Environment, diversity, evolution and Cope's Rule: Drivers of size in planktonic foraminifera.

2020 ◽  
Author(s):  
Heather Birch ◽  
Daniela N. Schmidt ◽  
Chloe Todd ◽  
Marci M. Robinson ◽  
Andy Fraass
Keyword(s):  
High Resolution ◽  
Species Composition ◽  
Environmental Change ◽  
Planktonic Foraminifera ◽  
Maximum Diameter ◽  
Individual Species ◽  
Ecological Groups ◽  
General Increase ◽  
Foraminiferal Assemblage ◽  
Extant Species

<p>Within the marine fossil record, size is a fundamental trait providing information on both assemblages and individual species. Changes in size within an assemblage are largely driven by species composition typically related to environmental conditions. Changes in size of an individual species can be an indicator of health and whether optimal growth conditions (i.e. temperature, salinity and food availability) prevail. Over evolutionary timescales, individuals tend to increase in size (Cope’s rule) also altering the average size of the population.</p><p>The Pliocene provides an excellent opportunity to look at environmental drivers and ecological responses to a warmer world, at high resolution and with extant species. A short glaciation phase, during marine isotope stage (MIS) M2, interrupted the Pliocene global warming between ~ 3.31 – 3.26 Ma. This event provides the ideal framework to quantify how biota, already adapted to warming conditions, respond to a short, but substantial cooling event. </p><p>We analysed the size and species composition of samples collected as part of the Pliocene Research, Interpretation and Synoptic Mapping (PRISM) Project from a variety of locations around the globe. The samples cover the Atlantic, Indian and Pacific oceans at a range of latitudes (e.g. DSDP Site 521, 586, 607 and ODP Site 716, 754, 887). We measured the maximum diameter of planktonic foraminifera tests with a fully automated light microscope, enabling high resolution sampling at a multitude of sites, before, during and after the MIS M2 glaciation event. On average 2000 specimens were measured per sample, resulting in over a million analyses in total. Changes in planktonic foraminiferal assemblage composition were characterised by quantifying relative species abundances and augmented by determining the largest species.</p><p>Planktonic foraminiferal assemblage size shows a general increase during the Pliocene likely related to warming temperatures. What is unclear is if this change is driven by changes in diversity due to extinction and origination, responses to environmental change or a general increase in size of species found through the record. Here we discuss reactions of species and (or) ecological groups to environmental change and determine the individual drivers of size change across the world’s oceans.</p>

scholarly journals Quantifying the effect of seasonal and vertical habitat tracking on planktonic foraminifera proxies

2017 ◽  
Vol 13 (6) ◽  
pp. 573-586 ◽  
Author(s):  
Lukas Jonkers ◽  
Michal Kučera
Keyword(s):  
Environmental Change ◽  
Data Model ◽  
Model Comparison ◽  
Planktonic Foraminifera ◽  
Temporal Trends ◽  
Global Scale ◽  
Individual Species ◽  
Near Surface ◽  
Proxy Records ◽  
Habitat Tracking

Abstract. The composition of planktonic foraminiferal (PF) calcite is routinely used to reconstruct climate variability. However, PF ecology leaves a large imprint on the proxy signal: seasonal and vertical habitats of PF species vary spatially, causing variable offsets from annual mean surface conditions recorded by sedimentary assemblages. PF seasonality changes with temperature in a way that minimises the environmental change that individual species experience and it is not unlikely that changes in depth habitat also result from such habitat tracking. While this behaviour could lead to an underestimation of spatial or temporal trends as well as of variability in proxy records, most palaeoceanographic studies are (implicitly) based on the assumption of a constant habitat. Up to now, the effect of habitat tracking on foraminifera proxy records has not yet been formally quantified on a global scale. Here we attempt to characterise this effect on the amplitude of environmental change recorded in sedimentary PF using core top δ18O data from six species. We find that the offset from mean annual near-surface δ18O values varies with temperature, with PF δ18O indicating warmer than mean conditions in colder waters (on average by −0.1 ‰ (equivalent to 0.4 °C) per °C), thus providing a first-order quantification of the degree of underestimation due to habitat tracking. We use an empirical model to estimate the contribution of seasonality to the observed difference between PF and annual mean δ18O and use the residual Δδ18O to assess trends in calcification depth. Our analysis indicates that given an observation-based model parametrisation calcification depth increases with temperature in all species and sensitivity analysis suggests that a temperature-related seasonal habitat adjustment is essential to explain the observed isotope signal. Habitat tracking can thus lead to a significant reduction in the amplitude of recorded environmental change. However, we show that this behaviour is predictable. This allows accounting for habitat tracking, enabling more meaningful reconstructions and improved data–model comparison.

