Giant turtles all the way down
Nov08

Giant turtles all the way down

A Colombian coal mine opens a treasure chest of fossils. By Liza Lester IT was large, that much was obvious. When Edwin Cadena first saw the fossil in 2005, he thought he might be uncovering another specimen of Titanoboa cerrejonensis, the ancient snake he and his colleagues discovered in 2004 on a Smithsonian expedition lead by Carlos Jaramillo, Jason Head, and Jonathan Bloch. But as he slowly picked the rock away, the fossil was revealed as another giant reptile, a ~58-million-year-old contemporary of Titanoboa, and one of the largest freshwater turtles ever found. So big, even the 13-meter, two ton snake probably couldn’t swallow it. He named it Carbonemys cofrinii, “coal turtle.” Cadena, now a doctoral student with Dan Ksepka at NC State, found his turtle in the La Puente cut in the north zone of Colombia’s Cerrejón mine, one of the largest open-pit coal mines in the world. La Puente is an expanse of naked mudstone, stripped of jungle and a layer of coal. Hot, windy, and full of bones, with distant methane fires blooming off and on from an active face, it looks apocalyptic in photos. It is a treasure chest of fossils. View Larger Map We have few fossils from the tropics, where ancient remains lie deep buried under living jungle and tons of soil. It is rare that natural erosion reveals the secrets of the ancient tropics. The coal mine has peeled back the surface for the paleontologists, gratis. Candena has an awareness of his a time-table. Fossil excavation is slow work. He has only a few years to finish projects in progress before active mining resumes. How did the snakes and turtles get so large? Cadena thinks habitat and ecological interactions drove the gigantism. In addition to giant reptiles, the mine has uncovered the ancient jungle they in lived in, a wealth of plant fossils as important to understanding ancient ecosystems as the exciting megafauna. The fossil plant world is surprisingly familiar. The team has seen precursors of the living jungle, including modern bean, banana, and chocolate plants. Climate change may also have been a factor. Based on the great size of Titanoboa, Head et al concluded that the mean annual temperature of equatorial South America must have been warmer, in the range of 30–34 °C, consistent with controversial hot Palaeogene climate models. It seems the Colombia of the Palaeocene neotropics was not that unlike today, only more so – hotter, wetter, bigger. Cadena, E., Ksepka, D., Jaramillo, C., & Bloch, J. (2012). New pelomedusoid turtles from the late Palaeocene Cerrejón Formation of Colombia and their implications for phylogeny and body size evolution Journal of...

Read More

Saliva from moth larva increases potato crop yields in Colombia

Many farmers throughout Latin America and around the world rely on pesticides to control pest invasions; in the case of Andean potato crops, this method is not only costly but has been shown to cause adverse health effects as well. Due to the risks involved in pesticide usage, and the ever-increasing demand for high-yield crops, new methods of controlling pest invasions are being explored by researchers regularly. And as counterintuitive as these new findings sound, ecological scientists have discovered that, in the case of Colombian potato farms in the Andes, the pests themselves could actually increase productivity.

Read More

From the Community: Biodiversity in urban, isolated, marine and ancient settings

Millions of microbes found buried under the seafloor, fossils reveal the life of giant cockroaches and marine invertebrate struggles, a rare bird haven is explored in Colombia and urban ecologists address pollination in Harlem. Here’s the latest ecological news for the second week in April.

Read More

So you want to be a conservationist? Think of the community

When we consider all the conservation challenges facing our world and society, we know that communicating effectively to the community is not only helpful but necessary. However, many inspiring projects in various conservation areas have failed to succeed—not because the scientific background was not there or because the financial resources were unavailable—but because the community’s support was not entirely there. One of the elements to a successful conservation project is a strong connection to the community, especially during the early stages of project planning.

Read More