Systematic review and meta-analysis of 50 years of coral disease research visualized through the scope of network theory

Abstract

Coral disease research encompasses five decades of undeniable progress. Since the first descriptions of anomalous signs, we have come to understand multiple processes and environmental drivers that interact with coral pathologies. In order to gain a better insight into the knowledge we already have, we explored how key topics in coral disease research have been related to each other using network analysis. We reviewed 719 papers and conference proceedings published from 1965 to 2017. From each study, four elements determined our network nodes: (1) studied disease(s); (2) host genus; (3) marine ecoregion(s) associated with the study site; and (4) research objectives. Basic properties of this network confirmed that there is a set of specific topics comprising the majority of research. The top five diseases, genera, and ecoregions studied accounted for over 48% of the research effort in all cases. The community structure analysis identified 15 clusters of topics with different degrees of overlap among them. These clusters represent the typical sets of elements that appear together for a given study. Our results show that while some coral diseases have been studied considering multiple aspects, the overall trend is for most diseases to be understood under a limited range of approaches, e.g., bacterial assemblages have been considerably studied in Yellow and Black band diseases while immune response has been better examined for the aspergillosis-Gorgonia system. Thus, our challenge in the near future is to identify and resolve potential gaps in order to achieve a more comprehensive progress on coral disease research.

Influence of number of individuals and observations per individual on a model of community structure

“…It is likely that increasing connectivity among communities despite high densities of connections within subgroups, as is typical in fission-fusion societies, negatively influences our ability to correctly assort individuals to a subgroup. A modification of R com has been suggested for instances where an individual is a part of multiple communities simultaneously [ 35 ], and perhaps a similar modification is needed for societies displaying fission-fusion dynamics. Further study is necessary to determine how both network size and structure can influence the consequences of sampling and data filtering prior to generating network models based on a portion of the overall population [ 17 , 19 ].…”

“…All sample networks were based on randomly selecting a subset of individuals and observations from the above generated 'observed' network. Individuals were randomly sampled to generate subsets of 5,10,15,20,25,35,50,75, and 99 (all) individuals. Within each of these network sizes, we randomly selected 1, 5, 15, 10, 20, 30, or 40 (all available from 'observed' network) observations for each individual to generate balanced sample networks.…”

Contrasting reproductive strategies of two Hawaiian Montipora corals

“…Coral reefs and other marine fauna are facing unparalleled threats to their future integrity due to the dual consequences of ocean acidification and warming from climate change 1 – 3 , local habitat degradation 4 , and emergent diseases 5 , 6 . The persistence of these populations in the Anthropocene will hinge upon their ability to survive and successfully reproduce.…”

Metabolomics of Healthy and Stony Coral Tissue Loss Disease Affected Montastraea cavernosa Corals

“…Coral reefs provide a variety of important services, including hosting diverse marine ecosystems (Plaisance et al, 2011;Fisher et al, 2015), supplying pharmacophores for drug development (Bruckner, 2002;Sang et al, 2019), protecting shorelines (Reguero et al, 2021), and contributing to coastal economies with an estimated collective worth of $3.4 billion in the US (Brander and Van Beukering, 2013). Factors including increased ocean temperatures, ocean acidification, pollution, and disease outbreaks present continual challenges to the health of corals (Richardson, 1998;Rosenberg and Ben-Haim, 2002;Rogers and Weil, 2010;Pandolfi et al, 2011;Hoegh-Guldberg et al, 2017;Grottoli et al, 2018;Montilla et al, 2019;Howells et al, 2020). A combination of environmental stressors can increase the vulnerability of corals to disease outbreaks (Maynard et al, 2015;Benkwitt et al, 2020).…”