Long-term sequelae of severe acute respiratory coronavirus-2 (SARS-CoV-2) infection may include increased incidence of diabetes. Here we describe the temporal relationship between new type 2 diabetes and SARS-CoV-2 infection in a nationwide database. We found that while the proportion of newly diagnosed type 2 diabetes increased during the acute period of SARS-CoV-2 infection, the mean proportion of new diabetes cases in the 6 months post-infection was about 83% lower than the 6 months preinfection. These results underscore the need for further investigation to understand the timing of new diabetes after COVID-19, etiology, screening, and treatment strategies.

Altica's location in the Patlachique Range, 10 km away from the Otumba obsidian source, suggests its potential role in the distribution of Otumba obsidian. Altica may have been an important Formative middleman and processing site for obsidian exchange within the Basin of Mexico. To the south, Coapexco's position along a natural, restricted inlet to the Basin of Mexico may have enabled it to function as a node for pooling and distributing material into the Basin. This paper combines geochemical sourcing and technological data drawn from several Early and Middle Formative obsidian assemblages to reconstruct the movement of obsidian in this period to identify obsidian sources and consumption sites. In doing so, the paper assesses the role that intermediary sites like Altica and Coapexco could have played in the processing and distribution of obsidian into more distant consumption sites.

The excellent fossil record of the past few million years, combined with the overwhelming similarity of the biota to extant species, provides an outstanding opportunity for understanding paleoecological and macroevolutionary patterns and processes within a rigorous biological framework. Unfortunately, this potential has not been fully exploited because of lack of well-sampled time series and adequate statistical analysis. Nevertheless, four basic patterns appear to be of general significance. First, a major pulse of extinction occurred 1–2 m.y. ago in many ocean basins, more or less coincident with the intensification of glaciation in the Northern Hemisphere. Rates of origination also increased greatly but were more variable in magnitude and timing. The fine-scale correlation of these evolutionary events with changes in climate is poorly understood. Similar events probably occurred on land but have not been tested adequately. Second, rates of origination and extinction in the oceans waned after the pulse of extinction, especially during the past 1 m.y. Thus, most marine species originated long before the Pleistocene under very different environmental circumstances, suggesting that they are “exapted” rather than adapted to their present ecological circumstances. The same may be true for many terrestrial groups, but not for the mammals or fresh-water fishes that have continued to undergo speciation throughout the Pleistocene. Third, community membership of late Pleistocene coral reef communities was more stable than expected by chance. These are the only paleoecological data adequate to test hypotheses of community stability, so that we do not know whether community structure involving other taxa or environments typically reflects more than the collective behavior of individual species distributions. Regardless, the strong evidence for nearly universal exaptation of ecological characteristics argues strongly against ideas of coevolution of species in communities. Finally, ecological communities were profoundly altered by human activities long before modern ecological studies began. Holocene paleontological, archeological, and historical data constitute the only ecological baseline for “pristine” ecological communities before significant human disturbance. Holocene records should be much more extensively used as a baseline for Recent ecological studies and for conservation and management.

The reliability of any survey of biodiversity through geologic time depends on the rigor and consistency by which taxa are recognized and samples are identified. The main goal of the Neogene Marine Biota of Tropical America (‘NMITA’) project is to create an online biotic database (http://nmita.geology.uiowa.edu) containing images and synoptic taxonomic information that are essential to collecting and disseminating high-quality taxic data. The database consists of an inventory of taxa collected as part of several large multi-taxa fossil sampling programs designed to assess marine biodiversity in tropical America over the past 25 m.y. In the first phase of the project, data for ~1,300 taxa and ~3,800 images are currently being entered into a relational database management system on an IBM RS6000 at the University of Iowa. Eleven taxonomic groups are represented: bivalves, gastropods (muricids, marginellids, strombinids), bryozoans (cheilostome, cyclostome), corals (azooxanthellate, zooxanthellate), benthic foraminifers, ostracodes, fish. The lowest taxonomic rank is species (genera/subgenera in mollusks) and the highest is family. Data that are collected and displayed on taxon pages include: (1) taxonomic authorship, synonyms, type specimens, and diagnostic morphologic characters; (2) images of representative specimens and associated museum catalog and measurement data; (3) distributional information including geologic ages, stratigraphic units, and spatial locations; and (4) higher level classification (genera and families) and bibliographic information. Illustrated glossaries of morphologic terms, character matrices, and identification tools are being developed for corals and mollusks. Interactive geographic maps and stratigraphic columns have been designed to provide information about taxa collected at different locations.

