scholarly journals Effects of several in-feed antibiotic combinations on the abundance and diversity of fecal microbes in weaned pigs

2017 ◽  
Vol 63 (5) ◽  
pp. 402-410 ◽  
Author(s):  
Huizhi Li ◽  
Tingting Liang ◽  
Qingpo Chu ◽  
Feilong Xu ◽  
Yuan Li ◽  
...  
Keyword(s):  
Experimental Data ◽  
High Throughput Sequencing ◽  
Antibiotic Administration ◽  
Weaned Pigs ◽  
Intestinal Microbes ◽  
Β Diversity ◽  
Α Diversity ◽  
Relative Abundances ◽  
Abundance And Diversity ◽  
Zinc Bacitracin

To characterize the effects of several subtherapeutic antibiotic combinations on the abundance and diversity of fecal microbes, 400 weaned pigs were selected and randomly assigned to 8 groups, where they were continuously fed different antibiotic combinations for 28 days. Then, a total of 48 pigs were randomly selected to collect feces samples for DNA extraction and 16S rRNA high-throughput sequencing. Compared with that of pigs without antibiotic administration, the diversities of fecal microbes were decreased in the pigs fed chlortetracycline (CTC), olaquindox (OLA), and either enramycin (ER) or virginiamycin (VIR), and the relative abundances of members of the phylum Bacteroidetes and the genus Prevotella were increased. Compared with that of pigs without antibiotic administration, the relative abundances of members of the phylum Proteobacteria and the genus Succinivibrio were decreased in the pigs fed CTC, a mixture of zinc bacitracin (ZB) + colistin sulfate (COL), a mixture of CTC+ZB+COL, a mixture of CTC+OLA, or a mixture of CTC+OLA+ER. α-Diversity and β-diversity were decreased (P < 0.05) in the pigs fed ZB+COL or a mixture of CTC+OLA+ER or CTC+OLA+VIR. This study provides experimental data to deepen our understanding on the effects of antibiotic combinations on intestinal microbes.

Patterns in diversity and composition of the microbenthos of subarctic intertidal beaches with different morphodynamics

2020 ◽  
Vol 648 ◽  
pp. 19-38
Author(s):  
AI Azovsky ◽  
YA Mazei ◽  
MA Saburova ◽  
PV Sapozhnikov
Keyword(s):  
Species Abundance ◽  
Abundance Ratio ◽  
Wave Action ◽  
Coarse Grained ◽  
Sediment Properties ◽  
Β Diversity ◽  
Α Diversity ◽  
Wide Range ◽  
Similar Mode ◽  
Abundance And Diversity

Diversity and composition of benthic diatom algae and ciliates were studied at several beaches along the White and Barents seas: from highly exposed, reflective beaches with coarse-grained sands to sheltered, dissipative silty-sandy flats. For diatoms, the epipelic to epipsammic species abundance ratio was significantly correlated with the beach index and mean particle size, while neither α-diversity measures nor mean cell length were related to beach properties. In contrast, most of the characteristics of ciliate assemblages (diversity, total abundance and biomass, mean individual weight and percentage of karyorelictids) demonstrated a strong correlation to beach properties, remaining low at exposed beaches but increasing sharply in more sheltered conditions. β-diversity did not correlate with beach properties for either diatoms or ciliates. We suggest that wave action and sediment properties are the main drivers controlling the diversity and composition of the intertidal microbenthos. Diatoms and ciliates, however, demonstrated divergent response to these factors. Epipelic and epipsammic diatoms exhibited 2 different strategies to adapt to their environments and therefore were complementarily distributed along the environmental gradient and compensated for each other in diversity. Most ciliates demonstrated a similar mode of habitat selection but differed in their degree of tolerance. Euryporal (including mesoporal) species were relatively tolerant to wave action and therefore occurred under a wide range of beach conditions, though their abundance and diversity were highest in fine, relatively stable sediments on sheltered beaches, whereas the specific interstitial (i.e. genuine microporal) species were mostly restricted to only these habitats.

scholarly journals Colonisation of leaf litter by aquatic invertebrates in an Atlantic Forest stream