scholarly journals Response of North American mammal communities to late Quaternary environmental fluctuations

1992 ◽  
Vol 6 ◽  
pp. 112-112 ◽  
Author(s):  
Russell W. Graham
Keyword(s):  
Species Composition ◽  
Small Mammal ◽  
Late Quaternary ◽  
Individual Species ◽  
Glacial Ice ◽  
The Holocene ◽  
Environmental Models ◽  
Extant Species ◽  
Environmental Fluctuations ◽  
Mammal Communities

The late Quaternary was a time of rapid environmental fluctuations. The last glacial maximum was reached about 20 ka with continental glaciers covering most of Canada as well as the northeastern and upper midwestern United States (U.S.). Glacial ice physically displaced entire terrestrial biomes and the cooler climates altered distributions of species outside of the glacial limits. About 14 ka, the climate began to warm rapidly and glacial ice retreated northward, opening new landscapes for colonization by terrestrial biotas. Maximum warmth was reached between 9–5 ka with a time transgressive progression from west to east.Radiocarbon chronologies allow for fine scale (100's to 1000's of years) resolution of mammal responses to these changes. Mammal communities did not respond as intact units but individual species shifted diachronically along environmental gradients. As a result, many late Pleistocene mammal communities contain associations of extant species that do not occur together today and appear to be ecologically incompatible. Pleistocene mammal communities also had a greater diversity of species than either Holocene or modern ones. This greater diversity was, in part, due to the existence of a diverse megafauna that became extinct at the end of the Pleistocene (10 ka). However, Pleistocene small mammal guilds with extant species, especially insectivores and microtine rodents, were also more diverse. Rapid changes in small mammal species distributions, diversity patterns, and clinal shifts around 10 ka strengthens environmental models for the end-Pleistocene extinction.Modern mammal communities began to appear at the end of the Pleistocene and into the Holocene. In the eastern U.S., the species composition of these communities has been stable for the last 10 ka, although vegetational communities have shown change throughout the Holocene. In other parts of the U.S., middle Holocene warming caused some species to shift their geographic ranges. However, species composition of communities was not significantly altered. Understanding these changes not only provides a better perspective for viewing mammal communities of the past but it may also give insight into those of the future as climate will continue to vacillate, whether induced naturally or anthropogenically.

Decapod Crustaceans of the Kara Sea: species composition and peculiarities of distribution

2021 ◽  
Vol 325 (3) ◽  
pp. 364-372
Author(s):  
O.L. Zimina
Keyword(s):  
Species Composition ◽  
Environmental Conditions ◽  
Kara Sea ◽  
Individual Species ◽  
Snow Crab ◽  
Western Slope ◽  
Depth Range ◽  
Ecological Groups ◽  
Decapod Crustaceans ◽  
Wide Range

