scholarly journals Still slow, but even steadier: an update on the evolution of turtle cranial disparity interpolating shapes along branches

2017 ◽  
Vol 4 (11) ◽  
pp. 170899 ◽  
Author(s):  
Christian Foth ◽  
Eduardo Ascarrunz ◽  
Walter G. Joyce
Keyword(s):  
Environmental Changes ◽  
Geometric Morphometric ◽  
Original Dataset ◽  
Branch Lengths ◽  
Apparent Correlation ◽  
Extinction Event ◽  
Extinction Events ◽  
A Minor ◽  
The Impact ◽  
Early Cenozoic

In a previous study, we estimated the cranial disparity of turtles (Testudinata) through time using geometric morphometric data from both terminal taxa and hypothetical ancestors to compensate for temporal gaps in the fossil record. While this method yielded reasonable results for the Mesozoic and the early Cenozoic, we found a large drop in cranial disparity for the Miocene, for which we found no correlation with known environmental changes or extinction events. Instead, we speculated that the Miocene dip was a result of poor sampling of fossils or ancestors in this time bin. To countervail this problem, we here updated our original dataset and interpolated changes of shape along the branch lengths and compared them with the previous data. We furthermore explored the impact of topological and temporal uncertainty, demonstrating that the Miocene dip, indeed, is a sampling artefact. All remaining conclusions of the previous study could be more or less supported, nevertheless, including an apparent correlation with global biogeographic events, a minor correlation between cranial disparity and global temperature, and resilience across the K/T extinction event.

Rapid and intense CO2 emissions into the atmosphere: Examples from the end-Triassic extinction

2020 ◽  
Author(s):  
Manfredo Capriolo ◽  
Benjamin Mills ◽  
Robert Newton ◽  
Jacopo Dal Corso ◽  
Alexander Dunhill ◽  
...  
Keyword(s):  
Industrial Revolution ◽  
Environmental Changes ◽  
Global Scale ◽  
Biogeochemical Model ◽  
Earth Planet ◽  
Central Atlantic Magmatic Province ◽  
Igneous Provinces ◽  
Extinction Events ◽  
Central Atlantic ◽  
The Impact

<p>The coincidence between mass extinction events and the emplacement of Large Igneous Provinces (LIPs) in the Phanerozoic geological record points to the magmatic CO<sub>2</sub> degassing as the potential trigger of rapid global-scale climatic and environmental changes. The Central Atlantic Magmatic Province (CAMP) is one of the Earth’s hugest LIPs, and is coincident with the end-Triassic extinction, at ca. 201.5 Ma. Such LIPs emplacement and associated magmatic CO<sub>2</sub> degassing have traditionally been interpreted as occurring over periods much longer than those of anthropogenic CO<sub>2</sub> emissions, however our improving understanding of LIPs activity is reducing these timescales, with the latest estimates indicating CAMP magmatic pulses lasting approximately a few centuries each and characterized by high eruption rates [1; 2]. We employed a biogeochemical model to investigate the effects on ocean-atmosphere system and climate of these CAMP magmatic pulses, and to test whether such rapid and intense magmatic CO<sub>2</sub> degassing is consistent with the climatic, geochemical and palaeontological record of the end-Triassic. Hence, we compared the modern anthropogenic emissions (since the Industrial Revolution) with the pulsed magmatic degassing during CAMP emplacement, in order to evaluate the impact of rapid and intense events on climate and environment changes.</p><p> </p><p>[1] Knight <em>et al.</em> (2004), <em>Earth Planet. Sci. Lett.</em> <strong>228</strong>, 143-160. [2] Marzoli <em>et al.</em> (2019), <em>J. Petrol.</em> <strong>60</strong>, 945-996.</p>

Rapid macrobenthic diversification and stabilization after the end-Cretaceous mass extinction event

Geology ◽  
2020 ◽  
Vol 48 (11) ◽  
pp. 1048-1052
Author(s):  
Francisco J. Rodríguez-Tovar ◽  
Christopher M. Lowery ◽  
Timothy J. Bralower ◽  
Sean P.S. Gulick ◽  
Heather L. Jones
Keyword(s):  
Mass Extinction ◽  
Rapid Recovery ◽  
Community Recovery ◽  
Scientific Drilling ◽  
Extinction Event ◽  
Chicxulub Impact Crater ◽  
Mass Extinction Event ◽  
International Ocean Discovery Program ◽  
Extinction Events ◽  
The Impact

