Home

 

 

 
Halanych Lab Projects

 
 
  • Animal Phylogeny
    One of the primary lines of research in the lab is to understand the evolutionary relationships among major animal lineages. This work is drawing on information from several different sources to build a comprehensive, consensus understanding of animal phylogeny. In particular, we are focusing on the Lophotrochozoan clade. This is a clade of bilaterian animals that is defined to be all the descendants of, and including, the last common ancestor of the annelids, mollusks, and the three lophophorate taxa (Brachiopoda, Phoronida, and Bryozoa). The term Lophotrochozoa refers to the fact that this lineage includes the traditional Lophophorate groups and lineages with trochophore larvae (sensu lato).
  • Icy Inverts: Evolution of Antarctic Invertebrates
    The overarching goal of our studies in Antarctica is to develop an evolutionary understanding of how marine benthos have been influenced by the geological and evolutionary history in the Southern Ocean. Specifically, we are interested in how organisms can maintain genetic continuity (i.e., non-endemics) across the Drake passage, despite the presence of the strong anti-cyclonic current that forms the sub-Antarctic and Antarctic polar front. We are also interested in genetic connectivity or structure throughout Antarctic waters. To explore the genetic continuity among marine invertebrate taxa living on Antarctic and South America continental shelves, we are integrating observations of larval distribution with molecular information (mt DNA, microsatellites) on historical gene flow using samples collecting on research cruises. We are also interested in establishing a baseline of patterns along the Antarctic Peninsula, a place that is warmiing faster than anywhere else on earth.
  • Hemichordate Phylogeny
    Hemichordates are an enigmatic phylum of marine worms and their relatives that are pivotal to hypotheses of deuterostome evolution and chordate origins. Hemichordates and chordates share several important morphological characters, but they are the sister group to echinoderms, which places them in a unique position for assessing character state evolution within deuterostomes. There are two currently recognized groups within hemichordata; the solitary acorn worms, or enteropneusts, and tiny colonial animals called pterobranchs. Both groups have been implicated in hypotheses regarding the early evolution of the deuterostomes, and have very different larval and adult body plans. In collaboration with Dr. Billie Swalla at the University of Washington, we are investigating phylogenetic relationships within Hemichordata, using phylogenomic (expressed sequence tag) and mitochondrial genome data. We are also investigating hemichordate diversity using more traditional molecular markers.
  • Siboglinids & chemosynthetic environments
    Because hydrothermal vent systems are hypothesized to be extreme environments that have been present since the early history of the planet, understanding the ability of organismal lineages to adapt and thrive in such environments is of interest to evolutionary biologists. The lab has been focusing on the reconstructing the phylogenetic history of key taxonomic groups to understand the origins of vent fauna and how taxa in vent environments speciate and maintain genetic communication. The primary taxon of interest has been the siboglinid tube-worms. (Siboglids were formerly recognized as vestimentiferans and pogonophorans.) These gutless worms are nourished by endosymbiotic bacteria.
  • Meiofaunal environmental genomics & hydrocarbon response
    Many of the organisms in the sea are poorly known, especially meiofauna, organisms less then 1 millimeter that live between the sediment grains. We are coupling traditional techniques of meiofaunal study with next-generation molecular approaches that allow for the rapid evaluation of meiofaunal communities on much larger scale than previously possible. In particular, we are focuing on meiofaunal communities in the Gulf of Mexico. The lab's work in the this area has grown as a response to the Deepwater Horizon oil spill diaster. In additional to examining specific hydrocarbon related events, we are taking a broader approach to understanding meiofaunal diversity.
  • Genomics & Bioinformatics
    High throughput sequencing technologies have made it possible for researchers to quickly and easily collect large amounts of DNA sequence data from virtually any organism. However, in order to interpret these data, they must be properly processed, assembled, analyzed, and visualized. Our lab is currently employing numerous bioinformatics tools in order to study metazoan evolution. These include a bioinformatics pipeline to process genome and transcriptome data for use in phylogenomic studies of animal evolutionary relationships. Additionally, as part of our study of siboglind annelids and their chemosynthetic symbionts, we are surveying the transcriptomes of the annelid hosts and sequencing the genomes of several bacterial symbionis. Gene network analyses will improve our understanding of the functional genomic basis of this symbiosis.
  • Early Evolution of Animals
    Understanding the evolution of multicellular organisms is paramount in elucidating how advanced life can come to exist. On Earth, several multicellular groups arose independently, but only animals have evolved tissues that allow active, rapid movement and fast intercellular communication. In order to discern how these features arose, we must first unravel the evolutionary relationships among the earliest animal groups and identify the genetic mechanisms responsible for creating muscle and nervous tissue. Until recently, available data supported the hypothesis that sponges, which lack muscles and nerves, are basal to all other animals. However, recent data suggest that ctenophores are the most basal animal lineage, suggesting that such systems may have evolved twice within Metazoa, possibly including different molecular toolkits in different lineages. In order to test this hypothesis, we are employing cutting edge genomic approaches to study basal metazoan evolution.
 
     
   
 
Recent Halanych Grants

 
 

Links exist to some (but not all) of the grants below. Click on the titles to activate links.

 

Cephalodiscus

Hemichordates are central to hypotheses on Deuterostome phylogeny and chordate origins. We are reconstructing the evolutionary history of this poorly known taxon.

Horses
Tubeworms from the Gulf of Mexico

Genomic approaches are being used to understand how tubeworms establish and maintain sysmbioses at a molecular level.

Worms are diverse

The relationships within annelids, one of the most diverse animal phyla, are very poorly known. Using a collaborative multitiered apporach we hope to provided insight on their evolutionary history.

Orchids
Collecting Mud but not in GoM

The Deepwater Horizon oil spill presented a major distrubance in the Gulf of Mexico. We are using genomic tools to help understand the effects of the spill on meiofauna.