This paper presents data on species composition and peculiarities of distribution of Decapoda in the southern part of Kara Sea obtained during trawl surveys in 2012 and 2016. In total, 11 species of decapod crustaceans were collected. In the last decade the fauna has been enriched by the invasion of the snow crab Chionoecetes opilio. Brief information on the environmental conditions of occurrence and maps of distribution in the studied area are presented for each species. The highest values of species richness (up to 6 species per catch), biomass and abundance of decapods were detected on the western slope of Priyamal shallow at 50–150 m depth range. According to the patterns of distribution and environmental conditions, three groups of species were distinguished: associated with cold and salty waters of Novaya Zemlya Trough; inhabiting lower salinity waters with a wide temperature range of the Priyamal and Ob-Yenisei shallows; and a group that is widespread within the area in wide range of conditions. In comparison with the neighboring Barents Sea, the decapod fauna of the Kara Sea is qualitatively and quantitatively depleted. The obtained data on the distribution of individual species and ecological groups can be used for the background assessment of the state of the decapod fauna, including the period of population formation of the alien species.

scholarly journals Transformation of the community of nesting birds in the process of reorganization of the forest ecosystem into a park

2019 ◽  
Vol 30 (1) ◽  
pp. 3-13 ◽  
Author(s):  
V. A. Gaychenko ◽  
T. V. Shupova
Keyword(s):  
Species Composition ◽  
Relative Abundance ◽  
Forest Ecosystem ◽  
Bird Species ◽  
Bird Communities ◽  
Individual Species ◽  
Natural State ◽  
Forest Steppe ◽  
Ecological Groups ◽  
Anthropogenic Landscapes

Changes in nesting conditions cause a change in the number of individual species, ecological groups, and, consequently, the structure of the bird community. The purpose of the study is to analyze the possibilities and directions – the transformations of the communitys of nesting birds in the process of reorganization of the forest ecosystem into a park. The material was collected in the territory of one of the forest parks in the Kiev city. Forest is an mixed based on Quercus robur L., Carpinus betulus L., Acer platanoides L., Tilia cordata L., Fraxinus excelsior L. There are individual trees Pinus Syvestris L. The territory of the forest park have different degrees transformed, and includes anthropogenic landscapes and forests plots that have been preserved almost in their natural state. Studies were conducted in the nesting period (April-June) 2012–2017. For analysis average data were used. The number and distribution of the birds were determined by the method of counting on the transects, in the 3 model plots. There are 71 species of birds of 11 orders. Of these, 63 species are nesting. The number of nested species of communities in model plots does not depend on the gradient of anthropogenic transformation, but a average density of nesting birds decrease: 2.91±0.66→2.54±0.67→2.10±0.48 pairs / km of the transect. Nesting birds are distributed between 9 faunogenetic complexes. Of these, in each model plot is represented by 8. Dominated by birds of the European nemoral complex. On the gradient of habitat transformation, a change in the fauna-genetic structure of bird communities in the direction of increasing the proportion of birds of the European nemoral and European forest-steppe complexes, birds of desert-mountain and tropical groups. Boreal and ancient species are superseded. Strengthening the transformation in forest plots, the distribution of birds in community on the ecological groups does change not much. But when the forest ecosystem is replaced by a park ecosystem, the proportion of sclerophiles increases 3–4 times. In all communities is dominated by woody nesters bird. On the gradient of transformation, the number of species of the tree canopies nesters birds (from 21 to 18), ground nesters birds (from 6 to 0), species that use many types of nesting stations (from 4 to 1) are decreases; the number of bird species that nesting in the buildings increases from 0 to 6, and the number of alien species from 0 to 4 (Streptopelia decaocto, Dendrocopos syriacus, Phoenicurus ochruros, Serinus serinus). In the park ecosystems, a decrease in the species composition of woodpeckers, does not entail a significant decrease in the species composition and abundance of secondary hollows nesters birds. Birds of the synanthropic subpopulations are nesting in cavities in park buildings. Most of the indices show an equivalent ά-diversity of all bird communities. The β-diversity of breeding birds during the transformation of the forest ecosystem into a park is reduced by half. Ranked distribution curves of the abundance of species are indicate abrupt changes in the balance of dominance-diversity in communities when a transformation are in the forest ecosystem. The dominant species pressure high are give in community, its abundance is 2.2–2.7 times higher than the abundance of the second species by the abundance. In a slightly transformed forest, this indicator is 1.1 times. Ranked curves of relative abundance of species are a more sensitive index of community transformation than data of indices by the dominance and of species distribution. The introduction into the forest ecosystem of even a small number of anthropogenic structures leads to a significant increase in the relative abundance of synanthropic birds. In our study, in to 2 times. On the gradient of the transformation the absolute number of nesting species of the synanthropic birds increases gradually: 30–33–36; the obligate synanthropic species more stronger: 0–2–7; the index of community synanthropization increases 1.5 times: 0.63–0.72–0.92.

