Félix Rodríguez-Mejia

• Professor
• Scientific Coordinator at Smithsonian Tropical Research Institute

Globally, efforts are being made to sustainably conserve and manage threatened ecosystems and the associated ecosystem services derived. However, evidence suggests that economic interests are increasingly being prioritized over the environment and the livelihoods of local resource-dependent communities. This review consists of four case studies fro...

Billfishes include some of the largest pelagic teleostean species, but several aspects about their morphology, paleobiology, and evolution remain ambiguous. Their fossil record is fragmentary and mostly represented by rostral and skull remains. Here, we present a comparative study of the caudal vertebral morphology of extant istiophorid species and...

A growing body of palaeoecological studies delineate long-term trends in the energetic structure of marine ecosystems, based primarily on the taxonomic and trophic composition and size-frequency distributions of local fossil assemblages. Changes in primary productivity are often invoked as drivers of these trends but the relationship between produc...

During the last 20 years of paleontological expeditions in different sedimentary basins of Brazil, Colombia, Costa Rica, Ecuador, Jamaica, Trinidad, Panama, the Dominican Republic and Venezuela, teleost otoliths have been found along the tropical western central Atlantic (TWCA) and the tropical eastern central Pacific (TECP); these otoliths relate...

The examined Ariidae marine catfish from the Neogene of tropical America consisted of isolated skulls, otoliths and bone fragments, some of which were described independently as otolith-based species or skull-based species. We used three-dimensional digital rendering (microCT) of skull and otolith reconstructions to recognize anatomical patterns in...

This study reports a three-dimensional fossil skull of a Tetraodontidae that dates to the middle Miocene (Serravallian), which was recovered from a rock matrix from the Valiente Peninsula Formation in the Bocas del Toro Archipelago, Panama. The new species, †Lagocephalus striatus n. sp., is the first fossil species of Tetraodontidae described from...

Fossil Diodontidae in Tropical America consist mostly of isolated and fused beak-like jawbones, and tooth plate batteries. These durophagous fishes are powerful shell-crushing predators on shallow water invertebrate faunas from Neogene tropical carbonate bottom, rocky reefs and surrounding flats. We use an ontogenetic series of high-resolution micr...

Examined specimens. (DOC)

Micro CT reconstruction of jaw from the extant species Diodon hystrix UFF ZO426. (AVI)

Micro CT reconstruction of jaw from the extant species Chilomycterus spinosus. UFF ZO314, 92 mm total body length, 72 mm standard length. (MOV)

Number of dental sheets in Diodon (circle) and Chilomycterus (triangle), as a function of the body size (standard length). Blue color: referential data from Tyler [91]; green color: Micro CT data from the present work. (TIF)

Micro CT reconstruction of fossil jaw from †Chilomycterus tyleri n. sp. NMB P1208. (AVI)

Micro CT reconstruction of jaw from the extant species Chilomycterus spinosus UFF ZO313. (AVI)

Micro CT reconstruction of jaw from the extant species Chilomycterus spinosus. UFF ZO315, 276 mm total body length, 230 mm standard length. (MOV)

Micro CT reconstruction of jaw from the extant species Chilomycterus spinosus. UFF ZO312, 159 mm total body length, 120 mm standard length. (MOV)

The Carcharodon carcharias is the largest living predatory fish, with a total length exceeding 6 meters. This shark appears during the early Pliocene, and currently has a cosmopolitan distribution, inhabiting mainly in coastal and offshore temperate environments, although some individuals have been referred to tropical waters. From North and South...

Caribbean reef corals have declined sharply since the 1980s, but the lack of prior baseline data has hindered identification of drivers of change. To assess anthropogenic change in reef environments over the past century, we tracked the composition of subfossil assemblages of bivalve and gastropod mollusks excavated from pits below lagoonal and off...

Historia natural del Istmo de Panamá ". Bajo esta premisa se redescubren las bellezas del paisaje panameño, muchas veces desapercibido por las tribulaciones del día a día. Es imperativo para las actuales y futuras generaciones de hombres y mujeres valorar nuestro entorno, conservarlo y protegerlo. Para ello, es necesario saber de dónde venimos y ha...

Intensive size-selective harvesting can drive evolution of sexual maturity at smaller body size. Conversely, prehistoric, low-intensity subsistence harvesting is not considered an effective agent of size-selective evolution. Uniting archaeological, palaeontological and contemporary material, we show that size at sexual maturity in the edible conch...

Nitrogen isotope ratios (15 N/ 14 N) as recorded in tissues and shells of modern bivalves have the potential to serve as a proxy for natural and anthropogenic nitrate fluxes in coastal environments. Nitrogen isotope ratios vary in coastal environments as a result of local productivity and nitrate source. Local productivity affects how much nitrate...

Caribbean coastal ecosystems have undergone severe degradation both historically and recently, primarily caused by the synergistic effects of overfishing, eutrophication, sedimentation, disease, and other factors associated with humans. Baseline conditions from pristine Caribbean reefs and seagrass beds are required to understand and quantify degra...

Today there is a tight-knit relationship between the elevation of the Central American Isthmus and the ocean-ographic conditions of the Tropical Eastern Pacific. Where the elevation drops below 500 m low-level wind jets pass seasonally from the Atlantic to the Pacific driving coastal upwelling in the Tropical Eastern Pacific. This paper determines...

Environmental response in the Pacific to aseismic Cocos Ridge subduction (Panama and Costa Rica). The evolution of the marine communities along the Pacific coast of Central America, may have changed in response to the formation of the Isthmus of Panama. To evaluate the effect of the Aseismic Cocos Ridge (DAC) subduction on the marine benthic commun...

Colonial invertebrates often mix sexual and asexual methods of propagation, and a comprehensive understanding of both is required for life history study. The asexual cloning of new colonies in cupuladriid bryozoans is much better studied than the formation of new colonies by sexual reproduction. As such, the relative investments of sexual and asexu...

Numerous gross morphological attributes are shared among unrelated free-living bryozoans revealing convergent evolution associated with functional demands of living on soft sediments. Here, we show that the reproductive structures across free-living groups evolved convergently. The most prominent convergent traits are the collective reduction of ex...

  Cupuladriid cheilostome bryozoans can make new colonies both sexually and asexually. Sexual (aclonal) colonies are derived from larvae while asexual (clonal) colonies result from the fragmentation or division of larger colonies. A number of specialised morphologies exist which either enhance or discourage clonality, and cupuladriids preserve thes...

We investigate the effect of the temperature–size rule upon zooids of the tropical American bryozoan Cupuladria exfragminis. Results show that mean zooid length, zooid width and zooid area vary significantly between clonal replicates of C. exfragminis kept under different controlled temperature conditions. Significantly larger zooids are produced d...

The Isthmus of Panama contains an extremely rich fossil record that has enabled paleontologists to assemble a fascinating account of how the Isthmus formed, and what the environmental, ecological and evolutionary consequences of its formation were to life in the seas of Tropical America. In this paper we celebrate 20 years of the Panama Paleontolog...