Abstract Previous ichnological analysis at the Chicxulub impact crater, Yucatán Peninsula, México (International Ocean Discovery Program [IODP]/International Continental Scientific Drilling Program [ICDP] Site M0077), showed a surprisingly rapid initial tracemaker community recovery after the end-Cretaceous (Cretaceous-Paleogene [K-Pg]) mass extinction event. Here, we found that full recovery was also rapid, with the establishment of a well-developed tiered community within ∼700 k.y. Several stages of recovery were observed, with distinct phases of stabilization and diversification, ending in the development of a trace fossil assemblage mainly consisting of abundant Zoophycos, Chondrites, and Planolites, assigned to the Zoophycos ichnofacies. The increase in diversity is associated with higher abundance, larger forms, and a deeper and more complex tiering structure. Such rapid recovery suggests that favorable paleoenvironmental conditions were quickly reestablished within the impact basin, enabling colonization of the substrate. Comparison with the end-Permian extinction reveals similarities during recovery, yet postextinction recovery was significantly faster after the K-Pg event. The rapid recovery has significant implications for the evolution of macrobenthic biota after the K-Pg event. Our results have relevance in understanding how communities recovered after the K-Pg impact and how this event differed from other mass extinction events.

scholarly journals Differential human impact on the survival of genetically distinct avian lineages

1999 ◽  
Vol 9 (2) ◽  
pp. 147-154 ◽  
Author(s):  
Austin L. Hughes
Keyword(s):  
Human Impact ◽  
Physical Environment ◽  
Mass Extinction ◽  
The Earth ◽  
Biotic Diversity ◽  
Extinction Event ◽  
Mass Extinction Event ◽  
Extinction Events ◽  
The Impact ◽  
Mass Extinction Events

SummaryAt the present time the earth is facing an anthropogenic (human-caused) mass extinction event that may eventually rival previous mass extinction events caused by drastic changes i n the physical environment; however, the impact of this event on the earth's biotic diversity remains difficult to predict. Patterns of extinction and endangerment in birds, one of the best known taxonomically among major groups of organisms, showed that the distribution of human impact has been non-uniform relative to phylogenetic relationships. Fifteen major avian lineages differed over 35-fold with respect to the frequency of historical extinction and over threefold with respect to frequency of current threat; and overall rates of both extinction and threat were significantly higher in non-passerine orders than in passerines. Moreover, among both passerines and non-passerines, the rate of historic extinction has been significantly higher for species in monotypic genera than for other species; and in passerines, the rate of current threat is significantly higher for species in monotypic genera than for other species. Thus, the anthropogenic extinction and threat to avian species has specifically targeted species that are phylogenetically and thus, presumably genetically, unique.

Cyclo and chemostratigraphic characteristics of the Middle Silurian in Gotland, Sweden

2020 ◽  
Author(s):  
Michiel Arts ◽  
Bradley Cramer ◽  
Mikael Calner ◽  
Christian Rasmussen ◽  
Alyssa Bancroft ◽  
...  
Keyword(s):  
High Resolution ◽  
Carbon Isotope ◽  
Time Interval ◽  
Carbon Isotope Excursion ◽  
Core Dataset ◽  
Extinction Event ◽  
Age Model ◽  
Extinction Events ◽  
A Minor ◽  
Age Constraints

<p>The cumulative work of geoscientists over the past decades has shown that the Silurian Period which was once thought as warm and climatically stable time interval is in fact punctuated by numerous paleoenvironmental perturbations or events. These Silurian events follow a similar pattern where a minor extinction event precedes a substantial carbon isotope excursion. Many theories have been brought forward to explain these events ranging from glaciations, to changes in precipitations patterns, ocean currents and ocean anoxia. Constraints on the duration and timing of these extinction events and subsequent positive carbon isotope excursions are weak, which hampers a full understanding of the processes at play.</p><p>The data from the Altajme core from Gotland, Sweden provides us with a unique opportunity to look at two of these climatic perturbations during the Silurian. The Altajme core spans both the Sheinwoodian Ireviken event and the Homerian Mulde event. The Altajme core dataset includes a litholog, high-resolution δ13C data, correlated bentonites with U-Pb dates and a high-resolution XRF core scan: important data required for and integrated stratigraphic study. The U-Pb-dated bentonites give us age constraints. The δ13C data in combination with the high resolution XRF scan gives us insights into the changes in the ocean before during and after the events, while the XRF is also used to build cyclostratigraphic age constraints for the events and for the whole core. This stratigraphic study will provide us with a palaeoclimatological insights to explain these two events and provide us with a cyclostratigraphy based age model for the Middle Silurian.</p>

scholarly journals Ecological Response of Plankton to Environmental Change – Thresholds for Extinction