scholarly journals Quantifying the effect of seasonal and vertical habitat tracking on planktonic foraminifera proxies

2016 ◽  
Author(s):  
Lukas Jonkers ◽  
Michal Kučera
Keyword(s):  
Environmental Change ◽  
Model Comparison ◽  
Cold Water ◽  
Planktonic Foraminifera ◽  
Temporal Trends ◽  
Individual Species ◽  
Tropical Species ◽  
Near Surface ◽  
Proxy Records ◽  
Habitat Tracking

Abstract. The composition of planktonic foraminiferal (PF) calcite is routinely used to reconstruct climate change and variability. However, PF ecology leaves a large imprint on the proxy signal. The seasonal and vertical habitat of planktonic foraminifera (PF) species varies spatially, causing variable offsets from annual mean surface conditions recorded by sedimentary assemblages. PF seasonality changes with temperature in a way that minimises the environmental change that individual species experience. While such habitat tracking could lead to an underestimation of spatial or temporal trends and variability in proxy records, most paleoceanographic studies are based on the assumption of a constant habitat. Although the controls on depth habitat variability are less well constrained, it is not unlikely that habitat tracking also affects PF depth habitat. Despite the implications, the effect of this behaviour on foraminifera proxy records has not yet been formally quantified on a global scale. Here we attempt to characterise the effect of habitat tracking on the amplitude of environmental change recorded in sedimentary PF using core top δ18O data from six species, which we compare to predicted δ18O. We find that the offset from mean annual near-surface δ18O values varies with temperature, with PF δ18O indicating warmer than mean conditions in colder waters (on average by −0.1 ‰ (or 0.4°C) per °C), thus providing a first-order quantification of the degree of underestimation due to habitat tracking. We then use an empirical model to estimate the contribution of seasonality to the observed difference between PF and annual mean δ18O and use the residual Δδ18O to assess trends in calcification depth. Our analysis indicates that in all species calcification depth increases with temperature. Consistent with hydrographic conditions, vertical habitat adjustment is dominant in tropical species, whereas cold-water species mainly changes their seasonality when tracking their "optimum" habitat. Assumptions of constant PF depth or seasonal habitat made when interpreting proxy records are thus invalid. The approach outlined here can be used to account for these effects, enabling more accurate reconstructions and improved data-model comparison.

scholarly journals The benthic foraminiferal response to the mid-Maastrichtian event in the Maastrichtian-type area

2021 ◽  
Author(s):  
Iris Vancoppenolle ◽  
Johan Vellekoop ◽  
Monika Doubrawa ◽  
Pim Kaskes ◽  
Matthias Sinnesael ◽  
...  
Keyword(s):  
High Resolution ◽  
Environmental Changes ◽  
Planktonic Foraminifera ◽  
Oceanic Circulation ◽  
Foraminiferal Assemblage ◽  
Carbonate Carbon ◽  
Sea Bottom ◽  
Type Area ◽  
Stratigraphic Position ◽  
Species Specific

