Blog

4 PRIDE ESRs (S. Lazarev, E.L. Jorissen, S. van de Velde, L. Rausch) published a new paper in Quaternary Science Reviews (2019)

This new PRIDE research of ESRs, supervisors and partners on Pontocaspian magneto-biostratigraphic age constraints can be found here:

Magneto-biostratigraphic age constraints on the palaeoenvironmental evolution of the South Caspian basin during the Early-Middle Pleistocene (Kura basin, Azerbaijan)
by Sergei Lazarev, Elisabeth L. Jorissen, Sabrina van de Velde, Lea Rausch, Marius Stoica, Frank  P. Wesselingh, Christiaan G. C. Van Baak, Tamara  A. Yanina, Elmira Aliyeva, Wout Krijgsman
doi: 10.1016/j.quascirev.2019.105895

HIGHLIGHTS
• Akchagylian flooding of the Caspian Basin with mesohaline fauna is dated around 2.7–2.6 Ma.
• Regression in the Caspian Sea from 2.2 to 2.1 Ma is associated with new Apsheronian mollusc groups.
• FO of Apsheronian indicative molluscs is within the Reunion subchron at an age of ∼2.13 Ma.
• Faunal indications of periodical reconnections between the Caspian Sea and the Black Sea in the Apsheronian.
• The Apsheronian – Bakunian boundary is dated at 0.83–0.85 Ma.

The article can be found here

 

Sri Nandini defended her doctoral thesis

We are very happy to announce that Sri Nandini defended her doctoral thesis at the Univ. of Bremen on 10 Sept 2019. The title of the thesis is Hydroclimate variations in the Caspian Sea region in the late Quarternary to the Future. Congratulations, Sri!!!

Here you will find some pictures.

 

 

 

 

 

Our ESR Justine Vandendorpe has published new PRIDE research results (2019)

This new open-access PRIDE research can be found in the journal Ecology and Evolution:

Historical faunal exchange between the Pontocaspian Basin and North America
by Justine Vandendorpe, Christiaan G. C. van Baak, Björn Stelbrink, Diana Delicado, Christian Albrecht and Thomas Wilke
Ecology and Evolution (2019)
https://doi.org/10.1002/ece3.5602

ABSTRACT

Ecrobia is a genus of small brackish‐water mud snails with an amphi‐Atlantic distribution. Interestingly, the species occurring in the northwestern Atlantic, Ecrobia truncata, is more closely related to the Pontocaspian taxa, Ecrobia grimmi and Ecrobia maritima, than to the species occurring in the northeastern Atlantic and Mediterranean Sea. At least three colonization scenarios may account for this peculiar biogeographical pattern: (1) a recent human‐mediated dispersal, (2) a historical transatlantic interchange, and (3) a historical transpolar interchange. To test these three scenarios, we used five operational criteria—time of species divergence, first appearance in the fossil record, dispersal limitation as well as environmental filtering and biotic interactions along the potential migration routes. Specifically, we inferred a time‐calibrated molecular phylogeny for Ecrobia and reconstructed a paleogeographical map of the Arctic Ocean at 2.5 million years ago (Mya). Based on the five operational criteria, scenarios 1 and 2 can likely be rejected. In contrast, all criteria support scenario 3 (historical transpolar interchange). It is therefore suggested that a bird‐mediated and/or ocean current‐mediated faunal interchange via the Arctic Ocean occurred during the Late Pliocene or Early Pleistocene. This dispersal was likely facilitated by reduced distances between the Eurasian and North American/Greenland landmasses, marine introgressions, and/or a stepping‐stone system of brackish‐water habitats in northern Siberia, as well as a lack of competition along the migration route. As for the direction of dispersal, the scientific data presented are not conclusive. However, there is clearly more support for the scenario of dispersal from the Pontocaspian Basin to North America than vice versa. This is the first study providing evidence for a natural faunal exchange between the Pontocaspian Basin and North America via the Arctic Ocean.

