Body Size, Habitat, and History: Island-shrews of Puerto Rico and Cuba

A new study by Turvey and colleagues (2025), just published in iScience, re-examines the Puerto Rican island-shrew Nesophontes edithae from the classic Morovis caves using precise radiocarbon and U-series dating, morphometrics of jaws and limb bones, and carbon-isotope analyses of tooth enamel to document an earlier, smaller morph in more open, savanna-like habitats and a later, larger morph in closed forests between about 50,000 years ago and the mid-Holocene. Recent work on the Puerto Rican Nesophontes therefore complements, rather than contradicts, the Cuban record, and together both datasets help refine our view of how this extinct group lived and evolved in the Greater Antilles since the Ice Age.

A brief introduction to an odd little mammal

Nesophontes were small, shrew-like mammal endemic to the Greater Antilles. These 'island-shrews' belonged to the order Eulipotyphla, the same broader group that includes living shrews, moles, hedgehogs, and their relatives. Fossils show that Nesophontes were likely nocturnal, semi-fossorial insectivores, and possibly venomous. Each large island had its own endemic forms: three species are currently recognized in Cuba (N. micrus, N. major, N. longirostris), three in Hispaniola (N. paramicrus, N. hypomicrus, N. zamicrus), one in Puerto Rico (N. edithae), and one in the Cayman Islands (N. hemicingulus).

The history of their discovery is closely tied to the American Museum of Natural History in New York. Harold E. Anthony described Nesophontes edithae in 1916 from material collected near Morovis, Puerto Rico. The type specimen was found in Cueva Clara by his wife, Edith I. Anthony, whose name the species still carries. In 1917, Glover M. Allen described N. micrus from material collected in Matanzas by Carlos de la Torre. Later, Anthony described N. longirostris from a cave in Daiquirí, southeastern Cuba. These early discoveries laid the groundwork for more than a century of work on this unusual mammal.

In recent years, new biomolecular methods have greatly improved our understanding of Nesophontes evolution. Collagen sequence analyses (proteomics) published by Buckley et al. (2020) helped clarify the relationships within the group and re-confirmed that Nesophontes and the living solenodons form sister lineages within Solenodontidae-Solenodonota. For the Cuban material, that molecular work showed that most specimens fall into two main collagen lineages corresponding to a smaller morph N. micrus and a larger morph N. major, with the large, long-snouted N. longirostris forming a close relative of N. major rather than a separate deep lineage. These proteomic results provide an independent framework that is consistent with, and helps to refine, the species limits later formalized on morphological grounds by Orihuela (2023).

Against this background, two recent lines of research help refine the picture: Turvey and colleagues’ 2025 study of N. edithae in Puerto Rico, and Orihuela's 2023 revision of the Cuban species.

Nesophontes edithae holotype AMNH 14174 (female?)
From original photograph published by Anthony (1916).

The Puertorican story: one species, two sizes phases in time

Turvey et al. focus on a single taxon, N. edithae, in one restricted landscape in northern Puerto Rico (the Morovis caves). Their core result is that the striking size variation observed in Puerto Rican Nesophontes corresponds to two allochronic size morphs rather than to coexisting “small” and “large” individuals of the same population. Using morphometrics of mandibles and femora, they show that material from the upper layer of Nesophontes II Cave represents a single, distinctly large and robust morph, whereas material from the lower layer and from Nesophontes Cave represents a smaller morph, with each stratigraphic unit showing unimodal size distributions. Mean body mass is estimated at about 200 g for the large Holocene morph and ~ 83–98 g for the smaller Late Pleistocene morph, based on established regressions for eulipotyphlan molar dimensions.

The Puerto Rican material is firmly anchored in time. Radiocarbon dating of associated charcoal and U-series dating of bones show that the small morph spans at least ~50,000–16,000 years before present, whereas the large morph appears rapidly around 13,500 years ago and continues into the middle Holocene. Turvey et al. then add stable carbon isotopes from tooth enamel to this framework. The small, older morph has more positive δ¹³C values (mean −7.9‰), while the large, younger morph shows more negative values (mean −10.3‰). This difference is interpreted in terms of habitat: the small morph is associated with more open savanna-type environments rich in C₄ grasses, typical of the Late Pleistocene, whereas the large morph is associated with more closed, C₃-dominated forests typical of Holocene Puerto Rico. In this setting, size change is explicitly tied to a well-constrained climatic and vegetational transition. Because the bones have lost almost all organic content, neither collagen nor DNA could be recovered, and delicate elements such as pelvises were not analyzed molecularly or morphologically; their conclusions rest on stratigraphy, morphometrics, and enamel δ¹³C.

