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Malcolm Hill's Lab

Our research is focused on the evolutionary ecology of species interactions in tropical and temperate marine environments. We work on a diversity of questions, most of which use sponges as model organisms, and our work takes place in the field (snorkeling and diving) and in the lab (DNA-based molecular work). One major area of exploration is symbiosis between sponges and their microflora. We are interested in factors that influence the structure, stability, and genesis of symbiosis between sponge hosts and zooxanthellae (for the tropical sponges) and bacteria (for tropical and temperate sponge). Our work in this area has been supported by the NSF, and includes an examination of the impact rising seawater temperatures will have on sponge:zooxanthellar symbioses and the microflora harbored by Chesapeake Bay sponges. We are exploring the diversity of zooxanthellae harbored by sponges, the role the zooxanthellae play in host performance, and the evolutionary and ecological forces that shape these symbioses. We also do work on the role that sponges play in ecological communities in marine habitats. We’ve studied the effects predators have on sponges in population and communities contexts (e.g., sponge anti-predator adaptations (structural and chemical), novel pigment production by sponges and their symbionts, sponge:coral competition, phenotypic plasticity in sponges). Collaboration is a key element to all of the work we do, and we work with all types of scientists. We have several on-going projects with Dr. April Hill to study the genetic control of sponge developmental in an evolutionary context. Sponges provide a unique system to explore hypotheses about the early animal evolution and the transition to multicellularity. Working with a large number of labs from the US and abroad, we recently initiated a project to generate a well-supported molecular and morphological phylogeny of the sponges. This 5-year, NSF-supported, international collaboration is know as the  Porifera Tree of Life (PorToL) project.

Current Projects

  • How many different types of zooxanthellae occupy sponge hosts, and what are the ecological and evolutionary consequences of that symbiont diversity? Are sponge symbionts providing adaptive benefits to their hosts?
  • What factors drive organisms towards symbiotic interactions, and how are the interactions among partners regulated (e.g., genetically, morphologically)?
  • How will sponge symbioses respond to environmental change?
  • What ecological role do sponges play in the habitats they live in?
  • What insights into early animal evolution will we gain through a well-supported sponge phylogeny?

Current Lab Members

Sarah Friday '13
Tyler Heist '15
Molly Meypans '15
Shirley Chu '15
Garrett Fundakowski '16
Marissa Parker '16