongly support the hypothesis that increases in the extent of coral reefs and Thalassia communities were important drivers of biologic turnover in Neogene Caribbean benthic communities.

Biogeography of Iberian Atlantic Neogene marginelliform gastropods (Marginellidae, Cystiscidae): global change and transatlantic colonization

2011 ◽  
Vol 85 (6) ◽  
pp. 1052-1066 ◽  
Author(s):  
Carlos Marques Da Silva ◽  
Bernard Landau ◽  
Rafael La Perna
Keyword(s):  
West Africa ◽  
Sea Water ◽  
Atlantic Coast ◽  
Central American ◽  
Marine Gastropods ◽  
High Productivity ◽  
Complex Process ◽  
Central American Seaway ◽  
Central Portugal ◽  
The Caribbean

The Marginellidae Fleming and the Cystiscidae Stimpson, herein collectively referred to as marginelliform gastropods, are convergent families of thermophilic marine gastropods. Shallow-water marginelliform gastropods are found in the Ibero-Moroccan Gulf and Mediterranean, diversity rapidly increasing towards tropical West Africa. Surprisingly, in the tropical and subtropical European Miocene fossil record, marginelliform genera of tropical affinity such asPersiculaSchumacher andPrunumHerrmannsen, occurring today in West Africa, are altogether missing. Others, such asMarginellaLamarck, are present only in the southwestern Iberian and Mediterranean Neogene record. This work describes the marginelliform gastropods from the Atlantic Iberian Neogene. Ten species are recorded, of which three are new,Persicula mikhailovaen. sp.,Gibberula costaen. sp., andGibberula brebionin. sp. This study shows thatGibberulaSwainson andVolvarinaHinds have been present in Europe since the Eocene.Marginellamay have originated in southern Africa and migrated north to Europe in the Miocene, never extending further north than west central Portugal.PersiculaandPrunumprobably originated in the Caribbean and migrated east during the Pliocene, following closure of the Central American Seaway. The colonization of the Pliocene European Atlantic coast by gastropods of these genera was selective, only where high sea-water temperature and high productivity were combined. These findings suggest that post-Messinian recolonization of the Mediterranean during the Pliocene was a complex process, involving colonization by groups originating in various regions of the Atlantic, including Europe, Africa and the Americas.

scholarly journals The search for an elusive worm in the tropics, the past as a key to the present, and reverse uniformitarianism

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Luis I. Quiroz ◽  
Luis A. Buatois ◽  
Koji Seike ◽  
M. Gabriela Mángano ◽  
Carlos Jaramillo ◽  
...  
Keyword(s):  
Pacific Coast ◽  
Cold Water ◽  
High Energy ◽  
Central American ◽  
The Past ◽  
The Pacific ◽  
The Caribbean ◽  
The Tropics ◽  
Oceanographic Conditions ◽  
Made In

AbstractThe distribution of trace-making organisms in coastal settings is largely controlled by changes in physicochemical parameters, which in turn are a response to different climatic and oceanographic conditions. The trace fossil Macaronichnus and its modern producers are typical of high-energy, siliciclastic foreshore sands in intermediate- to high-latitude settings characterized by cold-water conditions. However, it has been found in Miocene Caribbean deposits of Venezuela, prompting the hypothesis that upwelling of cold, nutrient-rich waters rather than latitude was the main control of its distribution. To test this hypothesis that was solely based on the fossil record, several trenches and sediment peels were made in two high-energy sand beaches having different oceanographic conditions along the Pacific and Caribbean coasts of the Central American Isthmus. As predicted, the burrows were found only in the highly productive waters of the Pacific coast of Costa Rica in connection with upwelling, while they were absent from the warm, oligotrophic waters of the Caribbean coast of Panama. This finding demonstrates that sometimes the past may be a key to the present, providing one of the few documented examples of reverse uniformitarianism.

USING HISTORICAL ANNUAL REPORTS IN TEACHING: LETTING THE PAST BENEFIT THE PRESENT

1992 ◽  
Vol 19 (1) ◽  
pp. 29-50 ◽  
Author(s):  
Joel Amernic ◽  
Ramy Elitzur
Keyword(s):  
Environmental Change ◽  
Cash Flow ◽  
Accounting Education ◽  
Annual Reports ◽  
The Past ◽  
Response To Environmental Change

In this article, it is suggested that accounting education may be enhanced by the use of published historical accounting materials, such as annual reports. Comparing such materials with modern reports serves to reinforce the notion that accounting evolves in response to environmental change. Further, requiring students to analytically derive cash flow statements from historical published annual reports provides several direct pedagogical benefits.