Choate and Birney’s classic paper, “Sub-recent Insectivora and Chiroptera from Puerto Rico, with the description of a new bat of the genus Stenoderma”, was published in 1968 in the Journal of Mammalogy. In that work they already noted that the marked size variation in Puerto Rican Nesophontes could reflect differences between cave assemblages of different ages (a “chrono-temporal” effect), rather than only individual or sexual variation. Turvey et al.’s new study effectively tests and refines that idea. By tying the small and large N. edithae morphs to separate, radiometrically dated Late Pleistocene and Holocene layers at Morovis, and showing that they do not overlap in time while also occupying different isotopic (habitat) niches, their results are consistent with the chrono-temporal interpretation outlined by Choate and Birney, but go further by rejecting the need for strong sexual dimorphism and by quantifying the timing and environmental context of the size shift.

The Cuban story: three species, each with incipient sexual dimorphism

By contrast, recent work on Cuban taxa (Orihuela et al., 2020), and specially the most recent revision (Orihuela 2023) has been explicitly island-wide and taxonomic in scope. Following one species through time at a single locality, that study assembled and statistically analysed large numbers of Nesophontes specimens—thousands of bones—from several carefully radiocarbon dated beds and specimens. Where layers could be assigned to the same age, specimens from those single-age horizons were compared directly. Those results were then contrasted with material from older and younger units in the same sites, and finally with samples from other regions of the island, but in some cases precise chronological control was not available. This stepwise approach allowed Orihuela to ask both how many species were present and how much variation occurred within each species across space and, where possible, through time.

Morphologically, the Cuban revision re-examines N. micrus, N. major, and N. longirostris based on a large sample integrating cranial, dental, petrosal, endocranial, and postcranial measurements. Statistical distributions of key variables such as maxillary toothrow length, breadth across canines, and femoral length are distinctly bimodal when all Cuban Nesophontes are pooled, and do not fit a single Gaussian population, supporting the recognition of at least two Cuban species rather than extreme intraspecific variation. Within this framework, body mass is estimated with several independent methods (molar area, cranial length, limb shaft circumference). For N. micrus, the range is ~37–56 g, and for N. major ~33–67 g, with N. longirostris slightly larger than N. major. These values are consistent with a clade of small, mouse-to-rat sized insectivores and fall below the values obtained for N. edithae in Puerto Rico, in line with the long-standing view that N. edithae was among the largest members of the genus.

In recent years, new biomolecular methods have also improved our understanding of Nesophontes evolution. Collagen sequence analyses (proteomics) published by Buckley et al. (2020), with Orihuela as co-author, clarified relationships within the group and confirmed that Nesophontes and the living solenodons form sister lineages. For the Cuban material, that molecular work showed that most specimens fall into two main collagen lineages corresponding to N. micrus and N. major, with the large, long-snouted N. longirostris closely allied to N. major rather than representing a completely separate deep lineage. These proteomic results provide an independent framework that is consistent with, and helps to refine, the species limits formalized on morphological grounds by Orihuela (2023).

Both studies also incorporate stable isotopes, but with different substrates, resolutions, and goals. Turvey et al. analyse δ¹³C in tooth apatite, which is robust to diagenesis and directly reflects the carbon-isotope composition of plants at the base of the local food web. Their key signal is a statistically significant shift in enamel δ¹³C between the small and large morphs that closely tracks the Pleistocene–Holocene transition from open to closed habitats. Isotopes in this case are used primarily to support a chronoclinal habitat shift already suggested by the dated stratigraphy.