Caribbean coral reef communities were restructured by episodes of accelerated biotic change during the late Oligocene/early Miocene and the late Pliocene/early Pleistocene. However, rigorous description of the effects of rapid biotic change is problematic because preservation and exposure of coral-bearing deposits is not consistent in all stratigraphic intervals. In the Caribbean, early and middle Miocene exposures are more rare than late Miocene and Pliocene exposures. One exception is the late early to early middle Miocene Tamana Formation of Trinidad, and old and new collections from this unit were studied to determine the timing of recovery after the Oligocene/Miocene transition. A total of 41 species of zooxanthellate corals were recovered from the unit, including 21 new records. Within these assemblages, species first occurrences outnumber species last occurrences by a factor of four (31 first occurrences and eight last occurrences). The extension of the stratigraphic ranges of species previously first recorded in Pliocene sediments has reduced an apparent Pliocene pulse of origination, indicating that the Pliocene/Pleistocene transition was largely a result of accelerated extinction against a background of near-constant origination. The fact that few species last occur in the Tamana fauna indicates that the Oligocene/Miocene transition was complete by the end of the early Miocene.

Statistical analyses of occurrence data derived from new collections through scattered Caribbean sections indicate that increased speciation preceded a pulse of extinction during regional turnover of the Caribbean reef coral fauna in Plio-Pleistocene time. The data are based on samples that were newly collected and identified to species using standardized procedures. Age-dates were assigned using high-resolution chronostratigraphic methods. The results show that coral species with a wide range of ecological traits originated and were added to the species pool as much as 1–2 million years before extinction peaked at the end of the turnover interval. Local assemblages consisted of a mix of extinct and living species, which varied in composition but not in richness. Extinction was selective and resulted in a faunal shift to the large, fast-growing species that dominate Caribbean reefs today. The unusual relationship between origination and extinction may have been caused by changes in oceanic circulation associated with emergence of the Central American Isthmus, followed by the onset of Northern Hemisphere glaciation. The pattern of origination preceding extinction may have been responsible for the stability of reef ecosystems during the intense climatic fluctuations of the late Pleistocene, and for the composition and structure of modern Caribbean reef ecosystems.

This study represents a preliminary analysis of variation in size and shape in a large and diverse molluscan clade, the Strombina group, over the past 20 million years. Restored height and width were measured on 5,099 individuals of 72 species and 5 genera. Size was estimated by adding height and width, and shape was estimated by dividing height by width. Patterns of variation were analyzed quantitatively among species, subgenera, and genera using univariate statistical tests comparing means and variances and linear regression.

Results of univariate tests show that both shape and size vary among species within subgenera (the specific level) and among genera (the generic level). However, only shape varies among subgenera within genera (the subgeneric level). Regression analyses for each species show that the relationship between height and width is linear, indicating that growth is never allometric with respect to these characters. Because of this nonallometric growth, rates of shape relative to size change can never vary, imposing a severe constraint on shape change and, in turn, shape evolution. Regression models for species within subgenera have equal slopes but differ slightly in intercept. Subgeneric models differ more in intercept. Generic level models differ in slope. These results suggest that formation of species within subgenera primarily involves extension or contraction of trajectories between height and width within species (=static vectors), resulting in size change without shape change. Shape change is more important in the evolution of higher categories.

To examine overall morphologic change in the clade through time, mean sizes and shapes of species were analyzed using nonparametric statistics. Only a slight tendency exists within the clade for increase in species size, and this tendency is best expressed within two species-rich subgenera having long stratigraphic ranges. No directional trends exist for change in species shape. No relationship is found between species size and probability of speciation or extinction, or between species size and species duration, thus negating the role of species selection. Nevertheless, species are smaller in size in the northern Caribbean, a region characterized by extreme fluctuations in temperature. Larger species occurred only after a taxonomic radiation in the eastern Pacific, a more restricted region possibly characterized by reduced environmental disturbance. During this radiation, normal patterns of morphologic change associated with speciation appear to have been disrupted.