<p>The mid-Maastrichtian event (MME), ~69 Ma, represents a global negative δ<sup>13</sup>C excursion which is linked to the extinction of inoceramid bivalves and latitudinal migration of planktonic foraminifera. While the actual extinction of inoceramids was diachronous across the globe, the decline of this important fossil group is generally linked to environmental changes across the mid-Maastrichtian interval. The MME is potentially related to changes in oceanic circulation. While the MME, and associated decline of inoceramids, has been recorded from a variety of deep-sea sites, little is known about the MME signature in shallow epicontinental environments.</p><p>Recently, the MME has been recorded for the first time from the type-Maastrichtian, in the Maastricht-Liège region (The Netherlands and Belgium), in newly generated bulk carbonate carbon isotope records from the Hallembaye quarry (NE Belgium) and former ENCI quarry (SE Netherlands). These quarries are approximately 8 km apart. The type-Maastrichtian succession was deposited in a shallow subtropical sea during the Late Cretaceous. As the stratigraphic position of the MME is now constrained in the type-Maastrichtian record, this succession presents an interesting opportunity for studying the signature of this event in a relatively shallow epicontinental basin. Therefore, we are generating high-resolution benthic foraminiferal assemblage data and species-specific carbon and oxygen stable isotope records across the MME interval at these two quarries, in order to unravel biotic and environmental expressions of the MME in the Maastrichtian type area. This is done using the high-resolution sample set acquired in the context of the Maastrichtian Geoheritage Project. Our preliminary data show a distinctive acme of the benthic foraminifer <em>Cuneus trigona</em> in the interval that roughly that corresponds to the MME, potentially caused by a change in quality of the organic matter that reached the sea bottom, highlighting local environmental and oceanographic perturbations across this event.</p>

Kyiv park "Nivki" and "Teremki" forests and ecological analysis of their habitats

2014 ◽  
Vol 25 (3-4) ◽  
pp. 53-68
Author(s):  
I. V. Goncharenko ◽  
H. M. Holyk
Keyword(s):  
Standard Deviation ◽  
Species Composition ◽  
Human Impact ◽  
Soil Nitrogen ◽  
Beta Diversity ◽  
Plant Cover ◽  
Alpha Diversity ◽  
Light Regime ◽  
Individual Species ◽  
Anthropogenic Pressure

Cenotic diversity and leading ecological factors of its floristic differentiation were studied on an example of two areas – Kyiv parks "Nivki" and "Teremki". It is shown that in megalopolis the Galeobdoloni-Carpinetum impatientosum parviflorae subassociation is formed under anthropogenic pressure on the typical ecotope of near-Dnieper hornbeam oak forests on fresh gray-forest soils. The degree of anthropogenic transformation of cenofloras can be estimated by the number of species of Robinietea and Galio-Urticetea classes, as well as neophytes and cultivars. Phytoindication for hemeroby index may be also used in calculation. We propose the modified index of biotic dispersion (normalized by alpha-diversity) for the estimation of ecophytocenotic range (beta-diversity) of releves series. We found that alpha-diversity initially increases (due to the invasion of antropophytes) at low level of antropogenic pressure, then it decreases (due to the loss of aboriginal species) secondarily with increasing of human impact. Also we found that beta-diversity (differential diversity) decreases, increasing homogeneity of plant cover, under the influence of anthropogenic factor. Vegetation classification was completed by a new original method of cluster analysis, designated as DRSA («distance-ranked sorting assembling»). The classification quality is suggested to be validated on the "seriation" diagram, which is а distance matrix between objects with gradient filling. Dark diagonal blocks confirm clusters’ density (intracluster compactness), uncolored off-diagonal blocks are evidence in favor of clusters’ isolation (intercluster distinctness). In addition, distinction of clusters (syntaxa) in ordination area suggests their independence. For phytoindication we propose to include only species with more than 10% constancy. Furthermore, for the description of syntaxonomic amplitude we suggest to use 25%-75% interquartile scope instead of mean and standard deviation. It is shown that comparative analysis of syntaxa for each ecofactor is convenient to carry out by using violin (bulb) plots. A new approach to the phytoindication of syntaxa, designated as R-phytoindication, was proposed for our study. In this case, the ecofactor values, calculated for individual releves, are not taken into account, however, the composition of cenoflora with species constancies is used that helps us to minimize for phytoindication the influence of non-typical species. We suggested a syntaxon’s amplitude to be described by more robust statistics: for the optimum of amplitude (central tendency) – by a median (instead of arithmetic mean), and for the range of tolerance – by an interquartile scope (instead of standard deviation). We assesses amplitudes of syntaxa by phytoindication method for moisture (Hd), acidity (Rc), soil nitrogen content (Nt), wetting variability (vHd), light regime (Lc), salt regime (Sl). We revealed no significant differences on these ecofactors among ecotopes of our syntaxa, that proved the variant syntaxonomic rank for all syntaxa. We found that the core of species composition of our phytocenoses consists of plants with moderate requirements for moisture, soil nitrogen, light and salt regime. We prove that the leading factor of syntaxonomic differentiation is hidden anthropogenic, which is not subject to direct measurement. But we detect that hidden factor of "human pressure" was correlated with phytoindication parameters (variables) that can be measured "directly" by species composition of plant communities. The most correlated factors were ecofactors of soil nitrogen, wetting variability, light regime and hemeroby. The last one is the most indicative empirically for the assessment of "human impact". We establish that there is a concept of «hemeroby of phytocenosis» (tolerance to human impact), which can be calculated approximately as the mean or the median of hemeroby scores of individual species which are present in it.

