Reproduction and Genetic Structure in a Reef-Forming Glass Sponge, Aphrocallistes vastus

• Author / Creator

  Brown, Rachel R

• Reef-forming glass sponges are ecosystem engineers that provide habitat for a diverse assemblage of benthic marine species. Sixteen glass sponge reefs have recently been discovered at 100-200 m depth off the coast of British Columbia, Canada and are of conservation interest. Nothing is known of the genetic diversity or connectivity of these glass sponge populations or the extent of clonality, details that would better inform the design of protected areas. Previous work on the primary reef-forming species in the Strait of Georgia (SoG), Aphrocallistes vastus, has faced challenges in developing non-duplicated (diploid) markers. Here I develop a panel of single-copy, informative single nucleotide polymorphism (SNP) markers using a novel technique involving next generation sequencing (NGS). I examine the genetic structure of A. vastus at both reef and non-reef sites at multiple scales: 1) across individuals sampled within and between clumps in reefs, 2) between reefs, and 3) between sites within and outside the SoG. I show that the reefs are formed through sexual reproduction. Within a reef, and even within the SoG basin, genetic distance between individuals does not vary according to geographic distance, suggesting the presence of larvae that disperse throughout the SoG. Importantly, populations within the SoG are genetically distinct from populations in Barkley Sound, west of Vancouver Island. These results highlight the effectiveness of a new NGS methodology for overcoming problems posed by genomic duplication in some invertebrates, emphasize genetic mixing across reefs, and provide a baseline of connectivity that can provide insight into the management requirements of marine protected areas currently under discussion.

• Subjects / Keywords

  • Genomic Duplication
  • Larval dispersal
  • Single Nucleotide Polymorphisms
  • Ion Torrent
  • Next generation sequencing
  • Deep sea
  • Glass sponge
  • Population Genetics

• Graduation date

  Fall 2015

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R36T0H44X

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.