Research Statement
We live at a critical time for biodiversity. The biosphere is undergoing profound alterations as a result of human activities, with a mass extinction erasing much of our biological heritage before it is even documented. My research program is defined by the biodiversity crisis. Documenting life on Earth before it is profoundly altered is one of the most relevant research endeavors for our generation. As scientific methods advance over time, our ability to understand the world increases in most fields, thus current research efforts will be inevitably overshadowed by future progress. However, as biodiversity is lost over time, our ability to document the pre-human biosphere decreases, making current efforts irreplaceable. I study biodiversity in the coastal ocean, especially on coral reefs and the North Pacific with a two-pronged approach: documenting species diversity with large-scale biodiversity surveys, and testing hypotheses about historical origins of diversity using paleontological, ecological, and phylogenetic tools.
Research Interests
Biogeography, evolution, systematics, and natural history of invertebrates. Marine biodiversity and biogeography, especially of tropics, coral reefs, and the North Pacific. Dynamics of species diversity and distributions; marine speciation. Large-scale marine biodiversity surveys. Island biology; marine and terrestrial biota of Pacific islands.
Documenting Marine Biodiversity
Much of our research program is focused on documenting marine diversity in the coastal ocean, especially on coral reefs. Marine biodiversity is poorly known – even estimates of how many animal species are in the ocean vary over an order of magnitude. Many species, especially on endangered habitats like coral reefs, face decline and extinction with the accelerating impact of climate change and other human impacts. Our group documents marine biodiversity through large-scale, collaborative marine biodiversity surveys – “bioblitzes” – as well as smaller efforts as opportunities permit. Focus has been on the tropical Indo-West Pacific (IWP) and temperate Northeast Pacific, but we have also carried out surveys in other regions. The IWP is the largest and most diverse marine biogeographic region, extends from the Red Sea and East Africa to the remote islands of Pacific Oceania, and includes most of the world’s coral reefs and reef diversity.
The goal of bioblitzes is to record, voucher, image, and sequence the biota of a selected area. We aim to “triple-document” the diversity of an area in morphological vouchers suitable for taxonomic study, images that show the live appearance of species and provide ready field guides, and tissues that yield DNA barcodes and genomic sequences that permit rapid analysis of species boundaries and relationships. Surveys are collaborative efforts, carried out typically with teams of 5-20 taxonomists, field workers, and students in an effort that lasts from a week to a month or more. A typical 2-3-week effort nets about a thousand species. We focus mostly on macroinvertebrates, but microfauna has also been included in some surveys. Taxonomic coverage depends on participants but tends to be broad across the phyla. Specimens are sorted to morpho-species in the field, so most can be triple-documented. Symbionts are targeted and host associations tracked. Tissues resulting from recent surveys are routinely sequenced for the COI DNA barcode region, mostly by Chris Meyer’s lab at the Smithsonian. Species are identified and described through our network of collaborating taxonomists. Vouchers, images, and sequences are made broadly available, and we actively solicit taxonomists to study the collections. Our lab also pursue taxonomic studies, especially on sea cucumbers, but also on other echinoderms, crustaceans, mollusks, and other taxa.
We have carried out large and small surveys in many areas, with current work focused on the Arabian region (Red Sea and Oman) and the NE Pacific. The Arabian surveys started in 1999 in Oman and have gained momentum with a long-term (2013-) collaboration with the Red Sea Research Center at KAUST, and a PurSUiT grant from NSF focused on Oman (2019-2024). This effort is documenting the marine diversity around the Arabian peninsula, one of the most environmentally-heterogeneous areas in the world ocean. The region has reefs in crystal clear, oligotrophic waters in the northern Red Sea, mixed reef-macroalgal habitats in the upwelling systems of the Arabian Sea coast in Oman, and reefs experiencing the highest temperatures and salinities in the Arabian/Persian Gulf. This environmental variation has fueled local adaptation, differentiation, diversification, and high spatial turnover in the biota.
The NE Pacific surveys started with a gradual specimen-based study of the San Juan Islands’ fauna (Friday Harbor Labs, WA 2007-) and has involved surveys in British Columbia (with Hakai Institute, 2017-), Salish Sea (with WA Dept of Ecology, 2019), central Oregon coast (with Oregon Institute of Marine Biology, 2019), and S California (with the Natural History Museum of LA, 2019), so far, with plans for additional surveys from S California to Alaska. The goal of this large, broadly collaborative effort is to create a species-level, information-rich inventory of the NE Pacific coastal invertebrate fauna. This is one of the best-known parts of the ocean but still abounds in new and poorly understood taxa. It also provides a great laboratory for understanding latitudinal gradients, diversification, and response to climate change.
Samples from surveys are used by our group to study the how the diversity and distribution of marine organisms evolved through speciation, extinction, and changing species ranges. Much of this work is focused on reef faunas. Reefs are potentially the most diverse marine habitats on Earth, and the IWP is the most diverse marine biogeographic region. Striking gradients characterize the diversity of the IWP, peaking in the Australasian region and decreasing peripherally. We use genetic tools to document the differentiation of species across this vast area. Initial divergence of the most species we have studied is geographic, such that sister taxa have allopatric ranges. The distribution and genetic divergence of pairs of sister taxa reflect the spatial and temporal divergence that formed them and is used to test hypotheses about the drivers of diversification.