2019 ◽  
Author(s):  
Christopher Lowery ◽  
Paul Bown ◽  
Andy Fraass ◽  
Pincelli Hull
Keyword(s):  
Environmental Change ◽  
Environmental Changes ◽  
Marine Biota ◽  
Calcareous Nannoplankton ◽  
Planktic Foraminifera ◽  
Water Column Stratification ◽  
Extinction Event ◽  
Extinction Events ◽  
The Relationship ◽  
Mass Extinction Events

Severe climatic and environmental changes are far more prevalent in Earth history than major extinction events, and the relationship between environmental change and extinction severity has important implications for the outcome of the ongoing anthropogenic extinction event. The response of mineralized marine plankton to environmental change offers an interesting contrast to the overall record of marine biota, which is dominated by benthic invertebrates. Here, we summarize changes in the species diversity of planktic foraminifera and calcareous nannoplankton over the Mesozoic-Cenozoic and that of radiolarians and diatoms over the Cenozoic. We find that, aside from the Triassic-Jurassic and Cretaceous-Paleogene mass extinction events, extinction in the plankton is decoupled from that in the benthos. Extinction in the plankton appears to be driven primarily by major climatic shifts affecting water column stratification, temperature, and, perhaps, chemistry. Changes that strongly affect the benthos, like acidification and anoxia, have little effect on the plankton, or are associated with radiation.

scholarly journals The Sixth Species Extinction Event by Humans

2015 ◽  
Vol 5 (1) ◽  
pp. 61-72
Author(s):  
Victor John Nazarevich
Keyword(s):  
Mass Extinction ◽  
Recent Literature ◽  
Theoretical Research ◽  
Future Research ◽  
The Earth ◽  
Unknown Species ◽  
Extinction Event ◽  
Extinction Events ◽  
The Impact ◽  
The Relationship

The number of species becoming extinct has drawn a significant deal of attention from scientists and non-scientists alike. This research reviews recent literature citing evidence for the impact humans have had on our planet and how our biological systems are affected in both known species of flora and fauna as well as unknown species of flora and fauna, the latter lacking documentation as well as sightings by humans. Theoretical research is derived from previous research investigating the impacts of humankind’s use of the land as well as population increases. Though there are many different definitions of what a mass extinction is and gradations of extinction intensity, a conservative approach is used to assess the seriousness of the current ongoing extinction crisis, setting the highest level of recognition for mass extinction, in extreme diversity loss associated with the Big Five extinction events (Barnosky, 2011). Understanding the relationship between extinction and functional diversity over time will be critical for making conservation work (Boyer & Jetz, 2014). If another mass extinction is allowed to progress, it would mean the end of biodiversity as we know it and would also mean that greater pressure would be placed on both humans and flora and fauna to survive in a world completely changed by the Anthropocene. Over the course of 8,000-10,000 years, humans grew in population and changed the landscape of the Earth (Foley, 2013). The research concludes that focus should be on preserving the environment and future research should be performed on the study of unknown species.

Designing a CRM Framework for online & offline sports footwear retailers

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Rodrigo Cueva ◽  
Guillem Rufian ◽  
Maria Gabriela Valdes
Keyword(s):  
Environmental Changes ◽  
Customer Relationship ◽  
Business Strategies ◽  
Economic Sectors ◽  
Running Shoes ◽  
Brick And Mortar ◽  
Key Factor ◽  
On Line ◽  
The Impact

The use of Customer Relationship Managers to foster customers loyalty has become one of the most common business strategies in the past years.  However, CRM solutions do not fill the abundance of happily ever-after relationships that business needs, and each client’s perception is different in the buying process.  Therefore, the experience must be precise, in order to extend the loyalty period of a customer as much as possible. One of the economic sectors in which CRM’s have improved this experience is retailing, where the personalized attention to the customer is a key factor.  However, brick and mortar experiences are not enough to be aware in how environmental changes could affect the industry trends in the long term.  A base unified theoretical framework must be taken into consideration, in order to develop an adaptable model for constructing or implementing CRMs into companies. Thanks to this approximation, the information is complemented, and the outcome will increment the quality in any Marketing/Sales initiative. The goal of this article is to explore the different factors grouped by three main domains within the impact of service quality, from a consumer’s perspective, in both on-line and off-line retailing sector.  Secondly, we plan to go a step further and extract base guidelines about previous analysis for designing CRM’s solutions focused on the loyalty of the customers for a specific retailing sector and its product: Sports Running Shoes.

