Ecological Response of Plankton to Environmental Change – Thresholds for Extinction

Ecological Response of Plankton to Environmental Change: Thresholds for Extinction

Annual Review of Earth and Planetary Sciences ◽

10.1146/annurev-earth-081619-052818 ◽

2020 ◽

Vol 48 (1) ◽

pp. 403-429 ◽

Cited By ~ 7

Author(s):

Christopher M. Lowery ◽

Paul R. Bown ◽

Andrew J. Fraass ◽

Pincelli M. Hull

Keyword(s):

Environmental Change ◽

Water Column ◽

Environmental Changes ◽

Marine Biodiversity ◽

Marine Biota ◽

Marine Plankton ◽

Planktic Foraminifera ◽

Water Column Stratification ◽

Extinction Events ◽

Plankton Diversity

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 majorclimatic shifts affecting water column stratification, temperature, and, perhaps, chemistry. Changes that strongly affect the benthos, such as acidification and anoxia, have little effect on the plankton or are associated with radiation. ▪ Fossilizing marine plankton provide some of the most highly temporally and taxonomically resolved records of biodiversity since the Mesozoic. ▪ The record of extinction and origination in the plankton differs from the overall marine biodiversity record in revealing ways. ▪ Changes to water column stratification and global circulation are the main drivers of plankton diversity. ▪ Anoxia, acidification, and eutrophication (which strongly influence total marine fossil diversity) are less important in the plankton.

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Coral reef development drives molluscan diversity increase at local and regional scales in the late Neogene and Quaternary of the southwestern Caribbean

Paleobiology ◽

10.1666/06022.1 ◽

2007 ◽

Vol 33 (1) ◽

pp. 24-52 ◽

Cited By ~ 26

Author(s):

Kenneth G. Johnson ◽

Jonathan A. Todd ◽

Jeremy B. C. Jackson

Keyword(s):

Environmental Change ◽

Shallow Water ◽

Large Scale ◽

Environmental Changes ◽

Marine Biota ◽

Environmental Distribution ◽

Data Set ◽

Ecological Response ◽

Local Diversity ◽

Late Neogene

The late Neogene was a time of major environmental change in Tropical America. Global cooling and associated oceanographic reorganization and the onset and intensification of glaciation in the Northern Hemisphere during the past ten million years coincided with the uplift of the Central American isthmus and resulting changes in regional oceanographic conditions. Previous analyses of patterns of taxonomic turnover and the shifting abundances of major ecological guilds indicated that the regional shallow-water marine biota responded to these environmental changes through extinction and via a restructuring of local benthic food webs, but it is not clear whether this ecological response had an effect on the diversity of molluscan assemblages in the region. Changes in regional and local diversity are often used as proxies for similar ecological response to environmental change in large-scale paleontological studies, but a clear relationship between diversity and ecological function has rarely been demonstrated in marine systems dominated by mollusks. To explore this relationship, we have compiled a data set of the stratigraphic and environmental distribution of genera of mollusks in large new collections of fossil specimens from the late Neogene and Recent of the southwestern Caribbean. Analysis of a selection of ecological diversity measures indicates that within shelf depths, assemblages from deeper water (51–200 m) were more diverse than shallow-water (<50 m) assemblages in the Pliocene. Lower diversity for shallow-water assemblages is caused by increased dominance of a few superabundant taxa in each assemblage. This implies that studies of diversity of shelf benthos need to control for relatively fine scaled environmental conditions if they are to avoid interpreting artifacts of uneven sampling as true change of diversity. For shallow-water assemblages only, there was significant increase in local and regional diversity of bivalve assemblages after the late Pliocene. No parallel increase in gastropods could be detected, but this likely is because sample size was inadequate for documenting the diversity of gastropod assemblages following a steep post-Pliocene decline of average gastropod abundance. Both the increasing bivalve diversity and the decrease in average abundance of gastropod taxa correspond to an interval of increasing carbonate deposition and reef building in the region, and are likely a result of increased fine-scale habitat heterogeneity controlled by the local distribution of carbonate buildups. Each of these results demonstrates that documenting the ecological response of tropical marine ecosystems to regional environmental change requires a large volume of fine-scaled samples with detailed paleoenvironmental control. Such data sets are rarely available from the fossil record.