In Cuba, the isotopic work is an initial attempt to understand diet and habitat in two species that are already known to be sympatric (Orihuela et al., 2020; Orihuela, 2023). Collagen δ¹³C and δ15N values are reported for N. micrus, N. major, and Solenodon cubanus from several well-dated Holocene cave deposits. Carbon values for Cuban Nesophontes span roughly −20‰ to −9‰, implying a mixture of C₃ and C₄ resources, and hence use of both open and closed environments. When plotted against body size and compared with Solenodon, the data suggest that N. major was slightly more associated with shaded, closed habitats (more negative δ¹³C), whereas N. micrus tended toward more open grassland–savanna conditions (more positive δ¹³C). At the same time, the isotope data indicate that both species foraged across a heterogeneous landscape of mixed and riverine woodland interspersed with more open areas. he results presented by Orihuela et al. (2020) and Orihuela (2023) are best regarded as a first baseline for Nesophontesisotope ecology in Cuba, to be refined as larger and better time-constrained samples become available; the aim was to establish this baseline to be built upon later, rather than to provide a definitive picture.

Paleoart reconstruction of Nesophontes major by Adrian Tejedor (C)

Different islands, complementary stories?

The two papers reach different conclusions about the role of sexual dimorphism in explaining size variation, but under different empirical conditions. In Puerto Rico, Turvey et al. test the long-standing hypothesis that the size disparity in N. edithae reflects strong sexual size dimorphism. They find that within each stratigraphic unit the size distributions of their largest measurement series are unimodal, and that small and large morphs never co-occur in the same temporal horizon at the Morovis sites. Combined with the isotopic and chronological evidence for distinct palaeoenvironments, they interpret the small and large morphs as allochronic populations tied to different climatic and habitat regimes, and conclude that their results refute the earlier hypothesis of pronounced sexual dimorphism in Puerto Rican nesophontids. Because pelvises and other delicate postcranial elements are not preserved in sufficient numbers or investigated, their analysis appropriately does not include on pelvic anatomy.

In Cuba, the situation is more complex. The revision shows that N. micrus and N. major form two morphometrically distinct clusters at the species level, but also that within each species there is low, but detectable, morphometric variation that is consistent with modest sexual size dimorphism. Finite mixture analyses of selected cranial, petrosal, humeral, and femoral measurements suggest two overlapping subgroups per species with an average male:female ratio of about 1:1.03, similar to values reported for N. edithae femora by McFarlane (1999). Pelvic morphology shows additional differences: more robust morphotypes have more curved sciatic notches and thicker, rounder and more angost pubic symphyses than gracile morphotypes, patterns interpreted as male and female respectively. These pelvic contrasts parallel differences in humeral and femoral robustness: robust morphotypes have thicker shafts, larger femoral heads and more strongly marked muscle attachment scars, whereas gracile morphotypes are smaller and lighter. Orihuela (2023) emphasizes that these differences are modest and that Cuban Nesophontes “do not display substantial sexual size dimorphism” overall, with sex-linked variation treated as just one part of the size range within each species. This naturally raises the question of which morphotype is male and which is female: Anthony (1916) assumed the larger form was male, but the Cuban data do not require that, and the reverse could just as well be true. Resolving this would require independent sexing: for example, genetic or chromosomal markers in suitable material, to see who caries the female or male chromosomes. 

Chronologically, the Puerto Rican and Cuban records complement each other. Turvey et al. work with a vertical, high-resolution Late Pleistocene–Holocene sequence at a single locality, and are able to document a relatively rapid size shift (on the order of three millennia) against a well-dated climatic backdrop. The Cuban data, in contrast, are dominated by late Holocene cave assemblages spanning roughly the last two millennia, with emphasis on spatial variation among sites and co-occurrence of species rather than on long-term chronoclinal trends. The isotope section of the Cuban work explicitly highlights temporal averaging and seasonal effects as potential complications, and calls for larger, stratigraphically constrained datasets to explore diachronic patterns in more detail.

Taken together, both studies point to a picture in which Nesophontes were neither ecologically rigid nor morphologically static. In Puerto Rico, a single lineage (or closely related lineages) shows large, environmentally correlated changes in body size and habitat use through the Late Quaternary, without evidence for strong sexual dimorphism driving the pattern. In Cuba, two smaller-bodied species coexist in Holocene landscapes, partitioning habitats and resources in subtler ways, with only modest sex-linked size differences within each taxon. 

The methods are also complementary: Turvey et al. combine enamel isotopes with precise dating to frame a local chronoclinal story, while the Cuban revision uses extensive morphometrics, pelvic anatomy, collagen isotopes, and broader geographic coverage to refine taxonomy and ecological reconstruction.

