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Interdisciplinary teams are on the rise as scientists attempt to address complex environmental issues. While the benefits of team science approaches are clear, researchers often struggle with its implementation, particularly for new team members. The challenges of large projects often weigh on the most vulnerable members of a team: trainees, including undergraduate students, graduate students, and post‐doctoral researchers. Trainees on big projects have to navigate their role on the team, with learning project policies, procedures, and goals, all while also training in key scientific tasks such as co‐authoring papers. To address these challenges, we created and participated in a project‐specific, graduate‐level team science course. The purposes of this course were to: (1) introduce students to the goals of the project, (2) build trainees' understanding of how big projects operate, and (3) allow trainees to explore how their research interests dovetailed with the overall project. Additionally, trainees received training regarding: (1) diversity, equity & inclusion, (2) giving and receiving feedback, and (3) effective communication. Onboarding through the team science course cultivated psychological safety and a collaborative student community across disciplines and institutions. Thus, we recommend a team science course for onboarding students to big projects to help students establish the skills necessary for collaborative research. Project‐based team science classes can benefit student advancement, enhance the productivity of the project, and accelerate the discovery of solutions to ecological issues by building community, establishing a shared project vocabulary, and building a workforce with collaborative skills to better answer ecological research questions.

 

Constraining the magnitude of past hydrological change may improve understanding and predictions of future shifts in water availability. Here we demonstrate that water-table depth, a sensitive indicator of hydroclimate, can be quantitatively reconstructed using Kr and Xe isotopes in groundwater. We present the first-ever measurements of these dissolved noble gas isotopes in groundwater at high precision (≤0.005‰ amu⁻¹; 1σ), which reveal depth-proportional signals set by gravitational settling in soil air at the time of recharge. Analyses of California groundwater successfully reproduce modern groundwater levels and indicate a 17.9 ± 1.3 m (±1 SE) decline in water-table depth in Southern California during the last deglaciation. This hydroclimatic transition from the wetter glacial period to more arid Holocene accompanies a surface warming of 6.2 ± 0.6 °C (±1 SE). This new hydroclimate proxy builds upon an existing paleo-temperature application of noble gases and may identify regions prone to future hydrological change.

 

Lanthanide (Ln) elements are utilized as cofactors for catalysis by XoxF-type methanol dehydrogenases (MDHs). A primary assumption is that XoxF enzymes produce formate from methanol oxidation, which could impact organisms that require formaldehyde for assimilation. We report genetic and phenotypic evidence showing that XoxF1 (MexAM1_1740) fromMethylobacterium extorquensAM1 produces formaldehyde, and not formate, during growth with methanol. Enzyme purified with lanthanum or neodymium oxidizes formaldehyde. However, formaldehyde oxidation via 2,6-dichlorophenol-indophenol (DCPIP) reduction is not detected in cell-free extracts from wild-type strain methanol- and lanthanum-grown cultures. Formaldehyde activating enzyme (Fae) is required for Ln methylotrophic growth, demonstrating that XoxF1-mediated production of formaldehyde is essential. Addition of exogenous lanthanum increases growth rate with methanol by 9–12% but does not correlate with changes to methanol consumption or formaldehyde accumulation. Transcriptomics analysis of lanthanum methanol growth shows upregulation ofxox1and downregulation ofmxagenes, consistent with the Ln-switch, no differential expression of formaldehyde conversion genes, downregulation of pyrroloquinoline quinone (PQQ) biosynthesis genes, and upregulation offdh4formate dehydrogenase (FDH) genes. Additionally, the Ln-dependent ethanol dehydrogenase ExaF reduces methanol sensitivity in thefaemutant strain when lanthanides are present, providing evidence for the capacity of an auxiliary role for ExaF during Ln-dependent methylotrophy.

 

Oxygen minimum zones (OMZs), large midwater regions of very low oxygen, are expected to expand as a result of climate change. While oxygen is known to be important in structuring midwater ecosystems, a precise and mechanistic understanding of the effects of oxygen on zooplankton is lacking. Zooplankton are important components of midwater food webs and biogeochemical cycles. Here, we show that, in the eastern tropical North Pacific OMZ, previously undescribed submesoscale oxygen variability has a direct effect on the distribution of many major zooplankton groups. Despite extraordinary hypoxia tolerance, many zooplankton live near their physiological limits and respond to slight (≤1%) changes in oxygen. Ocean oxygen loss (deoxygenation) may, thus, elicit major unanticipated changes to midwater ecosystem structure and function. 

Oxygen minimum zones (OMZs), large midwater regions of very low oxygen, are expected to expand as a result of climate change. While oxygen is known to be important in structuring midwater ecosystems, a precise and mechanistic understanding of the effects of oxygen on zooplankton is lacking. Zooplankton are important components of midwater food webs and biogeochemical cycles. Here, we show that, in the eastern tropical North Pacific OMZ, previously undescribed submesoscale oxygen variability has a direct effect on the distribution of many major zooplankton groups. Despite extraordinary hypoxia tolerance, many zooplankton live near their physiological limits and respond to slight (≤1%) changes in oxygen. Ocean oxygen loss (deoxygenation) may, thus, elicit major unanticipated changes to midwater ecosystem structure and function.