The open-access article can be found here

PRIDE ESR Alexandre Gogaladze first author paper

This new open-access PRIDE research on Pontocaspian social networks can be found in the journal of bioRxiv

Social network analysis and the implications for Pontocaspian biodiversity conservation in Romania and Ukraine: A comparative study
by Aleksandre Gogaladze, Niels Raes, Koos Biesmeijer, Camelia Ionescu, Bianca Pavel, Mikhail O. Son, Natalia Gozak, Vitaliy Anistratenko and Frank P. Wesselingh
doi: https://doi.org/10.1101/740084

ABSTRACTRomania and Ukraine share the Black Sea coastline, the Danube Delta and associated habitats, which harbor the unique Pontocaspian biodiversity. Pontocaspian biota represents endemic aquatic taxa adapted to the brackish (anomalohaline) conditions, which evolved in the Caspian and Black Sea basins. Currently, this biota is diminishing both in the numbers of species and their abundance because of human activities. Consequently, its future persistence strongly depends on the adequacy of conservation measures. Romania and Ukraine have a common responsibility to effectively address the conservation of this biota. The socio-political and legal conservation frameworks, however, differ in the two countries - Romania is a member of the European Union (EU), thus complying with the EU environmental policy, whereas Ukraine is an EU-associated country. This may result in differences in the social network structure of stakeholder institutions with different implications for Pontocaspian biodiversity conservation. Here, we study the structure and implications of the social network of stakeholder organizations involved in conservation of Pontocaspian biodiversity in Romania, and compare it to Ukraine. We apply a mix of qualitative and quantitative social network analysis methods to combine the content and context of the interactions with relational measures. We show that the social networks of stakeholder organizations in Romania and Ukraine are very different. Structurally, in Romanian network there is a room for improvement through e.g. more involvement of governmental and non-governmental organizations and increased motivation of central stakeholders to initiate conservation action, whereas Ukrainian network is close to optimal. Regardless, both networks translate into sub-optimal conservation action and the road to optimal conservation is different. We end with sketching implications and recommendations for improved national and cross-border conservation efforts.

The open-access article can be found here

ESRs Elisabeth Jorissen and Sergei Lazarev published new PRIDE research

And again another PRIDE research article has been published! In the journal of Sedimentology you can now find the original manuscript of Elisabeth L. Jorissen, Sergei Lazarev and other PRIDE co-authors:

Amplitude, frequency and drivers of Caspian Sea lake‐level variations during the Early Pleistocene and their impact on a protected wave‐dominated coastline
by Elisabeth Jorissen, Hemmo Abels, Frank Wesselingh, Sergei Lazarev, Vusala Aghayeva and Wout Krijgsman
doi: 10.1111/sed.12658

ABSTRACTThe Caspian Sea, the largest isolated lake in the world, witnessed drastic lake‐level variations during the Quaternary. This restricted basin appears very sensitive to lake‐level variations, due to important variations in regional evaporation, precipitation and runoff. The amplitude, frequency and drivers of these lake‐level changes are still poorly documented and understood. Studying geological records of the Caspian Sea might be the key to better apprehend the complexity of these oscillations. The Hajigabul section documents sediment deposited on the northern margin of the Kura Basin, a former embayment of the Caspian Sea. The 2035 m thick, well‐exposed section was previously dated by magneto‐biostratigraphic techniques and provides an excellent record of Early Pleistocene environmental, lake‐level and climate changes. Within this succession, the 1050 m thick Apsheronian regional stage, between ca 2.1 and 0.85 Ma, represents a particular time interval with 20 regressive sequences documented by sedimentary and palaeontological changes. Sequences are regressing from offshore to coastal, lagoonal or terrestrial settings and are bounded by abrupt flooding events. Sediment reveals a low energy, wave‐dominated, reflective beach system. Wave baselines delimiting each facies association appear to be located at shallower bathymetries compared to the open ocean. Water depth estimations of the wave baselines allow reconstruction of a lake‐level curve, recording oscillations of ca 40 m amplitude. Cyclostratigraphic analyses display lake‐level frequency close to 41 kyr, pointing to allogenic forcing, dominated by obliquity cycles and suggesting a direct or indirect link with high‐latitude climates and environments. This study provides a detailed lake‐level curve for the Early Pleistocene Caspian Sea and constitutes a first step towards a better comprehension of the magnitude, occurrence and forcing mechanisms of Caspian Sea lake‐level changes. Facies models developed in this study regarding sedimentary architectures of palaeocoastlines affected by repeated lake‐level fluctuations may form good analogues for other (semi‐)isolated basins worldwide.