Taken together, these differences also remind us that Cuba and Puerto Rico do not share the same geological or environmental history. Island size, topography, climate trajectories, and habitat mosaics have all differed through the Late Quaternary, and it is plausible that Nesophontes did not play exactly the same ecological roles or follow identical evolutionary paths on each island. At the same time, the present records are still incomplete and unevenly sampled, so these contrasts are best viewed as indications that island context matters for Nesophontes evolution, rather than as proof of any single evolutionary scenario. Future work will be needed to test how far these island-specific patterns really extend.

Conclusions

The key message is that these “island shrews” were dynamic components of Antillean ecosystems, tracking environmental change over tens of thousands of years and partitioning habitats at fine scales, long before human arrival. The Puerto Rican and Cuban records do not contradict each other; rather, they describe different facets of the same lineage’s history under different island contexts, and both leave open important questions that will be addressed as new material and methods become available.

Cited Literature

Turvey, S. T., Lamb, A. L., Rye, P., Vale Nieves, A., Cooper, J. H., & van Calsteren, P. 2025. Major body size change in an extinct tropical island mammal associated with glacial–interglacial environmental shifts. iScience 113968, in press. https://doi.org/10.1016/j.isci.2025.113968 Cell+1

Orihuela León, J. 2023. Revision of the extinct island-shrews Nesophontes (Mammalia: Eulipotyphla: Nesophontidae) from Cuba. Journal of South American Earth Sciences 130, 104544. https://doi.org/10.1016/j.jsames.2023.104544ResearchGate

Orihuela, J., Pérez Orozco, L., Álvarez Licourt, J. L., Viera Muñoz, R. A., & Santana Barani, C. 2020. Late Holocene land vertebrate fauna from Cueva de los Nesofontes, western Cuba: Stratigraphy, chronology, diversity, and paleoecology. Palaeontologia Electronica 23(3), a57. https://doi.org/10.26879/995 Palaeontologia Electronica

Buckley, M., Harvey, V. L., Orihuela, J., Mychajliw, A. M., Keating, J., Almonte Milán, J. N., Lawless, C., Chamberlain, A. T., Egerton, V. M., & Manning, P. L. 2020. Collagen sequence analysis reveals evolutionary history of extinct West Indies Nesophontes (“island-shrews”). Molecular Biology and Evolution 37(10), 2931–2943. https://doi.org/10.1093/molbev/msaa137 PMC

Choate, J. R., & Birney, E. C. 1968. Sub-Recent Insectivora and Chiroptera from Puerto Rico, with the description of a new bat of the genus Stenoderma. Journal of Mammalogy 49(3), 400–412. Nature

McFarlane, D. A. 1999. A note on dimorphism in Nesophontes edithae (Mammalia: Insectivora), an extinct island-shrew from Puerto Rico. Caribbean Journal of Science 35, 142–143. BioMed Central

Anthony, H. E. 1916. Preliminary diagnosis of an apparently new family of insectivores. Bulletin of the American Museum of Natural History 35, 725–728. 

A Proto-Caribbean Record of the Weissert Event from Cuba

In the Sierra de los Órganos in western Cuba, the steep limestone hills preserve sediments that accumulated on the floor of the ancient Caribbean Sea, about 135 million years ago. Thin dark, organic-matter-rich bands alternate with paler grey beds, forming a barcode-like pattern laid down by an ocean whose deeper waters were periodically starved of oxygen. These strata record one of the earliest major climate disturbances of the Cretaceous world: this has been called an Oceanic Anoxic Event or OAE.

In our recently published open-access article in Frontiers in Earth Science, we analyzed sediments from a quarry near the town of Pons, in the Sierra de los Órganos, to reconstruct how the early Proto-Caribbean responded when Earth’s carbon cycle shifted into a different state.
During the Valanginian (Early Cretaceous Period), greenhouse conditions were already in place, but something pushed the system further. Some scientists think in terms of volcanic outgassing, high CO₂, intensified weathering, and nutrient-rich runoff. The oceans stored this disturbance in the only way they can, by changing how they circulate, how they feed life, and how much oxygen reaches the depths. In many basins worldwide, that change shows up as intervals of dark, organic-rich sediments and a global shift in carbon isotopes. This coupled package of carbon-cycle disruption and marine deoxygenation is what we call the Weissert Event.