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Identifying the most surprising victims of mass extinction events: an example using Late Ordovician brachiopods

Biology Letters ◽

10.1098/rsbl.2017.0400 ◽

2017 ◽

Vol 13 (9) ◽

pp. 20170400 ◽

Cited By ~ 7

Author(s):

Seth Finnegan ◽

Christian M. Ø. Rasmussen ◽

David A. T. Harper

Keyword(s):

Deep Water ◽

Mass Extinction ◽

Late Ordovician ◽

Extinction Rate ◽

Simple Method ◽

Training Models ◽

Extinction Event ◽

Extinction Events ◽

Mass Extinction Events

Mass extinction events are recognized by increases in extinction rate and magnitude and, often, by changes in the selectivity of extinction. When considering the selective fingerprint of a particular event, not all taxon extinctions are equally informative: some would be expected even under a ‘background’ selectivity regime, whereas others would not and thus require special explanation. When evaluating possible drivers for the extinction event, the latter group is of particular interest. Here, we introduce a simple method for identifying these most surprising victims of extinction events by training models on background extinction intervals and using these models to make per-taxon assessments of ‘expected’ risk during the extinction interval. As an example, we examine brachiopod genus extinctions during the Late Ordovician Mass Extinction and show that extinction of genera in the deep-water ‘ Foliomena fauna’ was particularly unexpected given preceding Late Ordovician extinction patterns.

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Testing for a mass extinction without selecting taxa

Paleobiology ◽

10.1666/0094-8373(2000)026<0647:tfamew>2.0.co;2 ◽

2000 ◽

Vol 26 (4) ◽

pp. 647-650 ◽

Cited By ~ 16

Author(s):

Andrew R. Solow ◽

Woollcott K. Smith

Keyword(s):

Statistical Inference ◽

Mass Extinction ◽

Extinction Event ◽

Mass Extinction Event ◽

Extinction Events ◽

Mass Extinction Events ◽

Stratigraphic Height ◽

Selection Of

Statistical inference about mass extinction events is commonly based on the pattern of fossil finds among a group of taxa. An important issue for existing methods is the selection of taxa for inclusion in the analysis. A common approach is to select taxa on the basis of the stratigraphic height of their uppermost finds. This approach creates a bias in favor of detecting a mass extinction event. This paper describes and illustrates an approach that avoids this problem.

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Dead clades walking are a pervasive macroevolutionary pattern

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2019208118 ◽

2021 ◽

Vol 118 (15) ◽

pp. e2019208118

Author(s):

B. Davis Barnes ◽

Judith A. Sclafani ◽

Andrew Zaffos

Keyword(s):

Mass Extinction ◽

Bayesian Method ◽

Marine Invertebrate ◽

Mass Extinctions ◽

Extinction Event ◽

Genus Richness ◽

Mass Extinction Event ◽

Extinction Events ◽

Mass Extinction Events

D. Jablonski [Proc. Natl. Acad. Sci. U.S.A. 99, 8139–8144 (2002)] coined the term “dead clades walking” (DCWs) to describe marine fossil orders that experience significant drops in genus richness during mass extinction events and never rediversify to previous levels. This phenomenon is generally interpreted as further evidence that the macroevolutionary consequences of mass extinctions can continue well past the formal boundary. It is unclear, however, exactly how long DCWs are expected to persist after extinction events and to what degree they impact broader trends in Phanerozoic biodiversity. Here we analyze the fossil occurrences of 134 skeletonized marine invertebrate orders in the Paleobiology Database (paleobiodb.org) using a Bayesian method to identify significant change points in genus richness. Our analysis identifies 70 orders that experience major diversity losses without recovery. Most of these taxa, however, do not fit the popular conception of DCWs as clades that narrowly survive a mass extinction event and linger for only a few stages before succumbing to extinction. The median postdrop duration of these DCW orders is long (>30 Myr), suggesting that previous studies may have underestimated the long-term taxonomic impact of mass extinction events. More importantly, many drops in diversity without recovery are not associated with mass extinction events and occur during background extinction stages. The prevalence of DCW orders throughout both mass and background extinction intervals and across phyla (>50% of all marine invertebrate orders) suggests that the DCW pattern is a major component of macroevolutionary turnover.

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Modern Coral Reefs Under Global Change: New Opportunities to Understand Carbonate Depositional Hiatuses

The Paleontological Society Papers ◽

10.1017/s1089332600002485 ◽

2011 ◽

Vol 17 ◽

pp. 121-130 ◽

Cited By ~ 2

Author(s):

Pamela Hallock

Keyword(s):

Global Change ◽

Coral Reefs ◽

Environmental Change ◽

Mass Extinction ◽

Paleoenvironmental Changes ◽

Carbonate Sedimentation ◽

Depositional Systems ◽

Geologic Record ◽

Extinction Events ◽

Mass Extinction Events

As shallow-water reefs decline worldwide, opportunities abound for researchers to expand understanding of carbonate depositional systems. Recognizing the myriad of paradoxes associated with reefs and carbonate research hopefully can stimulate new questions that will assist researchers in understanding paleoenvironmental changes and mass extinction events. Two often counter-intuitive concepts are discussed, first that coral reefs thrive in clear, nutrient-poor waters, except when they don't; and second, that aragonite is energetically efficient for reef-builders to precipitate in tropical waters, except when it isn't. Coordinated studies of carbonate geochemistry with photozoan physiology and calcification will contribute to understanding carbonate sedimentation under environmental change, both in the future and in the geologic record.