2014 ◽  
Vol 74 (2) ◽  
pp. 267-273 ◽  
Author(s):  
VC. Oliveira ◽  
EA. Gonçalves ◽  
RG. Alves
Keyword(s):  
Leaf Litter ◽  
Atlantic Forest ◽  
Riparian Vegetation ◽  
Aquatic Invertebrates ◽  
Dry Weight ◽  
Taxonomic Composition ◽  
Β Diversity ◽  
Forest Stream ◽  
Α Diversity ◽  
Abundance And Diversity

Riparian vegetation along streams in the Atlantic Forest in Brazil contributes to the formation of a highly heterogeneous leaf litter in streambeds. To investigate the structure and composition of the aquatic invertebrate community during the process of leaf decomposition of two plant species present along the banks of the stream studied, 21 plastic mesh bags containing 2.5g (dry weight) of leaf matter from each species (Alchornea glandulosa (Vell) and Cabralea canjerana End. and Poeppig), for a total of 5.0g, were placed in the streambed. Three bags were removed after 3, 6, 9, 12, 24, 48 and 96 days. The taxonomic density was negatively correlated with the remaining weight. The high density of collector organisms, such as Chironomidae, Oligochaeta and Amphipoda, on the last day of incubation, probably occurred due to the increased amount of fine organic matter in the more advanced decomposition stages. The highest α diversity (Shannon-Wiener) values were observed for the 3rd and 96th days of the experiment, while the β diversity values showed that these days presented the highest variation in the taxonomic composition, thus presenting a different faunistic composition. This study showed that the trophic structure and composition of aquatic invertebrates changes during the decomposition of leaf litter. The faunistic abundance and diversity observed in this study indicate that the entrance of material from plants growing along streams provides favorable conditions for the colonisation and establishment of invertebrates in lower-order streams, and thus points to the need to preserve riparian vegetation.

scholarly journals ГИГРОТОП И ТРОФОТОП БИОГЕОЦЕНОЗОВ СТЕПНОГО ПРИДНЕПРОВЬЯ КАК ДЕТЕРМИНАНТЫ β-РАЗНООБРАЗИЯ СООБЩЕСТВ ДОЖДЕВЫХ ЧЕРВЕЙ (LUMBRICIDAE)

2016 ◽  
Vol 6 (2) ◽  
pp. 188-222 ◽  
Author(s):  
A. V. Zhukov ◽  
D. B. Shatalin
Keyword(s):  
Forest Type ◽  
Steppe Zone ◽  
Forest Steppe ◽  
Ecological Groups ◽  
Β Diversity ◽  
Α Diversity ◽  
Abundance Variation ◽  
Abundance And Diversity ◽  
Forest Typology

<p>The role of the hygrotope and trophotope of the steppe Pridniprovie biogeoceonosis has been discussed in present article as being determinants of the β-diversity of earthworms (Lumbricidae) communities. Material has been colected to the period 1997-2015. 180 sample polygons have been studied which located in various types of biogeoceonosis. Biogeoceonotic characteristic of the sample polygons have been made on the basis of professor A.L. Belgard forest typology of a steppe zone of Ukraine. Earthworm communities of the steppe Pridniprovie have been established to be presented by 16 species. Hygrotopes, trophotopes and bitope ceonosis features have been shown to be able to explain 72.4 % of a communities’ abundance variation and 73.7 of their % α-diversity by means of second order model. Earthworm communities’ abundance reache their maximum values at a combination of conditions of humidity from hygromesophilous to hygrophilous and conditions of edaphotope trophicity from D<sub>c</sub> (linden oakwood) to D<sub>n </sub>(elm-ashen oakwood and alder forests). The maximum diversity of earthworm communities has been stated to be characteristic for a combination of mesohygrophilous conditions and a trophicity mode D<sub>c</sub>, that there corresponds to forest type a linden oakwood with aegopodium. The coenomorphic structure of the biogeocoenosis is statistically significant predictors of both abundance and α-diversity of earthworm communities. Earthworm communities of marsh monocoenosis, meadow-steppe amphicoenosis and steppe monocoenosis have been found as being characterised by minimum abundance and diversity. Moderate level abundance and diversity are characteristic for meadow-forest amphicoenosis, forest pseudomonocoenosis with elements of transformation to steppe and forest-steppe amphicoenosis. High levels of these indexes are typical for forest monocoenosis. Given other conditions of humidity and edaphotope trophicity being equal in forest monocoenosis abundance and diversity of earthworm communities will be higher than in other biogeocoenosis types. The MDM-analysis (<em>Multinomial</em><em> </em><em>Diversity</em><em> </em><em>Model</em>) reveals that habitats coenotic features define 12.61 % of all entropy of earthworm communities, hygrotopes – 24.12 %, trophotopes – 12.3 %. The square-law hygrotope member defines 10.93 %, and trophotope – 2.05 %. Hygrotope and trophotope interaction defines 1.53 % of entropy of earthworm communities. Sites (<em>α</em> -diversity) define 36.45 % of entropy. There are other factors which influence a diversity of earthworm communities besides a humidity, trophicity and habitat coenotic features. Steppe Pridniprovie earthworm complexes have been divided into ecological groups on the basis of relation to humidity (hygromorphes) and to edaphotope trophicity (trophocenomorphes). Earthworms hygromorphes are presented by xerophylous (2 species), mesophylous (9 species), hygrophylous (4 species), ultrahygrophylous (1 species). Trophocoenomorphes are presented by oligotrophocoenomorphes (1 species), oligomesotrophocoenomorphes (4 species)<em>, </em>mesotrophocoenomorphes (9 species)<em>, </em>megatrophocoenomorphes (2 species)<em>.</em></p><p> </p>