La Lata sits on what was then a marine slope along the margin of the young Proto-Caribbean Basin, between the evolving Americas and the Tethyan realm. Today it’s an active quarry. In the early Cretaceous it was a quiet pelagic seafloor, slowly accumulating the skeletal rain of coccolithophores, radiolarians, and tiny foraminifera. In that setting, any disturbance in oxygen, productivity, or sediment flux is recorded very efficiently.

We focused on just the lowermost ~4 meters of a ~30-meter section of the Pons Formation. At first glance it seems simple: comparatively thick, medium-gray limestones rich in carbonate are interbedded with much thinner, darker, carbonaceous marls and marly limestones. Under the microscope, however, this “barcode” resolves into five distinct microfacies, ranging from bioturbated, fossil-rich limestones to laminated, nearly barren, organic-rich levels with abundant sulphate minerals, like pyrite.

The first key result is how carbon cycle is distributed and sequestered within the sediments. The dark marls contain total organic carbon up to ~10-11 wt%, while the paler limestones usually sit around 1-3 wt%. Total inorganic carbon behaves in the opposite way: carbonate-rich in the thick gray beds, diluted where organic matter and clay concentrate. That alternation already hints at fluctuating conditions at the seafloor. These were intervals more favorable to the preservation of organic matter, separated by more “normal” background sedimentation.

Superimposed on that fabric is a clear negative excursion in δ¹³Corg of about 1.7‰. That excursion is not random in time. Biostratigraphic markers, especially the presence of specific calcareous nanoplankton place this interval in the late Valanginian subzone NK3B, the very window classically associated with the Weissert Event elsewhere in the world, and linking our local curve to the global record.

The dark beds do more than carry isotopes. They are loaded with mineral and microscopic evidence that oxygen in bottom waters dropped sharply during certain pulses. Under SEM we see framboidal pyrite and small cubic aggregates, often growing inside foraminiferal tests, mingled with illite-smectite clays and microbial fabrics. Redox-sensitive trace elements peak in the same horizons: vanadium, nickel, chromium, molybdenum, uranium, thallium, and sulfur all show marked enrichments where total organic carbon is highest. At the same levels, detrital indicators such as Al, Si, Ti, and Li also increase, suggesting stronger terrigenous flux -probably the fingerprint of enhanced runoff and weathering on land.

Bioturbation tells a complementary story. In the thick gray limestones, burrows are common and the bioturbation index often reaches 3–4: the seafloor was oxygenated enough for infauna to churn the sediment. In the organic-rich marls, the index drops to 1–2, and X-ray images reveal only faint, incomplete structures. These are intervals where oxygen availability was restricted enough to suppress most benthic activity.

Put together, the picture that emerges is not a single, monolithic “black shale” horizon but a series of deoxygenation pulses, closely tracking the negative carbon isotope excursion. During those pulses, Los Órganos lay beneath waters that were more stagnant or less ventilated, but more superficially nutrient-rich. Organic matter arriving at the seafloor was less efficiently destroyed, sediment input from land was boosted, and trace metals were scavenged from the water column into the accumulating muds.

Why does this matter beyond the satisfaction of matching a Cuban cliff to a named global event? First, it demonstrates that the Proto-Caribbean Seaway did not sit on the sidelines of Valanginian climate change. It participated fully in the Weissert disturbance. The same isotope signal, the same style of organic-rich sedimentation, and comparable redox signatures appear here as in better-known Tethyan sections. Second, the section at La Lata shows how a marginal to hemipelagic basin can register global forcing factors like higher CO₂, weathering, in its own local language of facies, microfossils, and chemical inventories.

Finally, there is an uncomfortable echo with the present. The rocks at La Lata, Sierra de los Órganos, formed under long-term CO₂ buildup, intensified weathering, and nutrient loading. The ocean responded by reorganizing circulation and oxygen distribution, carving “dead-zone” intervals into the sedimentary archive. Today we are driving the carbon cycle far faster, but the physics and chemistry of seawater have not changed. Ancient barcodes like those of the Pons Formation are not predictions, but warnings. When the carbon cycle is pushed hard, oceans everywhere, from open basins to narrow seaways, can slide toward deoxygenation affecting not just the carbon cycle, but all life in earth.