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

Royal Society Open Science ◽

10.1098/rsos.170899 ◽

2017 ◽

Vol 4 (11) ◽

pp. 170899 ◽

Cited By ~ 2

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.

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Securing sustainability: the case for critical environmental security in the Arctic

Polar Record ◽

10.1017/s0032247416000218 ◽

2016 ◽

Vol 52 (6) ◽

pp. 660-671 ◽

Cited By ~ 7

Author(s):

W. Greaves

Keyword(s):

Environmental Change ◽

Environmental Changes ◽

Arctic Region ◽

Environmental Security ◽

The Arctic ◽

Security Issues ◽

Arctic Security ◽

Robert Cox ◽

Critical Account ◽

The Relationship

ABSTRACTThe politics, economies, and ecology of the Arctic region are experiencing fundamental transformation driven largely by human-caused environmental change. Drawing on the work of Robert Cox, this article presents a critical account of environmental security that allows security issues in the Arctic to be reconceptualised. It outlines the environmental changes transforming the Arctic, and theorises the Arctic as a regional environmental security complex in which conditions of security for state and non-state referent objects are predicated on a particular ecological context. It then surveys state- and human security issues in the Arctic, and argues that environmental change has destabilised the ecological base on which the contemporary Arctic as a cooperative region supportive of human activity has been built. The article concludes by outlining alternative ways of conceiving of Arctic security that are more compatible with maintaining the region's ecological base, and suggests that dominant approaches to Arctic security are pathological because they remain premised on the control, extraction and consumption of hydrocarbon resources. It argues that, in the context of the geological Anthropocene, security cannot be sustainable if it fails to address the relationship between human wellbeing and human-caused environmental change, or informs practices that further contribute to environmental change.

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Mesozoic marine tetrapod diversity: mass extinctions and temporal heterogeneity in geological megabiases affecting vertebrates

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2009.1845 ◽

2009 ◽

Vol 277 (1683) ◽

pp. 829-834 ◽

Cited By ~ 139

Author(s):

Roger B. J. Benson ◽

Richard J. Butler ◽

Johan Lindgren ◽

Adam S. Smith

Keyword(s):

Marine Invertebrates ◽

Mass Extinctions ◽

True Diversity ◽

Extinction Event ◽

Sampling Regime ◽

Extinction Events ◽

Fossil Preservation ◽

Taxic Diversity ◽

Mass Extinction Events

The fossil record is our only direct means for evaluating shifts in biodiversity through Earth's history. However, analyses of fossil marine invertebrates have demonstrated that geological megabiases profoundly influence fossil preservation and discovery, obscuring true diversity signals. Comparable studies of vertebrate palaeodiversity patterns remain in their infancy. A new species-level dataset of Mesozoic marine tetrapod occurrences was compared with a proxy for temporal variation in the volume and facies diversity of fossiliferous rock (number of marine fossiliferous formations: FMF). A strong correlation between taxic diversity and FMF is present during the Cretaceous. Weak or no correlation of Jurassic data suggests a qualitatively different sampling regime resulting from five apparent peaks in Triassic–Jurassic diversity. These correspond to a small number of European formations that have been the subject of intensive collecting, and represent ‘Lagerstätten effects’. Consideration of sampling biases allows re-evaluation of proposed mass extinction events. Marine tetrapod diversity declined during the Carnian or Norian. However, the proposed end-Triassic extinction event cannot be recognized with confidence. Some evidence supports an extinction event near the Jurassic/Cretaceous boundary, but the proposed end-Cenomanian extinction is probably an artefact of poor sampling. Marine tetrapod diversity underwent a long-term decline prior to the Cretaceous–Palaeogene extinction.

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Environmental Change and Migration in Morocco: What Has Been Done So Far?

IMISCOE Research Series - Migration and Environmental Change in Morocco ◽

10.1007/978-3-030-61390-7_3 ◽

2021 ◽

pp. 35-59

Author(s):

Lore Van Praag ◽

Loubna Ou-Salah ◽

Elodie Hut ◽

Caroline Zickgraf

Keyword(s):

Environmental Change ◽

Environmental Changes ◽

Interesting Case ◽

Environmental Migration ◽

Migration History ◽

History Of ◽

And Migration ◽

High Degree ◽

Unexpected Outcomes ◽

The Relationship

AbstractBefore we delve further into the relationship between migration and environmental change, it is important to gain more insight into the migration history of Moroccans going abroad and the specific environmental changes faced by people in Morocco. Therefore, in the first part of this chapter, we outline the history of Moroccan migration to Europe in general and to Belgium in particular. Morocco provides an interesting case of study with regard to environmental migration, as in the second half of the twentieth century, Morocco evolved into one of the world’s leading emigration countries. Moroccan migration is one of the unexpected outcomes in which colonial migration, labour migration, family reunification, and, most recently, undocumented migration combine. Hence, there is a high degree of internal differentiation and dynamics within the migrant population of Morocco (De Haas 2007).

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