Scolecophidians ("blind snakes") are burrowing snakes that feed primarily on small, social insects such as ants, termites, and their larvae. They include the smallest snakes and are distributed on all continents except Antarctica, primarily in tropical and subtropical regions. Due to their fossorial lifestyle, they are among the most poorly-known major groups of vertebrates. Studies have suggested that scolecophidian species diversity is greatly underestimated because the morphological differences separating species are fewer than usual and harder to detect with conventional methods. This project investigates the relationships of populations and species of scolecophidians using DNA sequences and phylogenetic methods, in order to better understand hidden species diversity within the group and how species became distributed throughout their range.
This project confers significant benefits for biodiversity and conservation efforts by revealing a large component of hidden diversity within tropical vertebrates. The small distributions of most species, combined with their declining forest habitats, place them among the key indicators of environmental health. A better understanding of species boundaries and relationships also makes these organisms more accessible for study to other biologists, such as ecologists, physiologists, and conservation biologists. The project involves both field and laboratory training of graduate and undergraduate students.
The blindsnakes (scolecophidians) are the most poorly known of all snakes in terms of number of species, relationships, distribution, and how they live (ecology). They are burrowing reptiles that feed primarily on small, social insects such as ants, termites, and their larvae. They include the smallest snakes and they rarely exceed 30 centimeters (12 inches) in length. Most species resemble earth worms and have small eyes and a pinkish or brownish, tubular-shaped body with smooth scales. Blindsnakes are distributed on all continents except Antarctica, and occur in the United States. The two major groups of blindsnakes are the threadsnakes (leptotyphlopids), which are very thin and occur mainly in South America and Africa, and the typical blindsnakes (typhlopoids), which occur there and on other continents. A third group (anomalepidids) occurs in Central and South America. It is known from fossils and molecular evidence that scolecophidians are also the oldest snakes, most likely to have been influenced by continental drift in their history. Ecologically, they are an important part of the soil community in many areas around the world. This project involved a team of researchers assembled to investigate the relationships of these organisms with molecular data, to improve their classification and better understand their biogeographic history. This was accomplished in a series of studies that were conducted and published. They learned that the geologic separation of Africa and South America isolated the threadsnakes on those two continents, influencing their later relationships. Subsequently, threadsnakes reached North America and Caribbean islands by dispersal from South America. In a separate study on typical blindsnakes, these researchers found that continental drift also had a major impact on their historical biogeography and relationships. Snakes now occurring in India and Madagascar diverged from one another at the time when those two land masses split apart in the geologic past. The later history of typical blindsnakes was further influenced by continental drift, dispersal, and the radiation of social insects. As a result of this work, the classifications of these snakes were revised and many unrecognized species were discovered. This project involved undergraduate and graduate students, as well as collaborators from three other continents. The results now raise awareness of the importance of these animals that were otherwise poorly known, and the revised classifications are being used agencies charged with managing and protecting the environment, and by educators and other researchers.