In that sense, each black band in the quarry is both a record of a vanished ocean and a quiet reminder that Earth’s climate system has thresholds. Our goal at La Lata was to read that record as clearly as possible, and to place the Proto-Caribbean firmly on the map of ocean anoxic event research. The story those limestones tell is simple and stark = when the planet breathes carbon too quickly, the oceans are often the first to lose their breath.

Recommended paper

Our pen-access article: Orihuela J., Melinte Dobrinescu M.C. and Maurrasse F.J-M.R. (2025) “Characterization of the Weissert oceanic anoxic event in lower Cretaceous limestones of the Guaniguanico terrain, Sierra de los Órganos, Western Cuba,” published in Frontiers in Earth Science (Vol. 13, 1549274) on 20 April 2025 (doi: 10.3389/feart.2025.1549274).

Jurassic Ferns from the Girón Group: A Window into Ancient Tropical Ecosystems

A new study published in the Journal of South American Earth Sciences opens a small window on the flora and environmental conditions of tropical South America during the Late Jurassic. 

The paper, "Jurassic fern Piazopteris from the Girón Group, Colombia: A taxonomic and paleoenvironmental evaluation," presents the discovery and analysis of six fossil fern specimens from the Eastern Cordillera of Colombia, helping expand a bit of knowledge of Jurassic plant life in the paleo-Caribbean region.

The fossils were collected from the carbonaceous mudstones of La Honda Creek, part of the Girón Group—an important but underexplored sedimentary unit that preserves traces of Mesozoic terrestrial ecosystems. The ferns are tentatively identified as Piazopteris cf. branneri, a member of the now-extinct genus of the Matoniaceae. Piazopteris once thrived in humid, equatorial climates.

What makes this study particularly compelling is its multidisciplinary approach. Using thin-section petrography, scanning electron microscopy (SEM), and carbon geochemistry—including total organic carbon (TOC) and stable isotope (δ¹³Corg) analyses—the researchers aproximated the depositional environment and climate context of these fossils. The results point to a low-energy, swamp-like setting with significant organic accumulation, likely influenced by a humid, tropical to subtropical climate. The geochemical data not only support this interpretation but also provide a valuable window into the carbon cycling and preservation conditions of Jurassic terrestrial environments.

The genus Piazopteris is a biostratigraphically and paleoecologically relevant genus, typically associated with Jurassic-Cretaceous floras of Gondwanan affinity. The occurrence of Piazopteris cf. branneri in Colombia contributes to a growing record of Jurassic ferns in South America and provides important taxonomic refinements for this group, which has often been misidentified or found poorly preserved.

Importantly, this work also underscores the scientific potential of the Girón Group as a paleobotanical archive. While the Girón Group has been recognized for its sedimentological and tectonic significance, its paleontological potential remains vastly underutilized. This new contribution highlights the need for further research, particularly stratigraphic refinement, paleobotanical and geochemical work in this region.

This study was carried out by a multidisciplinary team of geologists and paleontologists from several institutions in Colombia and abroad, including the Universidad Industrial de Santander (UIS), Florida International University (FIU), and research institutes focused on stratigraphy and paleontology. The collaboration brought together the fields of sedimentology, paleobotany, geochemistry, and microscopy to advance understanding of Jurassic floras in tropical settings. 

Special thanks go to all who helped make this discovery and research possible.

Citation:

Torres-Parada, J.M., Orihuela, J., Alarcón Gómez, C.M., Diaz Villamizar, J.S., Gómez-Coronado, J.S., Márquez-Prada, J.J., Lizarazo-Pabón, J.A., Patarroyo, G. (2025). Jurassic fern Piazopteris from the Girón Group, Colombia: A taxonomic and paleoenvironmental evaluation. Journal of South American Earth Sciences, 158, 105488. https://doi.org/10.1016/j.jsames.2025.105488

Images created with AI (ChatGPT Image creator, 2025). 

Ancient Sand Dollars Reveal a Lost Caribbean Ecosystem: New Findings from South-Central Cuba

The fossil record offers glimpses into ancient worlds, and a new study on Clypeaster echinoids from Cuba’s Damují Formation provides valuable insights into the Caribbean’s past. These fossils, dating from the Late Eocene to Early Oligocene, represent some of the earliest known occurrences of this genus in the region.

