Mr Cameron Walsh1, Dr. Molly Timmers1,2, Ms. Katherine Viehl1, Dr. Jan Vicente1, Dr. Mykle Hoban1, Ms. Cameron Angulo1, Dr. Rob Toonen1, Dr. Brian Bowen1
1Hawaiʻi Institute of Marine Biology, Kāneʻohe, 2Pristine Seas, National Geographic Society, Washington, USA
Biography:
Cameron is a PhD candidate in the ToBo Lab of the Hawaii Institute of Marine Biology at the University of Hawaii where he studies the evolution, distribution, and ecology of marine organisms using genetics. Before moving to Hawaii for his PhD, Cameron got his B.Sc. from St. Francis Xavier University near where he grew up in Prince Edward Island (Canada) and subsequently completed the Erasmus Mundus Master Programme in Evolutionary Biology across the Netherlands, France, and Germany.
Abstract:
DNA metabarcoding of environmental water samples is becoming a widely used method to study marine communities. The cytochrome c oxidase subunit I (COI) mitochondrial gene is considered to be the standard DNA barcode region for metazoans and is widely used in metabarcoding studies. However, recent studies using bulk tissue have found that an entire class and several orders of sponges cannot be detected using COI metabarcoding, while a newly developed 28S rRNA primer set can detect considerably more sponge and benthic metazoan taxa. In this study, we conducted COI and 28S eDNA metabarcoding on the same set of water samples collected from tropical coral reef environments in the Pacific and Atlantic Oceans. Most COI reads corresponded to copepods and algae, while most 28S reads corresponded to bacteria, algae, and sponges. Both primer sets yielded a similar number of overall OTUs, however 28S metabarcoding detected several times more sponge, mollusc, annelid, cnidarian, and even diatom taxa than COI metabarcoding. The COI primer set on the other hand, yielded several times more arthropod taxa than the 28S primers. Despite having been developed and validated primarily for sponge metabarcoding, this 28S primer set detects more taxonomic diversity than COI metabarcoding across several important groups of marine invertebrates in different ocean basins. Further use of this 28S primer set in eDNA metabarcoding studies could increase the efficacy of marine biodiversity surveys around the world.