The open-access article can soon be found here

ESRs Sabrina van de Velde and Elisabeth L. Jorissen pusblished a new article in Biogeosciences (2019)

A new PRIDE article has been published! In open-access interactive journal Biogeosciences you can now find the article of Sabrina van de Velde and Elisabeth L. Jorissen and many PRIDE co-authors:

A conservation palaeobiological approach to assess faunal response of threatened biota under natural and anthropogenic environmental change
by Sabrina van de Velde, Elisabeth L. Jorissen, Thomas A. Neubauer, Silviu Radan, Ana Bianca Pavel, Marius Stoica, Christiaan G. C. Van Baak, Alberto Martínez Gándara, Luis Popa, Henko de Stigter, Hemmo A. Abels, Wout Krijgsman, and Frank P. Wesselingh
Biogeosciences, 16, 2423–2442 (2019)
https://doi.org/10.5194/bg-16-2423-2019

ABSTRACT
Palaeoecological records are required to test ecological hypotheses necessary for conservation strategies as short-term observations can insufficiently capture natural variability and identify drivers of biotic change. Here, we demonstrate the importance of an integrated conservation palaeobiology approach when making validated decisions for conservation and mitigating action. Our model system is the Razim–Sinoie lake complex (RSL) in the Danube Delta (Black Sea coast, Romania), a dynamic coastal lake system hosting unique Pontocaspian mollusc species that are now severely under threat. The Pontocaspians refer to an endemic species group that evolved in the Black Sea and Caspian Sea basins under reduced salinity settings over the past few million years. The natural, pre-industrial RSL contained a salinity gradient from fresh to mesohaline (18 ppm) until human intervention reduced the inflow of mesohaline Black Sea water into the lake system. We reconstruct the evolution of the RSL over the past 2000 years from integrated sedimentary facies and faunal analyses based on 11 age-dated sediment cores and investigate the response of mollusc species and communities to those past environmental changes. Three species associations (“marine”, “Pontocaspian” and “freshwater”) exist and their spatio-temporal shifts through the system are documented. Variable salinity gradients developed, with marine settings (and faunas) dominating in the southern part of the system and freshwater conditions (and faunas) in the northern and western parts. Pontocaspian species have mostly occurred in the centre of the RSL within the marine–freshwater salinity gradient. Today, freshwater species dominate the entire system, and only a single Pontocaspian species (Monodacna colorata) is found alive. We show that the human-induced reduced marine influence in the system has been a major driver of the decline of the endemic Pontocaspian biota. It urges improved conservation action by re-establishing a salinity gradient in the lake system to preserve these unique species.

The open-access article can be found here

Article published by ESRs Arthur F. Sands and Sergei Lazarev et al (2019)

We are happy to let you know that a new PRIDE article has been published in the Journal of Biogeography:

Contributions of biogeographical functions to species accumulation may change over time in refugial regions
by Arthur F. Sands, Sergej V. Sereda, Björn Stelbrink, Thomas A. Neubauer, Sergei Lazarev, Thomas Wilke and Christian Albrecht
Journal of Biogeography 46:1274–1286 (2019)
https://doi.org/10.1111/jbi.13590

Aim
Elevated biodiversity is the result of the cradle, museum or sink functions. The contributions of these three functions to species accumulation and their changes through time remain unknown for glacial refugia. Additionally, our understanding of the role these functions played during pre‐glacial periods is limited. We test for changes in contributions of functions through time leading to the current diversity patterns using a model refugium and taxon.

Location
Anatolia, Western Palaearctic.

Taxon
Freshwater neritid snails (genus Theodoxus).

