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The goal of QUantifying Interocean fluxes in the Cape Cauldron Hotspot of Eddy kinetic energy (QUICCHE) was to observe mixing and stirring in the Cape Basin in the southeast Atlantic Ocean across time and space scales ranging from seconds to months and from centimeters to tens of kilometers using a variety of sensors and platforms. As part of QUICCHE, two inverted echo sounders equipped with bottom pressure gauges and current meters (CPIES) were deployed at sites designated CP01 and CP02 at 4676 and 4895 m depth respectively, from March 2023 to April 2024. The CPIES data are the highest quality versions with the least amount of processing. The collection and processing of the data are described in the report provided. Data are in NetCDF. 

Abstract Cross-frontal exchange facilitated by mesoscale eddies in the lee of major topographic features of the Southern Ocean is fundamental to the global overturning circulation. Despite the outsize importance for meridional heat flux, we lack an accurate estimation of fluxes across the Antarctic Circumpolar Current (ACC) due to the challenges of observing mesoscale eddy fluctuations on the temporal and spatial scales required. Here, 12 years of Argo data are used to observe patterns of cross-frontal exchange in the Southeast Indian Ridge system, a relatively underobserved region, known to be a hotspot of exchange. Spice variance along ACC streamlines is used as a proxy for cross-frontal exchange. Elevated exchange is observed downstream of the ridge system in nearly every streamline and is particularly prominent in the core of the ACC. Notably, exchange peaks progressively downstream at each poleward streamline suggesting a systematic north-to-south handoff across nearly the full breadth of the ACC. Employing a mixing length framework, lateral stirring is parameterized as an eddy diffusivity on the isopycnal of peak exchange. We find a highly localized pattern of diffusivity, peaking between the crest and trough of the first standing meander in the lee of the ridge system. Spatially, this diffusivity pattern correlates with an along-stream increase in eddy kinetic energy. Along-stream vertical wavenumber spectra of spice anomaly profiles indicate that the vertical scales of intrusions, which are initially large (approximately 800 m), rapidly evolve downstream to smaller wavenumbers (100–300 m) presumably in response to intense vertical shear and filamentation. 

Summary The timing of a developmental transition (phenology) can influence the environment experienced by subsequent life stages. When phenology causes an organism to occupy a particular habitat as a consequence of the developmental cues used, it can act as a form of habitat tracking. Evolutionary theory predicts that habitat tracking can alter the strength, direction, and mode of natural selection on subsequently expressed traits.To test whether germination phenology altered natural selection on postgermination traits, we manipulated germination time by planting seedlings in seven germination cohorts spanning 2 yr. We measured selection on postgermination traits relating to drought, freezing, and heat tolerance using a diverse combination ofArabidopsis thalianamutants and naturally occurring ecotypes.Germination cohorts experienced variable selection: when dry, cold, and hot environments were experienced by seedlings, selection was intensified for drought, freezing, and heat tolerance, respectively. Reciprocally, postgermination traits modified the optimal germination time; genotypes had maximum fitness after germinating in environments that matched their physiological tolerances.Our results support the theoretical predictions of feedbacks between habitat tracking and traits expressed after habitat selection. In natural populations, whether phenological shifts alter selection on subsequently expressed traits will depend on the effectiveness of habitat tracking through phenology. 

Abstract Evolvable traits of organisms can alter the environment those organisms experience. While it is well appreciated that those modified environments can influence natural selection to which organisms are exposed, they can also influence the expression of genetic variances and covariances of traits under selection. When genetic variance and covariance change in response to changes in the evolving, modified environment, rates and outcomes of evolution also change. Here we discuss the basic mechanisms whereby organisms modify their environments, review how those modified environments have been shown to alter genetic variance and covariance, and discuss potential evolutionary consequences of such dynamics. With these dynamics, responses to selection can be more rapid and sustained, leading to more extreme phenotypes, or they can be slower and truncated, leading to more conserved phenotypes. Patterns of correlated selection can also change, leading to greater or less evolutionary independence of traits, or even causing convergence or divergence of traits, even when selection on them is consistent across environments. Developing evolutionary models that incorporate changes in genetic variances and covariances when environments themselves evolve requires developing methods to predict how genetic parameters respond to environments—frequently multifactorial environments. It also requires a population-level analysis of how traits of collections of individuals modify environments for themselves and/or others in a population, possibly in spatially explicit ways. Despite the challenges of elucidating the mechanisms and nuances of these processes, even qualitative predictions of how environment-modifying traits alter evolutionary potential are likely to improve projections of evolutionary outcomes. 

PremiseThe success or failure of propagules in contrasting microhabitats may play a role in biological invasion. We tested for variation in demographic performance and phenotypic trait expression during invasion byAlliaria petiolatain different microhabitats. MethodsWe performed a reciprocal transplant experiment withAlliaria petiolatafrom edge, intermediate, and forest understory microhabitats to determine the roles of the environment and maternal source on traits, fecundity, population growth rates (λ), and selection. ResultsObservations ofin situpopulations show that edge populations had the highest density and reproductive output, and forest populations had the lowest. In experimental populations, population growth rates and reproductive output were highest in the edge, and the intermediate habitat had the lowest germination and juvenile survival. Traits exhibited phenotypic plasticity in response to microhabitat, but that plasticity was not adaptive. There were few effects of maternal source location on fitness components or traits. ConclusionsAlliaria petiolataappears to be viable, or nearly so, in all three microhabitat types, with edge populations likely providing seed to the other microhabitats. The intermediate microhabitat may filter propagules at the seed stage, but discrepancies betweenin situobservations and experimental transplants preclude clear conclusions about the role of each microhabitat in niche expansion. However, edge microhabitats show the highest seed output in both analyses, suggesting that managing edge habitats might reduce spread to the forest understory.