scholarly journals Taxonomic and Functional Characteristics of the Gill and Gastrointestinal Microbiota and Its Correlation with Intestinal Metabolites in NEW GIFT Strain of Farmed Adult Nile Tilapia (Oreochromis niloticus)

2021 ◽  
Vol 9 (3) ◽  
pp. 617
Author(s):  
Zhenbing Wu ◽  
Qianqian Zhang ◽  
Yaoyao Lin ◽  
Jingwen Hao ◽  
Shuyi Wang ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Oreochromis Niloticus ◽  
Nile Tilapia ◽  
High Throughput Sequencing ◽  
Gas Chromatography Mass Spectrometry ◽  
Gastrointestinal Mucosa ◽  
Gastrointestinal Microbiota ◽  
Linear Discriminant ◽  
Intestinal Microbes ◽  
Nile Tilapia Oreochromis Niloticus

The gill and gastrointestinal tract are primary entry routes for pathogens. The symbiotic microbiota are essential to the health, nutrition and disease of fish. Though the intestinal microbiota of Nile tilapia (Oreochromis niloticus) has been extensively studied, information on the mucosa-associated microbiota of this species, especially the gill and gastrointestinal mucosa-associated microbiota, is lacking. This study aimed to characterize the gill and gastrointestinal mucosa- and digesta-associated microbiota, as well as the intestinal metabolite profiles in the New Genetically Improved Farmed Tilapia (NEW GIFT) strain of farmed adult Nile tilapia by high-throughput sequencing and gas chromatography/mass spectrometry metabolomics. The diversity, structure, composition, and predicted function of gastrointestinal microbiota were significantly different across gastrointestinal regions and sample types (Welch t-test; p < 0.05). By comparing the mucosa- and digesta-associated microbiota, linear discriminant analysis (LDA) effect size (LEfSe) analysis revealed that Pelomonas, Ralstoniapickettii, Comamonadaceae, and Staphylococcus were significantly enriched in the mucosa-associated microbiota, whereas many bacterial taxa were significantly enriched in the digesta-associated microbiota, including Chitinophagaceae, Cetobacterium, CandidatusCompetibacter, Methyloparacoccus, and chloroplast (LDA score > 3.5). Furthermore, Undibacterium, Escherichia–Shigella, Paeniclostridium, and Cetobacterium were dominant in the intestinal contents and mucosae, whereas Sphingomonasaquatilis and Roseomonasgilardii were commonly found in the gill and stomach mucosae. The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt2) analysis revealed that the predictive function of digesta-associated microbiota significantly differed from that of mucosa-associated microbiota (R = 0.8152, p = 0.0001). In addition, our results showed a significant interdependence between specific intestinal microbes and metabolites. Notably, the relative abundance values of several potentially beneficial microbes, including Undibacterium, Crenothrix, and Cetobacterium, were positively correlated with most intestinal metabolites, whereas the relative abundance values of some potential opportunistic pathogens, including Acinetobacter, Mycobacterium, Escherichia–Shigella, Paeniclostridium, Aeromonas, and Clostridiumsensustricto 1, were negatively correlated with most intestinal metabolites. This study revealed the characteristics of gill and gastrointestinal mucosa-associated and digesta-associated microbiota of farmed Nile tilapia and identified a close correlation between intestinal microbes and metabolites. The results serve as a basis for the effective application of targeted probiotics or prebiotics in the diet to regulate the nutrition and health of farmed tilapia.