The research, conducted in Rodas, south-central Cuba, extends the known temporal and geographical range of Clypeaster, a genus of sand dollars that still thrives in tropical and subtropical oceans today. While previous studies focused on Oligocene and Miocene specimens, these newly examined fossils fill a gap in our understanding of how echinoids evolved and dispersed during a critical period of climatic transition—the Eocene-Oligocene boundary.

The geological context of the Damují Formation suggests that Clypeaster lived in a diverse marine environment, alongside large foraminifera, corals, and small fish. The presence of these fossils indicates that warm, shallow-water reef systems persisted in the Caribbean despite global cooling trends at the time. This challenges previous assumptions that echinoid diversification in the region occurred later, during the Miocene.

The study also raises intriguing questions about the role of the Caribbean as a migration corridor for marine life during the Paleogene. Were these Clypeaster populations early colonizers, or did they represent a more ancient lineage persisting through climatic shifts? Future research, including detailed morphological analyses and comparisons with other fossil sites, may help unravel the evolutionary pathways of these echinoids.

By documenting these fossils, this study contributes to our understanding of past ecosystems and the biogeographical history of echinoids. It also underscores the importance of Cuba’s fossil record in reconstructing ancient marine environments and refining our models of species distribution during critical periods of Earth’s history.

This work was made possible through the contributions of coauthors Carlos Rafael Borges-Sellén, Alberto F. Arano-Ruiz, Johanset Orihuela, and Yasmani Ceballos-Izquierdo, whose efforts in fieldwork, analysis, and writing were fundamental to this research. The full paper is available for download here.

The study is published in POEYANA, a peer-reviewed open-access journal (ISSN: 2410-7492, RNPS: 2403) that has been a cornerstone of zoological research in Cuba, the Caribbean, and the Neotropics since its founding in 1964. Originally established at the former Institute of Zoology of the Cuban Academy of Sciences, POEYANA is now edited by the Institute of Ecology and Systematics under the Ministry of Science, Technology, and Environment (CITMA). With over 500 published articles spanning more than five decades, the journal continues to serve as a platform for scientific contributions from Cuban and international researchers in the field of natural sciences.

Fossil News! First Pliocene Land Vertebrate Fossils from Cuba

I’m thrilled to announce the publication of our latest research paper, "First Record of Terrestrial Vertebrates from a Late Pliocene-Early Pleistocene Deposit in Cuba," which uncovers the first documented Pliocene land vertebrate fossils in Cuba’s history to date. Found at the El Abra outcrop in Matanzas, these fossils offer a rare glimpse into the prehistoric fauna of the Greater Antilles, hinting at unique evolutionary patterns and diversity, plus providing new insight into the biodiversity and biogeographic history of the Caribbean region.

While we recognize that possible land vertebrate fossils of older age may exist in the caves of Pinar del Río, these remain untested and are generally assumed to be Pleistocene, and even later in the Pleistocene, in age. As such, our findings from El Abra represent the earliest confirmed fossils within the Late Pliocene-Early Pleistocene range, adding a new dimension to our understanding of Caribbean vertebrate evolution.

One particularly exciting aspect of this discovery includes previously undocumented remains of capromyine rodents (so called hutias or jutias), showcasing unique dental characteristics that hint at possible connections with species in Hispaniola. This find challenges and enriches our understanding of Caribbean vertebrate dispersal and diversification, underscoring the importance of examining overlooked fossil records or outcrop deposits to piece together new evolutionary histories.

I am immensely grateful to my colleagues and co-authors Yasmani Ceballos, Lazaro Viñola, Logel Lorenzo and Alberto Clark, who collaborated on this project, contributing their expertise and dedication to each step of this investigation. Further thanks are due to the friends and institutions, for logistics, conversations, sharing of ideas, knowledge, and collecting permits. 

Take a look and join us in exploring this new chapter of Cuba's fossil record and its broader implications for Caribbean paleontology!

Source: 

Orihuela, J., Viñola-Lopez, L. W., Lorenzo, L., Clark, A., & Ceballos-Izquierdo, Y. (2024). First Record of Terrestrial Vertebrates from a Late Pliocene-Early Pleistocene deposit in Cuba. Journal of South American Earth Sciences, 105200.