To document evolutionary patterns in late Cenozoic Caribbean reef corals, we compiled composite stratigraphic ranges of 49 genera and 175 species using Neogene occurrences in the Cibao Valley sequence of the northern Dominican Republic and faunal lists for 24 Miocene to Recent sites across the Caribbean region. This new compilation benefits in particular from increased sampling at late Miocene to early Pleistocene sites and from increased resolution and greater taxonomic consistency provided by the use of morphometric procedures in species recognition.

Preliminary examination and quantitative analysis of origination and extinction patterns suggest that a major episode of turnover took place between 4 and 1 Ma during Plio-Pleistocene time. During the episode, extinctions were approximately simultaneous in species of all reef-building families, except the Mussidae. Most strongly affected were the Pocilloporidae (Stylophora and Pocillopora), Agariciidae (Pavona and Gardineroseris), and free-living members of the Faviidae and Meandrinidae. At the genus level, mono- and paucispecific as well as more speciose genera became regionally extinct. Many of the extinct genera live today in the Indo-Pacific region, and some are important components of modern eastern Pacific reefs. Global extinctions were concentrated in free-living genera. During the turnover episode, no new genera or higher taxa arose. Instead, new species originated within the surviving Caribbean genera at approximately the same time as the extinctions, including many dominant modern Caribbean reef-building corals (e.g., Acropora palmata and the Montastraea annularis complex).

Excluding this episode, the taxonomic composition of the Caribbean reef-coral fauna remained relatively unchanged during the Neogene. Minor exceptions include: 1) high originations in the Agariciidae and free-living corals during late Miocene time; and 2) regional or global extinctions of several important Oligocene Caribbean reef builders during early to middle Miocene time.

The megafauna and associated behavioral traces of two deep-sea benthic environments, the central Arctic and Antarctic, with a surface primary productivity differential of 104 were compared to assess the role of food availability in foraging strategy and community structure. Bottom photographs, analyzed for megafauna and trace density and diversity at comparable depths in the Arctic Canada Basin and the Antarctic Bellingshausen Basin, indicated that trace frequency was inversely proportional to organism density but that trace diversity directly reflected organism diversity. Those traces identified in the fossil record to represent efficient foraging strategies, i.e., the Nereites facies, were conspicuously absent at all depths in the Arctic and present at all depths in the Antarctic, in contradiction of the paradigm of increasing behavioral complexity and sediment exploitation as food availability decreases. Presence or absence of surface-grazing organisms seems to exert a greater influence on trace diversity than depth or nutrient supply. Trace density, however, may reflect episodic sedimentation events which intermittently influence the deep-sea trophic regime.

Global biodiversity dynamics result in large-scale patterns of change in the variety of life on earth. One deceptively simple measure of global biodiversity is the total count of species or supraspecific taxa that have been described from each subinterval of the Phanerozoic record. These tallies usually are obtained from data compilations based on extensive literature searches supplemented with examination of collections in museums (Sepkoski 1993; Alroy et al. 2001). Such measures of global biodiversity dynamics are probably not meaningless, but it is difficult to understand what they mean. The number of taxa alive on Earth at any one time is a function of innumerable ecological factors acting at the full range of temporal and spatial scales (Willis and Whittaker 2002). Changes in global richness might result from increasing local richness as local communities become more complex (Valentine 1969; Bambach 1977). At the regional scale, changing oceanographic conditions, climate, and the relative positions of continents and shallow seas might alter global taxonomic diversity by changing the size and arrangement of biogeographic units (Valentine 1970). Therefore, the best hope for understanding global diversity patterns is to collect information on local assemblages. These hierarchically organized data can then be integrated to test alternate hypothetical mechanisms of change. Data compiled as the endpoints of stratigraphic or geographic ranges are useless for this purpose. This has been known at least since Bambach (1977) explored patterns of change in alpha diversity of level-bottom marine communities.

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.