FLOW REVERSAL IN THE CENTRAL AMERICAN SEAWAY DURING OR AFTER THE OLIGOCENE MIOCENE TRANSITION

2017 ◽  
Author(s):  
Andrew Jeffrey Fraass ◽  
◽  
R. Mark Leckie ◽  
Christopher M. Lowery ◽  
Robert DeConto
Keyword(s):  
Flow Reversal ◽  
Central American ◽  
Central American Seaway

scholarly journals Unraveling the Gut Microbiome of the Invasive Small Indian Mongoose (Urva auropunctata) in the Caribbean

2021 ◽  
Vol 9 (3) ◽  
pp. 465
Author(s):  
Anne A. M. J. Becker ◽  
KC Hill ◽  
Patrick Butaye
Keyword(s):  
Relative Abundance ◽  
Gut Microbiome ◽  
Taxonomic Diversity ◽  
Caribbean Islands ◽  
Microbial Profile ◽  
Vegetation Zones ◽  
Males And Females ◽  
The Caribbean ◽  
Metabolic Properties ◽  
Small Indian Mongoose

Small Indian mongooses (Urva auropunctata) are among the most pervasive predators to disrupt the native ecology on Caribbean islands and are strongly entrenched in their areas of introduction. Few studies, however, have considered the microbial ecology of such biological invasions. In this study, we investigated the gut microbiota of invasive small Indian mongooses in terms of taxonomic diversity and functional potential. To this end, we collected fecal samples from 60 free-roaming mongooses trapped in different vegetation zones on the island Saint Kitts. The core gut microbiome, assessed by 16S rRNA amplicon gene sequencing on the Ion S5TM XL platform, reflects a carnivore-like signature with a dominant abundance of Firmicutes (54.96%), followed by Proteobacteria (13.98%) and Fusobacteria (12.39%), and a relatively minor contribution of Actinobacteria (10.4%) and Bacteroidetes (6.40%). Mongooses trapped at coastal sites exhibited a higher relative abundance of Fusobacterium spp. whereas those trapped in scrubland areas were enriched in Bacteroidetes, but there was no site-specific difference in predicted metabolic properties. Between males and females, beta-diversity was not significantly different and no sex-specific strategies for energy production were observed. However, the relative abundance of Gammaproteobacteria, and more specifically, Enterobacteriaceae, was significantly higher in males. This first description of the microbial profile of small Indian mongooses provides new insights into their bioecology and can serve as a springboard to further elucidating this invasive predator’s impact throughout the Caribbean.

An ecological shift in a remote coral atoll of Belize over 25 years

1998 ◽  
Vol 25 (2) ◽  
pp. 122-130 ◽  
Author(s):  
TIMOTHY R. McCLANAHAN ◽  
NYAWIRA A. MUTHIGA
Keyword(s):  
Central America ◽  
Major Change ◽  
Acropora Cervicornis ◽  
Hard Coral ◽  
Population Densities ◽  
Herbivorous Fishes ◽  
Patch Reefs ◽  
The Past ◽  
Algal Abundance ◽  
The Caribbean

Many coral reefs in the Caribbean, and elsewhere, have undergone changes from hard coral to fleshy algal dominance over the past two decades which has often been interpreted as a localized response to eutrophication and fishing. Here, data on the abundance of hard corals and algae from lagoonal patch reefs distributed throughout a large (260 km2) remote reef atoll located approximately 30 km offshore from the sparsely-populated coast of Belize, Central America, are compared with a study of these patch reefs conducted 25 years previously. Data and observations indicate that these patch reefs have undergone a major change in their ecology associated with a 75% reduction in total hard coral, a 99% loss in the cover of Acropora cervicornis and A. palmata, and a 315% increase in algae, which are mostly erect brown algae species in the genera Lobophora, Dictyota, Turbinaria and Sargassum. Such changes have been reported from other Caribbean reefs during the 1980s, but not on such a remote reef and the present changes may be attributed primarily to both a disease that began killing Acropora in this region in the mid 1980s and a reduction in herbivory. The low level of herbivory may be attributable to the disease-induced loss of the sea urchin Diadema antillarum in 1983, or fishing of herbivorous fishes, but both explanations are speculative. The present density of fisherfolk is low, and their efforts are not targetted at herbivorous fishes, and population densities of D. antillarum 14 years after the mortality are <1 individual per 1000 m2, but there is no comparative data from before the die off. There is, however, no indication that these major changes occurred on the fore reef, because A. palmata is abundant and erect algal abundance is low. We suggest that reported changes in other Caribbean reefs are not necessarily or exclusively influenced by local human factors such as localized intense eutrophication or fishing.