scholarly journals Dynamics of Diversity and Abundance of Sulfonamide Resistant Bacteria in a Silt Loam Soil Fertilized by Compost

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 699
Author(s):  
Hui Han ◽  
Mohan Bai ◽  
Yanting Chen ◽  
Yali Gong ◽  
Ming Wu ◽  
...  
Keyword(s):  
High Throughput ◽  
Relative Abundance ◽  
High Throughput Sequencing ◽  
Resistant Bacteria ◽  
Arable Soils ◽  
Soil Bacterial Communities ◽  
Sulfonamide Resistance ◽  
Loam Soil ◽  
Abundance And Diversity ◽  
Sulfonamide Resistance Genes

Although composting is effective in deactivating antibiotic substances in manure, the influence of compost fertilization on the occurrence and dissemination of antibiotic resistance in arable soils remains to be controversial. Herein, the abundance and diversity of two sulfonamide resistance genes (sul1 and sul2) in soil fertilized by compost spiked with two concentrations of sulfadiazine (1 and 10 mg kg−1) were studied intensively by qPCR and high throughput sequencing based on a two-month microcosm experiment. The concentration of sulfadiazine decreased rapidly after spiking from 25% at Day 1 to less than 2.7% at Day 60. Relative abundance of both sul1 and sul2 were significantly higher in soil amended with compost than the non-amended control at Day 1 and slightly decreased with incubation time except for sul2 in the S10 treatment. Soil bacterial communities were transiently shifted by compost fertilization regardless of the presence of sulfadiazine. Relative abundance of genera in three hubs positively interlinked with sul1 and sul2 were significantly higher in compost treated soil than the control at Day 1, 7 and 21, but not at Day 60. High throughput sequencing analyses revealed that most detected (>67% in relative abundance) sul1 and sul2 genotypes sharing >99% similarity with those found in gammaproteobacterial pathogens frequently were commonly present in compost and soil. These results indicated that compost fertilization might increase the abundance rather than diversity of sulfadiazine-resistant populations in soil, which may be facilitated by the presence of sulfadiazine.

scholarly journals Gut Microbiome Changes in Captive Plateau Zokors (Eospalax baileyi)

2021 ◽  
Vol 17 ◽  
pp. 117693432199635
Author(s):  
Daoxin Liu ◽  
Pengfei Song ◽  
Jingyan Yan ◽  
Haijing Wang ◽  
Zhenyuan Cai ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Gut Microbiome ◽  
High Throughput Sequencing ◽  
Tibet Plateau ◽  
Rrna Gene ◽  
Diversity Analysis ◽  
Bacterial Phyla ◽  
In Captivity ◽  
Relative Abundances ◽  
Plateau Zokor

Wild-caught animals must cope with drastic lifestyle and dietary changes after being induced to captivity. How the gut microbiome structure of these animals will change in response receives increasing attention. The plateau zokor ( Eospalax baileyi), a typic subterranean rodent endemic to the Qinghai-Tibet plateau, spends almost the whole life underground and is well adapted to the environmental pressures of both plateau and underground. However, how the gut microbiome of the plateau zokor will change in response to captivity has not been reported to date. This study compared the microbial community structure and functions of 22 plateau zokors before (the WS group) and after being kept in captivity for 15 days (the LS group, fed on carrots) using the 16S rRNA gene via high-throughput sequencing technology. The results showed that the LS group retained 973 of the 977 operational taxonomic units (OTUs) in the WS group, and no new OTUs were found in the LS group. The dominant bacterial phyla were Bacteroides and Firmicutes in both groups. In alpha diversity analysis, the Shannon, Sobs, and ACE indexes of the LS group were significantly lower than those of the WS group. A remarkable difference ( P < 0.01) between groups was also detected in beta diversity analysis. The UPGMA clustering, NMDS, PCoA, and Anosim results all showed that the intergroup difference was significantly greater than the intragroup difference. And compared with the WS group, the intragroup difference of the gut microbiota in the LS group was much larger, which failed to support the assumption that similar diets should drive convergence of gut microbial communities. PICRUSt revealed that although some functional categories displayed significant differences between groups, the relative abundances of these categories were very close in both groups. Based on all the results, we conclude that as plateau zokors enter captivity for a short time, although the relative abundances of different gut microbiota categories shifted significantly, they can maintain almost all the OTUs and the functions of the gut microbiota in the wild. So, the use of wild-caught plateau zokors in gut microbial studies is acceptable if the time in captivity is short.

