Publication Search Results

ID: 154319
Type: article
Authors: Aguilera, Orangel; Oliveira de Araújo, Olga M.; Hendy, Austin; Nogueira, Anna A. E.; Nogueira, Afonso C. R.; Wagner Maurity, Clovis; Tavares Kutter, Vinicius; Alves Martins, Maria Virginia; Coletti, Giovanni; Borba Dias, Bruna; Silva-Caminha, Silane; Jaramillo, Carlos; Bencomo, Karen; Lopes, Ricardo Tadeu
Keywords: STRI

ID: 156400
Type: article
Authors: Barreda, Viviana D.; Zamaloa, María del Carmen; Gandolfo, María A.; Jaramillo, Carlos; Wilf, Peter
Keywords: STRI

ID: 157254
Type: article
Authors: Benites-Palomino, Aldo; Aguirre-Fernandez, Gabriel; Moreno-Bernal, Jorge W.; Vanegas, Andres; Jaramillo, Carlos
Keywords: STRI
Abstract: The two extant genera of strictly freshwater dolphinsIniaandPlatanistaare the result of convergent evolution to freshwater environments with reduced visibility. Characterized by their long snout and small melon, these extant taxa are clustered into two clades, Iniidae in South America and Platanistidae in Southern Asia. Their evolutionary history leading to freshwater environments remains mostly unknown, because many of their related fossil species have been found in marine environments. Here, we report riverine dolphin remains (two rostral fragments and a periotic) from two stratigraphic levels of the late middle Miocene (ca. 12.5 Ma) from La Venta, Colombia. The periotic has a reduced cochlear aqueduct mediodorsally oriented, the anterior process is relatively thin, and the dorsal opening of the facial canal is located lateral to the spiral cribriform tract. The rostral fragments are dorsoventrally flattened; the mandible features two longitudinal ventral grooves, and the premaxilla-maxilla suture of the rostrum is located in a deep lateral groove. These characteristics indicate that the specimens belong to Platanistidae, the lineage of the Ganges river dolphinPlatanista. Platanistids had also been recorded on coeval strata from the Fitzcarrald arch, Peru. The occurrence of middle Miocene platanistids in both the La Venta and Fiztcarrald localities suggests that members of this lineage moved into freshwater environments in South America earlier than the ancestors of the modern Amazon river dolphinInia. The subsequent collapse of the Pebas ecosystem could have played a role in the extinction of non-marine Platanistoidea in South America.

ID: 154852
Type: article
Authors: Cadena, Edwin-Alberto; Vanegas, Andrés; Jaramillo, Carlos; Cottle, John M.; Johnson, Thomas A.
Keywords: STRI
Abstract: Mesoclemmys is the most diverse extant genus of South American pleurodires or side-necked turtles, with at least 10 species inhabiting fluvial to littoral environments. Despite this high extant diversity and extensive geographic distribution, the evolutionary history and fossil record of this genus are completely unknown. Here, we describe the first fossil record of this genus, which supports a previous molecular-based hypothesis that indicates a minimum split time of 13.5 Ma between this and other genera of South American chelids. Mesoclemmys vanegasorum, sp. nov., is represented by a nearly complete shell (carapace and plastron) and some postcranial bones found in the middle Miocene (13.6 ± 0.2 Ma), La Victoria Formation, Tatacoa Desert, Colombia, increasing the turtle paleodiversity of La Venta Fauna. It differs from all extant species of Mesoclemmys by vertebral scute 1 reaching the sutural boundary between peripherals 1 and 2; shorter cervical and marginal scutes 1 to 3; pleurals 1 very advanced over the peripherals; pygal bone with a posteromedial shallow notch; vertebral 5 covering half of the pygal bone; small extragulars reaching only half of the epiplastra length; and a fine microvermiculation of the shell. Our phylogenetic results show a close relationship between M. vanegasorum, sp. nov., and the extant M. hogei. The overall morphology and size of Mesoclemmys genus have remained relatively constant for at least the last 13.6 million years. However, its geographic distribution has decreased drastically in northwestern South America, being restricted today to the lower region of the Magdalena River Basin.