The open-access article can be found here

New publication by ESRs Sabrina van de Velde et al (2019)

We are happy to let you know that a new PRIDE article has been published in the Journal of Great Lakes Research:

The Late Pleistocene mollusk fauna of Selitrennoye (Astrakhan province, Russia): A natural baseline for endemic Caspian Sea faunas
by Sabrina van de Velde, Tamara A.Yanin, Thomas A.Neubauer and Frank P. Wesselingh
 J. Great Lakes Res. 1–13, 2019
https://doi.org/10.1016/j.jglr.2019.04.001

ABSTRACT:

The native Caspian Sea fauna underwent severe changes since the early 20th century, mostly due to anthropogenic activities. However, the nature, magnitude and rate of biodiversity change can only be assessed by comparison with natural baseline settings. A mostly in-situ mollusk fauna retrieved from Late Pleistocene (Hyrcanian, 107 ± 7 ka) deposits at Selitrennoye (Astrakhan province, Russia) provides a snapshot of a natural Caspian assemblage. In total, 24 gastropod and 13 bivalve species were identified. The fauna is predominantly endemic/native (94% in species numbers and 99% in abundance) and is dominated by three families (Cardiidae, Dreissenidae and Hydrobiidae). The Selitrennoye assemblage is a natural baseline of a pre-invasive Caspian Sea fauna living in a shallow (15–25 m), lower mesohaline (5–8 psu) open lake environment. The species-rich Selitrennoye fauna contrasts with the largely depleted and invasive-dominated fauna that currently occupies similar habitats in the Caspian Sea and underlines the magnitude of the current biodiversity crisis.

Keywords
Pontocaspian; Biodiversity; Turnover; Extinction; Quaternary; Mollusca

The open-access article can be found here

New PRIDE research published by ESRs Thomas M. Hoyle & Manuel Sala-Pérez et al (2019)

We are happy to let you know that a new PRIDE article has been published in the Journal of Micropalaeontology:

Where should we draw the lines between dinocyst “species”? Morphological continua in Black Sea dinocysts
by Thomas M. Hoyle, Manuel Sala-Pérez, and Francesca Sangiorgi
J. Micropalaeontol., 38, 55–65, 2019
https://doi.org/10.5194/jm-38-55-2019

ABSTRACT:

The morphology of dinoflagellate cysts (dinocysts) is related not only to the genetics of the motile dinoflagellate from which it derives, but is also dependent on a range of environmental factors including salinity, temperature and nutrient status. Although this knowledge improves our understanding of the drivers behind dinocyst morphological variations, it makes the taxonomy governing their description somewhat complex. In basins such as the Black Sea, where environmental change can be extreme and occurs on relatively short (millennial) timescales, taxonomy becomes particularly challenging. Morphological continua can be observed between described forms, displaying a large range of intermediate phenotypes that do not necessarily correspond to any genetic difference. As these morphological nuances may preserve information about palaeoenvironments, it is important to find a systematic method of characterising morphotypes. Here, we show a dinocyst matrix within which dinocysts are described according to their similarity to (or difference from) described forms based on key descriptive parameters. In the example set out here, cyst shape and degree of process and/or ectophragm development are taken as two key parameters in Pyxidinopsis psilata and Spiniferites cruciformis, and can allow the description of intermediate forms even though the definitions do not overlap.

We review some frequently occurring morphotypes and propose that using matrices to show the gradual variation between endmember forms is the most pragmatic approach until cyst–theca studies and genetic sequencing can be used to demonstrate relationships between genotypes and morphotypes. As prior studies propose salinity to be a primary driver of intraspecific variability, the endmembers presented may represent salinity extremes within an overall brackish environment. Although we cannot assign each morphotype to a value or a range of an environmental parameter (e.g. salinity) as the different morphotypes can occur in the same sample, using this matrix allows preservation of information about morphological variability without creating taxonomic categories that are likely to require alteration if genetic evidence becomes available.

The open-access article can be found here

PRIDE article published by ESR Matteo Lattuada et al (2019)

We are pleased to let you know that a new article about PRIDE research has been published in Marine Pollution Bulletin:

Differential impact of anthropogenic pressures on Caspian Sea ecoregions
by Matteo Lattuada, Christian Albrecht and Thomas Wilke

ABSTRACT:

Over the past decades, overall ecological conditions in the Caspian Sea have deteriorated. However, a comprehensive understanding of lake-wide spatial differences in anthropogenic pressures is lacking and the biological consequences of human impacts are poorly understood. This paper therefore aims at assessing the individual and combined effects of critical anthropogenic pressures on the Caspian Sea ecoregions. First, cumulative pressure scores were calculated with a cumulative environmental assessment (CEA) analysis. Then, the individual contribution of anthropogenic pressures was quantified. Finally, ecoregion-specific differences were assessed. The analyses show that both cumulative and individual pressure scores are unevenly distributed across the Caspian Sea. The most important individual pressures are invasive species, chemical pollution and poaching. This uneven distribution of pressure scores across Caspian Sea ecoregions creates new challenges for future conservation strategies, as different ecoregions usually require different conservation measures.