scholarly journals Quit Experiences among Primary Care Patients Enrolled in a Smoking Cessation Pilot RCT Early in the COVID-19 Pandemic

2021 ◽  
Vol 18 (3) ◽  
pp. 1011
Author(s):  
Andrea A. Joyce ◽  
Grace M. Styklunas ◽  
Nancy A. Rigotti ◽  
Jordan M. Neil ◽  
Elyse R. Park ◽  
...  
Keyword(s):  
Primary Care ◽  
Text Messaging ◽  
Risk Perceptions ◽  
Environmental Changes ◽  
Age Groups ◽  
Text Messages ◽  
Increased Risk ◽  
Primary Care Patients ◽  
The Impact ◽  
At Home

The impact of the COVID-19 pandemic on US adults’ smoking and quitting behaviors is unclear. We explored the impact of COVID-19 on smoking behaviors, risk perceptions, and reactions to text messages during a statewide stay-at-home advisory among primary care patients who were trying to quit. From May–June 2020, we interviewed smokers enrolled in a 12-week, pilot cessation trial providing text messaging and mailed nicotine replacement medication (NCT04020718). Twenty-two individuals (82% white, mean age 55 years), representing 88% of trial participants during the stay-at-home advisory, completed exit interviews; four (18%) of them reported abstinence. Interviews were thematically analyzed by two coders. COVID-19-induced environmental changes had mixed effects, facilitating quitting for some and impeding quitting for others. While stress increased for many, those who quit found ways to cope with stress. Generally, participants felt at risk for COVID-19 complications but not at increased risk of becoming infected. Reactions to COVID-19 and quitting behaviors differed across age groups, older participants reported difficulties coping with isolation (e.g., feeling disappointed when a text message came from the study and not a live person). Findings suggest that cessation interventions addressing stress and boredom are needed during COVID-19, while smokers experiencing isolation may benefit from live-person supports.

scholarly journals The intensity of slope and fluvial processes after a catastrophic windthrow event in small catchments in the Tatra Mountains

2021 ◽  
Vol 18 (6) ◽  
pp. 1405-1423
Author(s):  
Dariusz Strzyżowski ◽  
Elżbieta Gorczyca ◽  
Kazimierz Krzemień ◽  
Mirosław Żelazny
Keyword(s):  
Environmental Changes ◽  
Bedload Transport ◽  
Strong Wind ◽  
Tatra Mountains ◽  
Salvage Logging ◽  
Fluvial Processes ◽  
Wind Events ◽  
And Control ◽  
The Tatra Mountains ◽  
The Impact

AbstractStrong wind events frequently result in creating large areas of windthrow, which causes abrupt environmental changes. Bare soil surfaces within pits and root plates potentially expose soil to erosion. Absence of forest may alter the dynamics of water circulation. In this study we attempt to answer the question of whether extensive windthrows influence the magnitude of geomorphic processes in 6 small second- to third-order catchments with area ranging from 0.09 km2 to 0.8 km2. Three of the catchments were significantly affected by a windthrow which occurred in December 2013 in the Polish part of the Tatra Mountains, and the other three catchments were mostly forested and served as control catchments. We mapped the pits created by the windthrow and the linear scars created by salvage logging operations in search of any signs of erosion within them. We also mapped all post-windthrow landslides created in the windthrow-affected catchments. The impact of the windthrow on the fluvial system was investigated by measuring a set of channel characteristics and determining bedload transport intensity using painted tracers in all the windthrow-affected and control catchments. Both pits and linear scars created by harvesting tend to become overgrown by vegetation in the first several years after the windthrow. The only signs of erosion were observed in 10% of the pits located on convergent slopes. During the period from the windthrow event in 2013 until 2019, 5 very small (total area <100 m2) shallow landslides were created. The mean distance of bedload transport was similar (t-test, p=0.05) in most of the windthrow-affected and control catchments. The mapping of channels revealed many cases of root plates fallen into a channel and pits created near a channel. A significant amount of woody debris delivered into the channels influenced the activity of fluvial processes by creating alternating zones of erosion and accumulation.

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