Historical changes on coral reefs

Understanding the long-term dynamics of coral reef ecosystems helps place modern changes into historical context and reveal ecological processes. We build long-term records of ecosystem change on reefs by coring or bulk sampling fossil and modern coral reefs and extracting the skeletal remains of fishes, sponge spicules, algae, molluscs, urchins (and anything else that leaves a fossil record) and identify them using in-house reference collections. We use high resolution U-Th to date our samples, and stable isotope analyses to extract ecological and environmental information. These millennial-scale records provide pre-human baselines and reveal the timing of ecosystem changes. By disentangling the roles of natural and anthropogenic causes of shifts in reef states we hope to provide conservation targets and recommendations.

Fossil shark dandruff

Erin Dillon, PhD Candidate at UC Santa Barbara and STRI fellow is leading studies into reconstructing ancient shark communities using fossilised shark dermal denticles (skin teeth). Read more about her work here and grab Erin’s papers.

Formation of the Isthmus of Panamá

The formation of the Isthmus of Panama stands as one of the greatest natural events of the Cenozoic. It joined the two American continents and split an ocean in two, offering a unique natural experiment in ecology and evolution. Reconstructing how and when the Isthmus of Panama formed is therefore critical for understanding the evolution and biogeograhical history of life across the Americas. In this suite of papers we argue that formation of the land bridge took many millions of years, slowly constricting the seaways until the final land bridge was complete around 2.8 million years ago.

Paleoenvironmental changes

Reconstructing past environments provides essential context to any measures of ecological and evolutionary study. We use a variety of approaches including sediment analyses, stable isotopes and fossil morphometrics.

Recently, we have been trying to understand the causal mechanism(s) of the region-wide Plio-Pleistocene extinction in the Caribbean. Previous work found that extinctions lagged 1-2 Myr behind the apparent cause. Ethan Grossman led this study to reconstruct coastal Caribbean conditions using stable isotope profiling of gastropods. We found during the apparent extinction “lag”, large quantities of seasonal rainfall were affecting coastal communities. The timing of cessation of freshwater input coincides better with the extinctions suggesting a causal link, but more work relating the biotic and environmental data is required.
(Image: Takuro Kobashi).

Ancient DNA

We have recovered ancient DNA from coral reef cores extending several thousand years in Caribbean and Pacific Panama. Much of the material We are looking to explore the validity of this material for reconstructing communities that leave no fossil record and interpret changes in biodiverisity. The project is in collaboration with Matt Leray at STRI.

Human-driveN evolution in Wild populations

Does the long-term harvesting of the largest individuals in a population apply selection to evolve to reproduce at smaller size?

Both Caribbean conch (Strombus pugilis) and Pacific Cynoscion (sciaenid fishes) show evidence of reducing size at maturity following millennia of harvesting.

Alexis Sullivan is exploring the genetic basis of this decline in size in fossil, archeological and modern conch.

Ancient whale migrations

PhD candidate Larry Taylor and Seth Finnegan at UC Berkeley led this study into the use of oxygen isotopes in whale barnacles to track whale migrations.

Larry used fossil whale barnacles from Panama and other locations to show that Pacific humpback whales in the Pleistocene were undertaking migrations remarkably similar to those of modern whales.

Ecological History of the Panama canal

When the Panama Canal was built 100 years ago it formed Gatun Lake – at the time the largest man-made lake in the world. Little is known about how freshwater communities in the lake evolved in response to construction of the canal, flooding of the lake, subsequent natural climatic fluctuations, introduced species and eventually canal expansions.

Jorge Salgado is leading this project to unite sediment core records with environmental data to reveal key events in the history of the canal and apply these to recommendations for future management of the canal.

Martina and the bridge of time

Martina is utterly bored by school…

That is until she notices that her history book only starts with the arrival of Christopher Columbus in 1502. There must have been someone, something in Panama before then!

Frustrated by a lack of answers, Martina cobbles together a time machine to find out for herself. As she hurtles back through time, she begins to uncover the fascinating true history of the Isthmus of Panama – one of deep oceans, perilous volcanoes, long-extinct animals and complex human societies.

But time travel is trickier than she thought! When the time machine’s source of energy unexpectedly shatters, Martina gets trapped in the past. As she struggles to return home, Martina learns some unexpected truths about her own history – and herself

Join Martina in this coming-of-age time-travel quest with Panamanian artist Ian Cooke-Tapía and Smithsonian scientist Aaron O’Dea.

A history of life in 100 fossils

With Paul Taylor we showcase 100 key fossils that together illustrate the evolution of life on earth. We selected iconic specimens from collections at the Natural History Museum, London and Smithsonian Institution. Fossils were chosen not only for their importance in the history of life, but also because of the visual stories they tell.

So far, the book has been published in six languages (English, German, Japanese, Chinese, French and Italian) and is available all over.

Historia Natural del Istmo de Panama

Este libro, editado con Félix Rodríguez, reúne a investigadores de una amplia gama de disciplinas para presentar, en nueve capítulos, información sobre los ecosistemas, los cambios climáticos y la evolución de las faunas y floras marinas y terrestres en el istmo de Panamá.

El libro fue apoyado por SENACYT.