Carabidae of Barnaul city parks: ecological characteristics and species composition

2018 ◽  
Vol 8 (2) ◽  
pp. 348-353
Author(s):  
E. A. Kuchina ◽  
N. D. Ovcharenko ◽  
L. D. Vasileva
Keyword(s):  
Species Composition ◽  
Diversity Index ◽  
Similarity Index ◽  
Life Forms ◽  
Ground Beetles ◽  
Forest Steppe ◽  
Ecological Groups ◽  
Dominant Group ◽  
Species Diversity Index ◽  
Steppe Species

<p>Anthropogenic impact on the population of ground beetles leads to a change in their numbers, structure of dominance, density, species composition, spectrum of life forms. This makes the beetles Carabidae a convenient and informative bioindicator of the ecological state of biocenoses. The material for this work was the Carabidae collections conducted in June-August 2016-2017 in the park zone of different regions of Barnaul, differing in location, area, hydrological regime, vegetation cover, purpose and anthropogenic load. When processing the material, the quantitative, species and generic composition of the carabidae was determined, calculations were made for such indicators as the Berger-Parker dominance index, the Shannon species diversity index (Hs), and the Jacquard species similarity index. The fauna (Coleoptera, Carabidae) of the park zone of Barnaul is represented by 55 species belonging to 20 genera. The dominant group is represented by species belonging to steppe, forest and polyzonal groups. Forest-steppe species of ground beetles as dominants have not been identified in any of the investigated territories. The greatest variety of ecological groups was noted on the territory of the Yubileyny рark, which is explained by the presence of zones with various microclimatic conditions, the presence of a birch grove that flows through the park with the Pivovarka River, and a wide log in the park. Registered species belong to eight groups of life forms belonging to two classes - zoophagous and myxophytophagous. On the numerical and species abundance, zoophages predominate. The spectrum of life forms corresponds to the zonal spectrum characteristic of the forest-steppe zone.</p><p> </p>

The crucial boundaries in the development of the late cretaceous biota of plankton foraminifers in the southern part of the Indian ocean

2019 ◽  
Vol 59 (6) ◽  
pp. 1074-1085
Author(s):  
E. A. Sokolova
Keyword(s):  
Indian Ocean ◽  
Species Composition ◽  
Late Cretaceous ◽  
Upper Cretaceous ◽  
Planktonic Foraminifera ◽  
The Indian Ocean ◽  
Systematic Composition ◽  
Climatic Series

The article analyzes own data on the species composition of shells of planktonic foraminifera from the Upper Cretaceous sediments of the Indian Oceans, as well as from the sections of the offshore seas of Australia. The species of planktonic foraminifera are grouped and arranged in a climatic series. An analysis of the change in the systematic composition of foraminifers made it possible to distinguish periods of extreme and intermediate climatic states in the Late Cretaceous.

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