My primary research interests lie in evolutionary biology, which is fundamental to understanding the processes that form and maintain biodiversity. I am particularly interested in the study of highly diverse ecosystems and how they are molded through processes like speciation and adaptive radiation. I use spiders and other arachnids as models to address these issues in my research. My research to date combines these cross-disciplinary interests, using an integrative approach to answer questions of interest. The unifying theme concerns the formulation of evolutionary conclusions using morphology, genes and behavioral studies. I use taxonomy, molecular biology, phylogenetics, and field ecology to build a comprehensive understanding of the evolutionary processes involved in the formation of biodiversity.
If you are interested in joining our lab as a graduate student, please contact Suresh Benjamin (firstname.lastname@example.org). Mention why you want to join our lab and attach your CV. All NIFS funded prospective graduate students have to apply through the director, when openings are advertised here. However, it is helpful for us to know that you are specifically interested in joining our lab.
1. Endemics of the central highland of Sri Lanka
Tropical mountains have exceptionally high numbers of endemic species. The central highlands of Sri Lanka are no exception. Many species are endemic to single mountain peaks; most are still unknown to science. They are also critically endangered due the changing climate. We are currently exploring these mountains for spider to understand their evolutionary history. Another line of investigation is to understand the molecular basis of endemism.
Mphil Students: Ms. Nilani Kanesharatnam and Ms. Dilini Bopearachchi Funding: NRC
2. Evolution of the jumping spiders (Salticidae)
Jumping spiders are small, diurnal hunters remarkable for their excellent vision, various body forms and behaviours. They are known from all non-polar terrestrial ecosystems. With more than 6053 species described in 632 genera jumping spiders are largest spider family. However, their above genus level phylogenetic relationships are not well understood. This project aims to place the island salticids in a phylogenetic context and thereby better understand the evolutionary history of the family.Mphil Students: Ms. Nilani Kanesharatnam and Ms. Dilini Bopearachchi
Funding: NIFS, NSF, NRC
3. Higher level phylogeny and evolution of the crab spiders (Thomisidae)
Members of the Family Thomisidae Sundevall, 1833 are universally known as crab spiders because of their crab-like, laterigrade leg orientation. They are cryptic dwellers of habitats ranging from foliage, flowers, tree bark and leaf litter. Thomisidae is the seventh largest family of spiders and currently includes 2171 species placed in 170 genera. The National red list of Sri Lanka (2012) list 36 nominal species of crab spiders for the island. However, most of what we know of their biodiversity is from their historic initial descriptions. The taxonomy and phylogenetic position of Sri Lankan crab spiders has been the center of focus in an ongoing island wide survey of spider diversity
4. The phylogenetics of hybrids between the Sri Lankan primate species of langur (Semnopithecus priam thersites and S. vetulus)
The last 50 years of primate studies at Polonnaruwa (e.g., Dittus, 2013) have uncovered 36 cases of hybrids between the Gray or Hanuman langur (Semnopithecus priam thersites) and the Purple-faced langur (Semnopithecus vetulus philbricki). The behavioral, demographic and ecological events surrounding these hybridizations have been well documented. The focus here is a new initiative, namely to investigate the genetic consequences and underpinnings of the hybridization events among Sri Lankan langurs. The genetic profiles of the Sri Lankan langur populations will give us new insights into the phylogeny of these populations and the behavioral, ecological and demographic roles in their evolution. It will expand our understanding of the biogeography of Sri Lankan mammals, evolution of primate taxa in general and specifically in the South Asian region.
Project Head: Wolfgang Dittus; collaborators: Suresh P. Benjamin & Praveen Karanth; students: Nirmal Rathnasiri.
5. Screening mammal biodiversity using DNA from leeches
Project Head: Suresh P. Benjamin; students: Nirmal Rathnasiri, Ms. Rachitha Vitharana
Contact email: Suresh.Benjamin@gmail.com
Mr. N. P. Athukorala