scholarly journals Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study

2014 ◽  
Vol 29 (12) ◽  
pp. 1214-1237 ◽  
Author(s):  
Patrik L. Pfister ◽  
Thomas F. Stocker ◽  
Johannes Rempfer ◽  
Stefan P. Ritz
Keyword(s):  
Ocean Circulation ◽  
Drake Passage ◽  
Central American ◽  
Neodymium Isotopes ◽  
Model Study ◽  
Central American Seaway

scholarly journals Radiocarbon Dating of Calcined Bones: Where Does the Carbon Come from?

Radiocarbon ◽  
2009 ◽  
Vol 51 (2) ◽  
pp. 601-611 ◽  
Author(s):  
A Zazzo ◽  
J-F Saliège ◽  
A Person ◽  
H Boucher
Keyword(s):  
Radiocarbon Dating ◽  
Tooth Enamel ◽  
Skeletal Remains ◽  
Archaeological Sites ◽  
Carbonate Content ◽  
The Past ◽  
Mineral Fraction ◽  
Different Temperatures ◽  
C Value ◽  
Paleodietary Reconstruction

Over the past decade, radiocarbon dating of the carbonate contained in the mineral fraction of calcined bones has emerged as a viable alternative to dating skeletal remains in situations where collagen is no longer present. However, anomalously low δ13C values have been reported for calcined bones, suggesting that the mineral fraction of bone is altered. Therefore, exchange with other sources of carbon during heating cannot be excluded. Here, we report new results from analyses on cremated bones found in archaeological sites in Africa and the Near East, as well as the results of several experiments aiming at improving our understanding of the fate of mineral and organic carbon of bone during heating. Heating of modern bone was carried out at different temperatures, for different durations, and under natural and controlled conditions, and the evolution of several parameters (weight, color, %C, %N, δ13C value, carbonate content, crystallinity indexes measured by XRD and FTIR) was monitored. Results from archaeological sites confirm that calcined bones are unreliable for paleoenvironmental and paleodietary reconstruction using stable isotopes. Experimental results suggest that the carbon remaining in bone after cremation likely comes from the original inorganic pool, highly fractionated due to rapid recrystallization. Therefore, its reliability for 14C dating should be seen as close to that of tooth enamel, due to crystallographic properties of calcined bones.

Identification of Tropical Cyclones’ Critical Positions Associated with Extreme Precipitation Events in Central America

2021 ◽  
Author(s):  
Hugo G. Hidalgo ◽  
Eric J. Alfaro ◽  
Franklin Hernández-Castro ◽  
Paula M. Pérez-Briceño
Keyword(s):  
Central America ◽  
Tropical Cyclones ◽  
Critical Path ◽  
Central American ◽  
Pacific Basin ◽  
Extreme Precipitation Events ◽  
The Pacific ◽  
The Caribbean ◽  
Indirect Impacts ◽  
Precipitation Events

&lt;p&gt;Tropical cyclones are one of the most important causes of disasters in Central America. Using historical (1970&amp;#8211;2010) tracks of cyclones in the Caribbean and Pacific basin, we identify critical path locations where these low-pressure systems cause the highest number of floods in a set of 88 precipitation stations in the region. Results show that tropical cyclones from the Caribbean and Pacific basin produce a large number of indirect impacts on the Pacific slope of the Central American isthmus. Although the direct impact of a tropical cyclone usually results in devastation in the affected region, the indirect effects are more common and sometimes equally severe. In fact, the storm does not need to be an intense hurricane to cause considerable impacts and damage. The location of even a lower intensity storm in critical positions of the oceanic basin can result in destructive indirect impacts in Central America. The identification of critical positions can be used for emergency agencies in the region to issue alerts of possible flooding and catastrophic events.&lt;/p&gt;

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