The open-access article can be found here.

Mollusc species from the Pontocaspian region – an expert opinion list

Mollusc species from the Pontocaspian region – an expert opinion list

 
expand article infoFrank P. Wesselingh, Thomas A. Neubauer, Vitaliy V. Anistratenko, Maxim V. Vinarski, Tamara Yanina, Jan Johan ter Poorten, Pavel Kijashko, Christian Albrecht, Olga Yu. Anistratenko, Anouk D’Hont, Pavel Frolov, Alberto Martínez Gándara, Arjan Gittenberger, Aleksandre Gogaladze, Mikhail Karpinsky, Matteo Lattuada, Luis Popa, Arthur F. Sands, Sabrina van de Velde, Justine Vandendorpe, Thomas Wilke
 
https://doi.org/10.3897/zookeys.827.31365

Abstract

Defining and recording the loss of species diversity is a daunting task, especially if identities of species under threat are not fully resolved. An example is the Pontocaspian biota. The mostly endemic invertebrate faunas that evolved in the Black Sea – Caspian Sea – Aral Sea region and live under variable salinity conditions are undergoing strong change, yet within several groups species boundaries are not well established. Collection efforts in the past decade have failed to produce living material of various species groups whose taxonomic status is unclear. This lack of data precludes an integrated taxonomic assessment to clarify species identities and estimate species richness of Pontocaspian biota combining morphological, ecological, genetic, and distribution data. In this paper, we present an expert-working list of Pontocaspian and invasive mollusc species associated to Pontocaspian habitats. This list is based on published and unpublished data on morphology, ecology, anatomy, and molecular biology. It allows us to (1) document Pontocaspian mollusc species, (2) make species richness estimates, and (3) identify and discuss taxonomic uncertainties. The endemic Pontocaspian mollusc species richness is estimated between 55 and 99 species, but there are several groups that may harbour cryptic species. Even though the conservation status of most of the species is not assessed or data deficient, our observations point to deterioration for many of the Pontocaspian species.

Article published by Anouk D'Hont

We are happy to announce that Anouk D'Hont has published an article in the journal Aquatic Invasions, International Journal of Research on Biological Invasions in Aquatic Ecosystems:

Drivers of dominance shifts between invasive Ponto-Caspian dreissenids Dreissena polymorpha (Pallas, 1771) and Dreissena rostriformis bugensis (Andrusov, 1897), Anouk D’Hont, Adriaan Gittenberger, A. Jan Hendriks and Rob S.E.W. Leuven. You can find the article with this link:

Aquatic invasions 2018 issue 4

AGU Fall Meeting participation of our ESRs Sifan and Lea

Sifan A. Koriche and Lea Rausch presented their research at the Fall Meeting of the American Geophysical Union (AGU) held in Washington, DC, from December 9 – 14, 2018. The 51st AGU Fall Meeting was largest ever, with over 28,500 people coming to the capital of the US to share their science, forge connections, and enjoy the company of friends and colleagues. There were 101 countries represented, over 8000 oral presentations, 17,000 posters and 1,900 sessions.

Lea and Sifan are early stage researchers (ESRs) working under the framework of an ITN project funded by EU Horizon 2020 called PRIDE (the drivers of Pontocaspian biodiversity RIse and DEmise).

Lea gave a talk in the session “Advances in Paleoecology and Paleoclimate with Emphasis on Contextualizing Human Evolutionary History”. As part of an ecosystem, early humans played only a subordinate role in a much larger framework, consequently demanding a highly interdisciplinary approach to be able to understand the driving forces behind adaptive shifts in our evolutionary history. Within the framework of the PRIDE project, Lea is working on hominin occurrences in the Denizli Basin (Turkey) in order to assess the impact of climate and landscape dynamics on the western Anatolia region that is considered a biogeographic corridor during the Quaternary. She is working with ostracods, using them as paleoenvironmental and paleoclimatic proxies, rendering them a useful tool in the field of palaeoanthropodology. 