Gut microbiome of the emerald ash borer, Agrilus planipennis Fairmaire, and its relationship with insect population density

2020 ◽  
Vol 96 (8) ◽  
Author(s):  
Judith Mogouong ◽  
Philippe Constant ◽  
Robert Lavallée ◽  
Claude Guertin
Keyword(s):  
Population Density ◽  
Gut Microbiome ◽  
Emerald Ash Borer ◽  
Agrilus Planipennis ◽  
Economic Damage ◽  
Taxonomic Structure ◽  
Rrna Gene ◽  
Local Conditions ◽  
Β Diversity ◽  
Α Diversity

ABSTRACT The gut microbial communities of beetles play crucial roles in their adaptive capacities. Environmental factors such as temperature or nutrition naturally affect the insect microbiome, but a shift in local conditions like the population density on a host tree could also lead to changes in the microbiota. The emerald ash borer (EAB), Agrilus planipennis Fairmaire, is an exotic wood borer that causes environmental and economic damage to ash trees in North America. This study aimed to describe the taxonomic structure of the EAB gut microbiome and explore its potential relationship with borer population size. The number of EAB adults collected per tree through a 75 km transect from an epicenter allowed the creation of distinct classes of population density. The Gammaproteobacteria and Ascomycota predominated in bacterial and fungal communities respectively, as determined by sequencing of the bacterial 16S rRNA gene and the fungal internal transcribed spacer ITS2. Species richness and diversity of the bacterial community showed significant dependence on population density. Moreover, α-diversity and β-diversity analysis revealed some indicator amplicon sequence variants suggesting that the plasticity of the gut microbiome could be related to the EAB population density in host trees.

The species evenness of “prey” bacteria correlated with Bdellovibrio-and-like-organisms (BALOs) in the microbial network supports the biomass of BALOs in a paddy soil

2020 ◽  
Vol 96 (12) ◽  
Author(s):  
Hang Qian ◽  
Chunli Hou ◽  
Hao Liao ◽  
Li Wang ◽  
Shun Han ◽  
...  
Keyword(s):  
Soil Properties ◽  
Paddy Soil ◽  
High Throughput Sequencing ◽  
Abiotic Factors ◽  
Negative Relationship ◽  
Sequencing Analysis ◽  
Nitrogen Use ◽  
Microbial Network ◽  
Α Diversity ◽  
Positive Effect

ABSTRACT To seek how soil biotic and abiotic factors which might shape the Bdellovibrio-and-like-organisms community, we sampled paddy soils under different fertilization treatments including fertilization without nitrogen (Control), the nitrogen use treatment (N) and the nitrogen overuse one (HNK) at three rice growing stages. The abundances of BALOs were impacted by the rice-growing stages but not the fertilization treatments. The abundances of Bdellovibrionaceae-like were positively associated with soil moisture, which showed a negative relationship with Bacteriovoracaceae-like bacteria. High-throughput sequencing analysis of the whole bacterial community revealed that the α-diversity of BALOs was not correlated with any soil properties data. Network analysis detected eight families directly linked to BALOs, namely, Pseudomonadaceae, Peptostreptococcaceae, Flavobacteriaceae, Sediment-4, Verrucomicrobiaceae, OM27, Solirubrobacteraceae and Roseiflexaceae. The richness and composition of OTUs in the eight families were correlated with different soil properties, while the evenness of them had a positive effect on the predicted BALO biomass. These results highlighted that the bottom-up control of BALOs in paddy soil at least partially relied on the changes of soil water content and the diversity of bacteria directly linked to BALOs in the microbial network.

scholarly journals Arthropod community structure in pastures of an island archipelago (Azores): looking for local–regional species richness patterns at fine-scales