Selected Publications
Hernández-Díaz, Y. Q., Solís-Marín, F. A., Beltrán-López, R. G., Benítez, H. A., Díaz-Jaimes, P., Paulay, G. 2023. Integrative species delimitation in the common ophiuroid Ophiothrix (Ophiothrix) angulata (Echinodermata: Ophiuroidea): insights from COI and geometric morphometrics in the West coast of the North Atlantic Ocean. PeerJ 11: e15655 https://doi.org/10.7717/peerj.15655
Samimi-Namin, K., Claereboudt, M.R., Hoeksema, B.W., McFadden, C.S., Bezio, N., Paulay, G. 2023. Aggregations of a sessile ctenophore, Coeloplana sp., on Indo-West Pacific gorgonians. Diversity 15(10): 1060 https://doi.org/10.3390/d15101060
Lasley, R.M.Jr, Evans, N., Paulay, G., Michonneau, F., Windsor, A., Irwansyah, Ng, P. 2023. Allopatric mosaics in the Indo-West Pacific crab subfamily Chlorodiellinae reveal correlated patterns of sympatry, genetic divergence, and genitalic disparity. Molecular Phylogenetics & Evolution 181: 107710 https://doi.org/10.1016/j.ympev.2023.107710
Xu, T., Bravo, H., Paulay, G., van der Meij, S.E.T. 2021. Diversification and distribution of gall crabs (Brachyura: Cryptochiridae: Opecarcinus) associated with Agariciidae corals. Coral Reefs https://doi.org/10.1007/s00338-021-02163-1
Filho, H.G., Paulay, G., Krug, P.J. 2019. Eggs sunny-side up: A new species of Olea, an unusual oophagus sea slug (Gastropoda: Heterobranchia: Sacoglossa), from the western Atlantic. Zootaxa 4614 (3): 541–565
Miller, A., Kerr, A., Paulay, G., Reich, M., Carvajal, J., Wilson, N., Rouse, G. 2017. Molecular Phylogeny of Extant Holothuroidea (Echinodermata). Molecular Phylogenetics and Evolution 111: 110-131 https://doi.org/10.1016/j.ympev.2017.02.014
DiBattista J.D., Choat, J. H., Gaither, M.R., Hobbs, J-P.A., Lozano-Cortés, D.F., Myers, R.F., Paulay, G., Rocha, L.A., Toonen, R.J., Westneat, M.W., Berumen, M.L., 2016. On the origin of endemic species in the Red Sea. Journal of Biogeography 43:13-30
Duffy, J.E., Amaral-Zettler, L.A., Fautin, D. G., Paulay, G., Rynearson, T., Sosik, H.M., Stachowicz, J.J. 2013. Envisioning a National Marine Biodiversity Observation Network. BioScience 63: 350-361, DOI: 10.1525/bio.2013.63.5.8
Kim, S.W., Kerr, A.M., Paulay, G. 2013. Color, confusion, and crossing: resolution of species problems in Bohadschia (Echinodermata: Holothuroidea). Zoological Journal of the Linnean Society 168: 81-97
Paulay, G., Starmer, J. 2011. Evolution, insular restriction, and extinction of oceanic land crabs, exemplified by the loss of an endemic Geograpsus in Hawai’i. PLoS One 6(5): e19916. doi:10.1371/journal.pone.0019916.
Malay. M. C.; Paulay, G. 2010. Peripatric speciation drives diversification and distributional pattern of reef hermit crabs (Decapoda: Diogenidae: Calcinus). Evolution 64: 634-662. https://doi.org/10.1111/j.1558-5646.2009.00848.x . Featured in Editor’s Choice in Science 327: 1555.
Meyer, C. P.; Paulay, G. 2005. DNA Barcoding: error rates based on comprehensive sampling. Public Library of Science, Biology 3(12): e422.
Meyer, C. P.; Geller, J. B.; Paulay, G. 2005 Fine scale endemism on coral reefs: archipelagic differentiation in turbinid gastropods. Evolution 59: 113-125.
Paulay, G. (ed.) 2003. The marine biodiversity of Guam and the Marianas. Micronesica 35-36: 1-682.
Paulay, G.; Kirkendale, L. ; Lambert, G.; Meyer, C. 2002. Anthropogenic biotic interchange in a coral reef ecosystem: a case study from Guam. Pacific Science 56: 403-422. doi:10.1353/psc.2002.0036.
Paulay, G. 1997. Diversity and distribution of reef organisms. In: Birkeland, C. (ed.). Life and death of coral reefs. Chapman & Hall, NY, pp. 298-353
Paulay, G. 1996. Dynamic clams: changes in the bivalve fauna of Pacific islands as a result of sea level fluctuations. American Malacological Bulletin 12: 45-57
Paulay, G. 1994. Biodiversity on oceanic islands: its origin and extinction. American Zoologist 34: 134-144
Paulay, G., McEdward, L. R. 1990. A simulation model of island reef morphology: the effects of sea level fluctuations, growth, subsidence, and erosion. Coral Reefs 9: 51-62
Paulay, G. 1990. Effects of late Cenozoic sea-level fluctuations on the bivalve faunas of tropical oceanic islands. Paleobiology 16: 415-434
Paulay, G. 1985. Adaptive radiation on an isolated oceanic island: the Cryptorhynchinae (Curculionidae) of Rapa revisited. Biological Journal of the Linnean Society 26: 95-187
See ResearchGate for other publications