 

Sifan’s poster presentation focus was on modelling of extreme Caspian Sea area change on hydroclimate processes. The research tried to address the following two questions.

  • How significant are the impacts of CS area changes on regional (CS drainage areas) hydroclimate processes?
  • How do CS area changes can affect large scale climate?

As part of an ITN project his research focus is to develop a lake basin model for Pontocaspian basin. His main activities includes investigating climate change impacts on hydrological processes and identifying the drivers of sea level change during the Quaternary period (the last 2.5 million years) using hydroclimate modelling techniques.

PRIDE article published

We are pleased to let you know that the PRIDE article Quaternary time scales for the Pontocaspian domain: Interbasinal connectivity and faunal evolution, is now available online. This is the final open access version – containing full bibliographic details.

This article is written by 7 PRIDE early stage researchers, Wout Krijgsman, other PRIDE supervisors and PRIDE partners (see below).  https://doi.org/10.1016/j.earscirev.2018.10.013

W. Krijgsman, A. Tesakov, T. Yanina, S. Lazarev, G. Danukalova, C.G.C. Van Baak, J. Agustí, M.C. Alçiçek, E. Aliyeva, D. Bista, A. Bruch, Y. Büyükmeriç, M. Bukhsianidze, R. Flecker, P. Frolov, T.M. Hoyle, E.L. Jorissen, U. Kirscher, S.A. Koriche, S.B. Kroonenberg, D. Lordkipanidze, O. Oms, L. Rausch, J. Singarayer, M. Stoica, S. van de Velde, V.V. Titov, F.P. Wesselingh

PRIDE-RCMNS conference in Tbilisi

From 26 to 30 August 2018 PRIDE and RCMNS organised the PRIDE-RCMNS conference in Tbilisi, Georgia: Ecosystem isolation and connection: rise and demise of biota in the Pontocaspian-Caucasian regionAround 100 persons attended the conference. The conference was the final conference of PRIDE and it was an interim colloquium of the RCMNS, the Regional Committee on Mediterranean Neogene Stratigraphy.

We organised the conference together with and at the premises of the Georgian National Museum in Tbilisi. Many thanks to professor David Lordkipanidze, the director of the Museum, to Giorgi Bezarashvili, to Nino Kokolia, Mariam Inanishvili and Dr. Maia Bukshianidze and the rest of the Georgian team that organised everything so well. And many thanks to professor David Tarkhnishvili and to Dr. Levan Mumladze of department of Ecologoy of the Tbilisi State University.

Group picture of the conference

The registration desk and wonderful Georgian organisation team

Program booklets

Keycords

Program overviews

ESRs registering

ESRs checking their badge

Catering

Opening of the conference (left to right) Frank Wesselingh, Salomon Kroonenberg, Wout Krijgsman and David Lordkipanidze

Welcome and introduction by Frank Wesselingh (PRIDE Project director)

Talk of Sergei Lazarev: Reconstructing Pontocaspian interbasinal connections

The audience

Talk of Alberto Martinez Gandara: Rise and fall of the Pontocaspians

Talk of Aleksandre Gogaladze: Pontocaspian basin as a source and sink of invasive species: extent and mitigation strategies

Talk of Mikhail Karpinsky: Invasive species and their role in the Caspian ecosystem

Talk of Lea Rausch: Homo erectus paleoenvironments in the early Pleistocene Denizli Basin: an integrated paleontological, sedimentological and geochemical approach

Talk of Keith Richards: After the (Akchagylian) flood: what happened in the early to middle Pleistocene (Apsheronian-Bakunian) of the Caspian Sea?

Talk of Kateryna Kurakina (WWF Ukraine): The preservation of Sturgeon species in the Danube and Black Sea

Talk of Oriol Oms: The Neogene and Quaternary successions from Transcaucasian basins: advances from Georgia

The audience

The audience

Networking

Poster session

Poster session

Poster session

 

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