2004 ◽  
Vol 94 (2) ◽  
pp. 111-121 ◽  
Author(s):  
P.A.V. Borges ◽  
V.K. Brown
Keyword(s):  
Species Richness ◽  
Regional Scale ◽  
Local Scale ◽  
Local Species Richness ◽  
Β Diversity ◽  
Arthropod Species ◽  
Α Diversity ◽  
Local Species ◽  
Richness Patterns

AbstractThe arthropod species richness of pastures in three Azorean islands was used to examine the relationship between local and regional species richness over two years. Two groups of arthropods, spiders and sucking insects, representing two functionally different but common groups of pasture invertebrates were investigated. The local–regional species richness relationship was assessed over relatively fine scales: quadrats (= local scale) and within pastures (= regional scale). Mean plot species richness was used as a measure of local species richness (= α diversity) and regional species richness was estimated at the pasture level (= γ diversity) with the ‘first-order-Jackknife’ estimator. Three related issues were addressed: (i) the role of estimated regional species richness and variables operating at the local scale (vegetation structure and diversity) in determining local species richness; (ii) quantification of the relative contributions of α and β diversity to regional diversity using additive partitioning; and (iii) the occurrence of consistent patterns in different years by analysing independently between-year data. Species assemblages of spiders were saturated at the local scale (similar local species richness and increasing β-diversity in richer regions) and were more dependent on vegetational structure than regional species richness. Sucking insect herbivores, by contrast, exhibited a linear relationship between local and regional species richness, consistent with the proportional sampling model. The patterns were consistent between years. These results imply that for spiders local processes are important, with assemblages in a particular patch being constrained by habitat structure. In contrast, for sucking insects, local processes may be insignificant in structuring communities.

A quantitative null model of additive diversity partitioning: examining the response of beta diversity to extinction

Paleobiology ◽  
2007 ◽  
Vol 33 (1) ◽  
pp. 116-124 ◽  
Author(s):  
Karen M. Layou
Keyword(s):  
Null Model ◽  
Sampling Strategy ◽  
Diversity Partitioning ◽  
Opposite Pattern ◽  
Β Diversity ◽  
Α Diversity ◽  
Before And After ◽  
Four Levels ◽  
Total Diversity ◽  
Selective Extinction

Paleobiological diversity is often expressed as α (within-sample), β (among-sample), and γ (total) diversities. However, when studying the effects of extinction on diversity patterns, only variations in α and γ diversities are typically addressed. A null model that examines changes in β diversity as a function of percent extinction is presented here.The model examines diversity in the context of a hierarchical sampling strategy that allows for the additive partitioning of γ diversity into mean α and β diversities at varying scales. Here, the sampling hierarchy has four levels: samples, beds, facies, and region; thus, there are four levels of α diversity (α1, α2, α3, α4) and three levels of β diversity (β1, β2, and β3). Taxa are randomly assigned to samples within the hierarchy according to probability of occurrence, and initial mean α and β values are calculated. A regional extinction is imposed, and the hierarchy is resampled from the remaining extant taxa. Post-extinction mean α and β values are then calculated.Both non-selective and selective extinctions with respect to taxon abundance yield decreases in α, β, and γ diversities. Non-selective extinction with respect to taxon abundance shows little effect on diversity partitioning except at the highest extinction magnitudes (above 75% extinction), where the contribution of α1 to total γ increases at the expense of β3, with β1 and β2 varying little with increasing extinction magnitude. The pre-extinction contribution of α1 to total diversity increases with increased probabilities of taxon occurrence and the number of shared taxa between facies. Both β1 and β2 contribute equally to total diversity at low occurrence probabilities, but β2 is negligible at high probabilities, because individual samples preserve all the taxonomic variation present within a facies. Selective extinction with respect to rare taxa indicates a constant increase in α1 and constant decrease in β3 with increasing extinction magnitudes, whereas selective extinction with respect to abundant taxa yields the opposite pattern of an initial decrease in α1 and increase in β3. Both β1 and β2 remain constant with increasing extinction for both cases of selectivity. By comparing diversity partitioning before and after an extinction event, it may be possible to determine whether the extinction was selective with respect to taxon abundances, and if so, whether that selectivity was against rare or abundant taxa.Field data were collected across a Late Ordovician regional extinction in the Nashville Dome of Tennessee, with sampling hierarchy similar to that of the model. These data agree with the abundant-selective model, showing declines in α, β, and γ diversities, and a decrease in α1 and increase in β3, which suggests this extinction may have targeted abundant taxa.

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