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Abstract AimAlthough species richness globally is likely to be declining, patterns in diversity at the regional scale depend on species gains within new habitats and species losses from previously inhabited areas. Our understanding of the processes associated with gains or losses remains poor, including whether these events exhibit immediate or delayed responses to environmental change. LocationThe study focuses on nine temperate marine ecosystems in North America. Time periodThe study period varies by region, but overall encompasses observations from 1970 to 2014. Major taxa studiedWe identified regional gains and losses for 577 marine fish and invertebrate species. MethodsFrom a total of 166,213 sampling events from bottom trawls across North America that informed 17,997 independent observations of species gains and losses, we built generalized linear mixed effects models to test whether lagged temperature can explain instances of gains and losses of marine fishes and invertebrates in North American continental shelf habitats. ResultsWe found that gains were less likely in years with high seasonality, consistent with seasonal extremes as a strong constraint on species occurrence. Losses were also negatively associated with high seasonality, but the response was delayed by 3 years. Main conclusionsEnvironmental conditions play a role in species occupancy across diverse temperate marine ecosystems. Immediate gains paired with delayed losses can drive transient increases in species richness during times of environmental change. Identifying the dynamics behind regional species gains and losses is an important step towards prediction of biodiversity changes across ecosystems.
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Diversity squared: New insights into patterns of heterobranch species richness and diversification of lineages
Expeditionary field work still remains the most fundamental tool to discover novel species and repetitive sampling in high diversity portions of the Indo-Pacific tropics continues to provide large numbers of previously undocumented taxa. Multidisciplinary collaborative teams and large expeditions are an immense source of novel biodiversity. Micro-scale temporal changes in diverse ecosystems provide a catalyst for new species discovery, as well as insights into the discovery of patterns of trophic and symbiotic divergence. Additionally, phylogenetic analyses of large samples of diverse taxa across geographical gradients have increasingly detected cryptic and pseudo-cryptic species complexes that have dramatically altered our view of species richness. Aposematic and extreme camouflaged colour patterns within the context of fish predatory behaviour provides an evolutionary framework for divergence and convergence of colour patterns. Similarly, recent studies of temperate nudibranch assemblages in temperate waters in Europe, southern Africa and the Pacific coast of North America also demonstrate previously undetected diversity and the presence of colour patterns that likely reflect similarity derived from both common ancestry and convergence. Combining these approaches has documented astonishingly high levels of previously undetected diversity, has huge implications to our knowledge of global biodiversity with a likely 3-5x increase in global species richness, and has developed more appropriate regenerative conservation strategies.
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- Award ID(s):
- 1856407
- PAR ID:
- 10349314
- Date Published:
- Journal Name:
- Spixiana Supplement
- Volume:
- 30A
- ISSN:
- 0177-7424
- Page Range / eLocation ID:
- 33
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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