Microplastics are ubiquitous across ecosystems, yet the exposure risk to humans is unresolved. Focusing on the American diet, we evaluated the number of microplastic particles in commonly consumed foods in relation to their recommended daily intake. The potential for microplastic inhalation and how the source of drinking water may affect microplastic consumption were also explored. Our analysis used 402 data points from 26 studies, which represents over 3600 processed samples. Evaluating approximately 15% of Americans’ caloric intake, we estimate that annual microplastics consumption ranges from 39000 to 52000 particles depending on age and sex. These estimates increase to 74000 and 121000 when inhalation is considered. Additionally, individuals who meet their recommended water intake through only bottled sources may be ingesting an additional 90000 microplastics annually, compared to 4000 microplastics for those who consume only tap water. These estimates are subject to large amounts of variation; however, given methodological and data limitations, these values are likely underestimates.

Measurements in a coastal inlet revealed turbulence that was three to four orders of magnitude larger during the dusk ascent of a dense acoustic-scattering layer of krill than during the day, elevating daily-averaged mixing in the inlet by a factor of 100. Because vertically migrating layers of swimming organisms are found in much of the ocean, biologically generated turbulence may affect (i) the transport of inorganic nutrients to the often nutrient-depleted surface layer from underlying nutrient-rich stratified waters to affect biological productivity and (ii) the exchange of atmospheric gases such as CO2 with the stratified ocean interior, which has no direct communication with the atmosphere.

Despite a relatively short history, the field of seamount ecology is rife with ecological paradigms, many of which have already become cemented in the scientific literature and in the minds of advocates for seamount protection. Together, these paradigms have created a widely held view of seamounts as unique environments, hotspots of biodiversity and endemicity, and fragile ecosystems of exceptional ecological worth. However, closer examination reveals significant gaps in our knowledge, thereby calling the accuracy of some of these paradigms into question. Here, we review the evolution of the major paradigms in seamount ecology, assess their status against the weight of existing evidence to date, identify emerging paradigms, and suggest future research directions. We find the assertions that seamount communities are vulnerable to fishing, and that these communities have high sensitivity and low resilience to bottom trawling disturbance are well supported by existing data. We find plausible evidence that seamounts are stepping stones for dispersal, oases of abundance and biomass, and hotspots of species richness. Nonetheless, the poor sampling coverage of these discrete but globally distributed environments prevents us from accepting these ideas as paradigms. Also plausible, but requiring further investigation, are the emerging paradigms that seamount communities are structurally distinct, that populations of invertebrates on seamounts are the source of propagules for nearby slope sinks, and that seamounts have acted and can act as biological refugia from large‐scale catastrophic environmental events. In contrast, the generalizations that seamounts are island habitats with highly endemic faunas that comprise unique communities distinct in species composition from other deep‐sea habitats, and that they have high production supported by localized bottom‐up forcing, are not supported by the weight of existing evidence.

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