We analyze a new compilation of Neogene to Recent (22-0 Ma) Caribbean coral occurrences to determine how ecological and life history traits at the population level affect long-term evolutionary patterns. The compilation consists of occurrences of 175 species and 49 genera in one continuous (> 5 m.y.) sequence and 22 scattered sites across the Caribbean region. Previous study of evolutionary rates using these data has shown that both extinction and origination were accelerated between 4 and 1 Ma, resulting in large-scale faunal turnover. Categories for three morphological and two reproductive variables (colony size, colony shape, and corallite size; and sex, and mode of embryonic development; respectively) are assigned to each species in the compilation. Comparisons of the ecological variables with evolutionary rates using randomization procedures and modified analysis of variance show that only colony size was strongly related to rates of extinction and origination during either normal background times or times of accelerated extinction. Extinction rates were lower in species with large colonies, because species with small massive colonies tend to live in small, short-lived populations with highly fluctuating recruitment rates. During turnover, extinction rates increased disproportionately in species with small colonies. Origination rates are found to be less related to ecological variables, although species with small massive colonies originated at higher rates prior to turnover.

Accelerated turnover may have therefore involved an increase in local population extinction rates that caused increased rates of both species extinction and origination across the entire fauna. Since extinction rates accelerated disproportionately with respect to colony size, the overall result was a relative increase in species with large colonies. After severe disturbance, one might expect that populations of species with large colonies and high rates of fragmentation would be more likely to escape extinction, because of larger population sizes, longer generation times, and more constant rates of population increase. The modern Caribbean reef-coral fauna is therefore structured by large, long-lived colonies that are robust to regional environmental change. Many of the very taxa that allowed reef communities to escape collapse in the past are declining today in response to anthropogenic disturbances, suggesting that Caribbean reef communities may be less resilient in the future in response to ongoing environmental perturbations.

Morphologic discrimination of species of scleractinian reef corals has long been plagued by a shortage of independent characters and by high ecophenotypic plasticity. Because of these two factors, many species appear to intergrade morphologically. We outline a newly developed protocol for the morphometric recognition of species, which uses size and shape coordinates derived from landmark data. The landmarks consist of spatially homologous points digitized in three dimensions on upper calical surfaces. The approach is more powerful than linear measurements at detecting subtle distinctions among species; and the distinctions are easy to visualize and interpret biologically, which increases the accuracy and resolution of subsequent phylogenetic and large-scale faunal analyses.

As an example, we distinguish morphospecies in collections of Porites made at three Caribbean locations. Size and shape coordinates are analyzed using principal component analysis, average linkage cluster analysis, and a series of iterative discriminant analyses. Positions of different corallites from the same colonies are examined on cluster dendrograms to determine cutoffs for group recognition, and discriminant classifications for different corallites from the same colonies are compared to maximize group assignments. The results yield seven morphospecies, which are generally in 90% agreement with classification of the same animals using allozyme electrophoresis. Measures of corallite size and the relative heights and locations of the pali and septal denticles all reveal unique patterns of variation among morphospecies.

Caribbean reefs underwent significant biotic change during the Late Oligocene and Early Miocene. This was a critical time in the evolution of the modern Caribbean fauna characterized by increasing endemism resulting from regional extinction of lineages that survive in the modern Indo-Pacific. An understanding of the dynamics and potential causes of the Oligocene/Miocene transition, however, is hampered by the relative lack of well-preserved Oligocene to early Miocene coral faunas in the Caribbean. Here we examine new exposures in the Culebra Formation of Panama that contain a well-preserved coral fauna of Early Miocene age. Taxonomic, stratigraphic, and paleoecologic study of the Culebra Formation exposed along the Gaillard Cut of the Panama Canal allows us to infer the paleoenvironments and reef coral communities from the Panama Canal Basin during this critical interval. The Culebra Formation consists of a deepening upward sequence with shallow-lagoon sediments at the base, overlain by fringing reef facies in the middle of the section, and open-shelf to bathyal facies at the top of the section. We recovered 31 species of reef corals from a combination of new and old collections. Comparison of our collections with other Late Oligocene to Middle Miocene reef coral assemblages confirms that there was a major faunal turnover after deposition of the Upper Oligocene Antigua Formation. This turnover consisted of a large number of extinctions followed by an increased rate of first occurrences so that regional diversity did not change appreciably. Improved stratigraphic resolution at this and other Caribbean localities is required to understand fully the dynamics of change during the Oligocene/Miocene transition.