ID: 157163
Type: article
Authors: Carrillo, Juan D.; Faurby, Søren; Silvestro, Daniele; Zizka, Alexander; Jaramillo, Carlos; Bacon, Christine D.; Antonelli, Alexandre
Keywords: STRI
Abstract: The biological interchange between North and South America associated with the formation of the Isthmus of Panama is key to defining current gradients of species diversity. A major gap in our understanding of the interchange is its asymmetry, where mammals of North American origin attained higher diversity in South America than vice versa. The prevailing view is that this asymmetry resulted from higher origination of immigrant mammals in South America. In contrast, we find that asymmetry results from high extinction of native mammals in South America, which reduced the diversity of native mammals available to disperse northwards. These results shed light on the legacy of the biotic interchange to understand the current patterns of species diversity across the Americas.The interchange between the previously disconnected faunas of North and South America was a massive experiment in biological invasion. A major gap in our understanding of this invasion is why there was a drastic increase in the proportion of mammals of North American origin found in South America. Four nonmutually exclusive mechanisms may explain this asymmetry: 1) Higher dispersal rate of North American mammals toward the south, 2) higher origination of North American immigrants in South America, 3) higher extinction of mammals with South American origin, and 4) similar dispersal rate but a larger pool of native taxa in North versus South America. We test among these mechanisms by analyzing ∼20,000 fossil occurrences with Bayesian methods to infer dispersal and diversification rates and taxonomic selectivity of immigrants. We find no differences in the dispersal and origination rates of immigrants. In contrast, native South American mammals show higher extinction. We also find that two clades with North American origin (Carnivora and Artiodactyla) had significantly more immigrants in South America than other clades. Altogether, the asymmetry of the interchange was not due to higher origination of immigrants in South America as previously suggested, but resulted from higher extinction of native taxa in southern South America. These results from one of the greatest biological invasions highlight how biogeographic processes and biotic interactions can shape continental diversity.Datasets and code have been deposited in Zenodo (https://doi.org/10.5281/zenodo.3770347) (74).

ID: 156865
Type: article
Authors: Martínez, Camila; Jaramillo, Carlos; Correa-Metrío, Alexander; Crepet, William; Moreno-Patino, Jorge Enrique; Aliaga, A.; Moreno, Federico; Ibañez-Mejia, Mauricio; Bush, Mark B.
Keywords: STRI
Abstract: Andean uplift played a fundamental role in shaping South American climate and species distribution, but the relationship between the rise of the Andes, plant composition, and local climatic evolution is poorly known. We investigated the fossil record (pollen, leaves, and wood) from the Neogene of the Central Andean Plateau and documented the earliest evidence of a puna-like ecosystem in the Pliocene and a montane ecosystem without modern analogs in the Miocene. In contrast to regional climate model simulations, our climate inferences based on fossil data suggest wetter than modern precipitation conditions during the Pliocene, when the area was near modern elevations, and even wetter conditions during the Miocene, when the cordillera was around ~1700 meters above sea level. Our empirical data highlight the importance of the plant fossil record in studying past, present, and future climates and underscore the dynamic nature of high elevation ecosystems.

ID: 156754
Type: article
Authors: Pimiento, Catalina; Bacon, Christine D.; Silvestro, Daniele; Hendy, Austin; Jaramillo, Carlos; Zizka, Alexander; Meyer, Xavier; Antonelli, Alexandre
Keywords: STRI
Abstract: The extinction of species can destabilize ecological processes. A way to assess the ecological consequences of species loss is by examining changes in functional diversity. The preservation of functional diversity depends on the range of ecological roles performed by species, or functional richness, and the number of species per role, or functional redundancy. However, current knowledge is based on short timescales and an understanding of how functional diversity responds to long-term biodiversity dynamics has been limited by the availability of deep-time, trait-based data. Here, we compile an exceptional trait dataset of fossil molluscs from a 23-million-year interval in the Caribbean Sea (34 011 records, 4422 species) and develop a novel Bayesian model of multi-trait-dependent diversification to reconstruct mollusc (i) diversity dynamics, (ii) changes in functional diversity, and (iii) extinction selectivity over the last 23 Myr. Our results identify high diversification between 23–5 Mya, leading to increases in both functional richness and redundancy. Conversely, over the last three million years, a period of high extinction rates resulted in the loss of 49% of species but only 3% of functional richness. Extinction rates were significantly higher in small, functionally redundant species suggesting that competition mediated the response of species to environmental change. Taken together, our results identify long-term diversification and selective extinction against redundant species that allowed functional diversity to grow over time, ultimately buffering the ecological functions of biological communities against extinction.

ID: 155487
Type: article
Authors: Scholz, Serena R.; Petersen, Sierra V.; Escobar, Jaime; Jaramillo, Carlos; Hendy, Austin J. W.; Allmon, Warren D.; Curtis, Jason H.; Anderson, Brendan M.; Hoyos, Natalia; Restrepo, Juan C.; Perez, Nicolas
Keywords: STRI

ID: 152068
Type: article
Authors: Cortés, Dirley; De Gracia, Carlos; Carrillo-Briceño, Jorge D.; Aguirre-Fernández, Gabriel; Jaramillo, Carlos; Benites-Palomino, Aldo; Atencio-Araúz, Joaquín Enrique
Keywords: STRI

ID: 146505
Type: article
Authors: D'Apolito, Carlos; Silva-Caminha, Silane; Jaramillo, Carlos; Dino, Rodolfo; Soares, Emílio A. A.
Keywords: STRI
Abstract: Palynological studies in central Amazonia are scarce, especially those concerned with resolving the age of sedimentary deposits. A recent opportunity allowed the stratigraphical and palynological study of a sedimentary unit below the Negro River's current channel. Age was constrained by the basal occurrence of Alnipollenites verus, and the top occurrence of Grimsdalea magnaclavata and Paleosantalaceaepites cingulatus, as late Pliocene to early Pleistocene. Here, we provide additional details on the palynostratigraphy and biodiversity of this deposit. Samples yielded 95 palynomorphs that included 58 pollen and 26 spore species, of which we identified botanical affinities with 26 angiosperm, one gymnosperm and four pteridophyte families. Twenty-five new taxa are erected, from which we recognise five angiosperm genera, namely Pacourina/Vernonia (Asteraceae), Myrsine? (Myrsinaceae), Symmeria (Polygonaceae), Faramea (Rubiaceae) and Schefflera (Araliaceae), plus a possible Marcgraviaceae pollen. These taxa, along with the majority of the recovered assemblage, are indicative of Amazonian lowland floras.

ID: 151803
Type: article
Authors: Fontes, Daiana; Jaramillo, Carlos; Moreno, Jorge Enrique
Keywords: STRI
Abstract: Amacayacu Forest Dynamics Plot (AFDP) is a 25-ha (500 m × 500 m) site located at Amacayacu National Natural Park (ANNP), Colombian Amazonia. The flora of AFDP is represented by terra firme Forest, the phytophysiognomic unit of the Amazon region with the greatest richness of plant species. However, high-resolution pollen images and morphological descriptions from the Amazon North-west are still rare. This study presents detailed information about pollen grains that will benefit future palynological analyses, particularly of Quaternary material. Herein we describe 255 tree species, comprising 72 families and 192 genera. Those species were grouped into 236 morphotypes. Six species revealed morphological variations among the pollen types within the same species and 36 species were impossible to differentiate from each other. Overall morphology shows apertures with a dominance of tricolporate (61%), inaperturate (5.8%), monocolpate (5.5%), and triporate (4.7%), and variation of sexine sculptures, with dominance of reticulate (66%), scabrate (11.3%), echinate (7.05%) and rugulate (4.3%). With respect to size, the equatorial diameter has a median of 29 µm (SD = 15.5), while the polar diameter has median of 32 µm (SD = 14.7).

ID: 154318
Type: article
Authors: Gomes, Bianca Tacoronte; Absy, Maria Lúcia; D'Apolito, Carlos; Jaramillo, Carlos; Almeida, Ronaldo
Keywords: STRI
Abstract: Western Amazonia underwent dramatic changes in its landscape and environments during the Neogene, which led to its extant, hyperdiverse, tropical rainforest. Although the palynological fossil record has been the most useful proxy for understanding the history of the Amazonian biome, the floristic composition and diversity of the Neogene and the present Amazonian environments have never been thoroughly compared. In this work, we present preliminary comparisons of the pollen content of a Miocene core from the Solimões Formation in western Amazonia (Brazil) with the pollen content of Holocene sediments from flooded environments (várzeas and lake margins) near the Miocene site. We found a total of 463 pollen and spore types (Miocene, n = 284; Holocene, n = 231), only 52 of which were shared. The Holocene flooding environments displayed distinct palynological signals; both the Holocene and Miocene palynofloras have pollen primarily sourced from the local, flooded environments, with no significant differences in within-sample pollen diversity. The Holocene palynoflora was more heterogeneous in composition than the Miocene palynoflora, probably because the Miocene wetlands (the Pebas System) were highly homogeneous at a continental scale, far more than modern western Amazonia, thus implying that the spatial vegetation turnover was much lower than in modern ecosystems.

ID: 152377
Type: article
Authors: Graham, Heather V.; Herrera, Fabiany; Jaramillo, Carlos; Wing, Scott L.; Freeman, Katherine H.
Keywords: STRI

ID: 151473
Type: article
Authors: Herrera, Fabiany; Carvalho, Mó; Jaramillo, Carlos; Manchester, Steven R.
Keywords: STRI
Abstract: Premise of research. Recent classifications of Anacardiaceae recognize two subfamilies, Anacardioideae and Spondioideae. Most genera within Spondioideae are still recognized for having drupes with sclerified stones that vary in locule number and germination mechanisms. Spondioid fruits have been recognized in the Cenozoic fossil record of Europe, Asia, and North America. However, they have remained elusive in the Neotropics, where today they are an important component of tropical rain forests and seasonally dry tropical forests. Here, we describe three new species of fossil endocarps related to Spondias, Dracontomelon, and Antrocaryon.Methodology. Fossil endocarps were collected from the 19–18.5 Ma (early Miocene) Cucaracha Formation, Panama Canal. The fossils were studied by physical sections, acetate peels, and X-ray microtomography. The fossil endocarps were exhaustively compared with all extant genera of Spondioideae.Pivotal results. Spondias rothwellii sp. nov. and Antrocaryon panamaensis sp. nov. are so far the earliest and best evidence of these genera in the Neotropics. Dracontomelon montesii sp. nov. extends the occurrence of this genus to the early Miocene in Central America.Conclusions. The new Cucaracha fossils reveal that Spondioideae were a significant part of the early Miocene forests in Panama. The extant natural habitats and occurrences of the newly recognized genera suggest multistratified rain forests and active biogeographical patterns for Spondioideae approximately 19 million years ago in southern Central America.

ID: 152642
Type: article
Authors: Herrera, Fabiany; Carvalho, Mónica; Wing, Scott L.; Jaramillo, Carlos; Herendeen, Patrick S.
Keywords: STRI
Abstract: Leguminosae are one of the most diverse flowering-plant groups today, but the evolutionary history of the family remains obscure because of the scarce early fossil record, particularly from lowland tropics. Here, we report ~500 compression or impression specimens with distinctive legume features collected from the Cerrejón and Bogotá Formations, Middle to Late Paleocene of Colombia. The specimens were segregated into eight fruit and six leaf morphotypes. Two bipinnate leaf morphotypes are confidently placed in the Caesalpinioideae and are the earliest record of this subfamily. Two of the fruit morphotypes are placed in the Detarioideae and Dialioideae. All other fruit and leaf morphotypes show similarities with more than one subfamily or their affinities remain uncertain. The abundant fossil fruits and leaves described here show that Leguminosae was the most important component of the earliest rainforests in northern South America c. 60–58 million years ago.

ID: 151387
Type: article
Authors: Luque, Javier; Feldmann, R. M.; Vernygora, O.; Schweitzer, C. E.; Cameron, C. B.; Kerr, K. A.; Vega, F. J.; Duque, A.; Strange, M.; Palmer, A. R.; Jaramillo, C.
Keywords: STRI
Abstract: Evolutionary origins of novel forms are often obscure because early and transitional fossils tend to be rare, poorly preserved, or lack proper phylogenetic contexts. We describe a new, exceptionally preserved enigmatic crab from the mid-Cretaceous of Colombia and the United States, whose completeness illuminates the early disparity of the group and the origins of novel forms. Its large and unprotected compound eyes, small fusiform body, and leg-like mouthparts suggest larval trait retention into adulthood via heterochronic development (pedomorphosis), while its large oar-like legs represent the earliest known adaptations in crabs for active swimming. Our phylogenetic analyses, including representatives of all major lineages of fossil and extant crabs, challenge conventional views of their evolution by revealing multiple convergent losses of a typical "crab-like" body plan since the Early Cretaceous. These parallel morphological transformations may be associated with repeated invasions of novel environments, including the pelagic/necto-benthic zone in this pedomorphic chimera crab.

ID: 153438
Type: article
Authors: Pérez-Escobar, Oscar Alejandro; Lucas, Eve; Jaramillo, Carlos; Monro, Alexandre; Morris, Sarah K.; Bogarín, Diego; Greer, Deborah; Dodsworth, Steven; Aguilar-Cano, Jos; Sanchez Meseguer, Andrea; Antonelli, Alexandre
Keywords: STRI
Abstract: Extremely high levels of plant diversity in the American tropics are derived from multiple interactions between biotic and abiotic factors. Studies have focused on macro-evolutionary dynamics of the Tropical Andes, Amazonia and Brazil's Cerrado and Atlantic forests during the last decade. Yet, other equally important Neotropical biodiversity hotspots have been severely neglected. This is particularly true for the Chocó region on the north-western coast of South and Central America. This geologically complex region is Earth's fifth most biodiverse hotspot, hosting approximately 3% of the global plant species. Here, we test Gentry's 1982a] proposal of a northern Andean-Central American Pleistocene origin of the Chocoan flora using phylogenetic reconstructions of representative orchid lineages in the American tropics. We show that orchids in the Chocó are derived mostly from Andean migrants. Contributions from distant biogeographical areas also exist but are fewer. We also identify a strong floristic connection between the Chocó and Central America, revealed by multiple migrations towards the Chocó during the last 5 million years. The dated phylogenetic reconstructions suggest a Pleistocene onset of the Chocó flora. Taken together, results support Gentry's assumption of a Pleistocene origin, compound assembly of the Chocoan biodiversity hotspot. Strong Central American-Chocoan floristic affinity may be partly explained by the accretion to north-western South America of a land mass derived from the Caribbean plate. Additional densely sampled phylogenies of prominent Chocoan lineages also well represented across the Neotropics could enlighten the role of land mass migrations through time in the assembly of floras in biodiversity hotspots.