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Byline: Mandeep. Singh, Deepika. Verma, Tirtha. Banerjee, Ankita. Singh, Kanika. Bhatt Purpose: Coronavirus outbreak was first reported towards the end of 2019 and has now been declared a pandemic by [...]

Butterfly wings display a diversity of cell types, including large polyploid scale cells, yet the molecular basis of such diversity is poorly understood. To explore scale cell diversity at a transcriptomic level, we employ single-cell RNA sequencing of ∼5,200 large cells (>6 μm) from 22.5- to 25-h male pupal forewings of the butterfly Bicyclus anynana. Using unsupervised clustering, followed by in situhybridization, immunofluorescence, and CRISPR-Cas9 editing of candidate genes, we annotate various cell types on the wing. We identify genes marking non-innervated scale cells, pheromone-producing glandular cells, and innervated sensory cell types. We show that senseless, a zinc-finger transcription factor, and HR38, a hormone receptor, determine the identity, size, and color of different scale cell types and are important regulators of scale cell differentiation. This dataset and the identification of various wing cell-type markers provide a foundation to compare and explore scale cell-type diversification across arthropod species.

Partitioning evapotranspiration (ET) into its primary components, that is, evaporation (E) and plant transpiration (T), is needed in a range of hydrometeorological applications. Using vegetation index (VI) to obtain spatially resolved T:ET ratio over large areas has emerged as a promising approach in this regard. Here, we assess the effectiveness of this approach in differently managed wheat systems. Results show a weak relation between T:ET and VI in disturbed (i.e., grazed) systems. Furthermore, flux partition based on a canonical T:ET versus VI relation or the relation derived in a neighboring undisturbed wheat system introduce large errors in disturbed systems, thus underscoring the limits on the transferability of the VI‐based ET partitioning approach. The effectiveness of the VI‐based approach is found to be related to the strength of correlation between VI and vapor pressure deficit and/or radiation. This correlation metric can help identify settings where the approach is likely to be effective. Evapotranspiration (ET) plays a significant role in water and climate cycles by affecting the energy and water balance over the land surface which in turn mediates the land‐atmosphere interactions. ET is composed of two primary components that is, direct evaporation (E) and plant transpiration (T). Partitioning total ET into its individual components (Eand T) is of significant importance for better assessment of both regional and global water budgets. One of the primary approaches to partition ET over large areas is by using vegetation indices (VI), which indirectly capture plants' biophysical state. This approach has been used to partition ET in different landscapes, but its efficacy has not been tested in disturbed ecosystems, which cover a large fraction of Earth's vegetated area. Here, we assess the effectiveness of this VI‐based ET partitioning approach in disturbed (i.e., grazed) ecosystems. We find that the VI‐based ET partitioning introduces large errors in disturbed systems. Further investigation identifies conditions that can be used to filter‐out regions where the VI‐based partition is likely to be more (or less) effective. Three Evapotranspiration (ET) partitioning methods were used to partition ET in differently managed wheat systemsGrazing altered the relation between T:ET and enhanced vegetation indexET partitioning errors were higher in disturbed (i.e., grazed) systems Three Evapotranspiration (ET) partitioning methods were used to partition ET in differently managed wheat systems Grazing altered the relation between T:ET and enhanced vegetation index ET partitioning errors were higher in disturbed (i.e., grazed) systems

Butterfly wing scales can develop intricate cuticular nanostructures that produce silver colors, but the underlying genetic and physical basis of such colors is mostly unexplored. Here, we characterize different types of wild-type silver scales in Bicyclus anynanabutterflies and show that the varying thickness of the air layer between two cuticular laminas is most important for producing silvery broadband reflectance. We then address the function of five genes—apterous A, Ultrabithorax, doublesex, Antennapedia, and optix—in silver scale development by examining crispants with either ectopic gains or losses of silver scales. Simultaneous transformations of three parameters—loss of the upper lamina, increased lower lamina thickness, and increased pigmentation—occur when silver scales become brown and vice versa when brown scales become silver. Antennapediaand optixare high-level regulators of different silver scale types and determine cell shape in both sexes. Moreover, Antennapediais involved in determining ridge and crossrib orientation.

Momentum and mass exchanges between the atmosphere and forests situated on complex terrain continue to draw significant research attention primarily because of their significance to a plethora of applications. In this paper, we investigated flows behavior on the leeward side of a two‐dimensional forested ridge under neutrally stratified conditions using large‐eddy simulations (LESs). The goal is to understand how variations in leaf area index (LAI), vertical canopy foliage distributions, and forest edge positions affect mean/turbulent flow statistics, momentum fluxes, and onset of recirculation patterns. Although pressure perturbations are dominated by the hill shape, it is demonstrated here that changes in canopy foliage distribution modulate intensities and patterns of the leeward adverse pressure gradients. Such changes in the adverse pressure gradients alter the mean velocity streamlines including the patterns and magnitudes of the leeward downward mean vertical velocity and the velocity variances and momentum flux in the wake region. While a downwind recirculation zone develops in all cases, the details regarding the incipient location and recirculation zone size vary including positions of the separation and reattachment points. Furthermore, changes in the strength and depth of the zone occur due to canopy‐induced changes in adverse pressure gradients, advection, and canopy drag. Because the recirculation zone impacts the local mean advective terms in momentum and scalar exchanges, the simulations here indicate that canopy morphology‐induced changes in the leeward flows have significant implications to both measurements and models of biosphere‐atmosphere exchange over complex terrain. Flows over the leeward side of a partially and fully forested hill are studied using a multiple‐layer canopy module in the WRF‐LESCanopy morphologies and partial forest cover lead to pressure perturbations that deviate from hydrostatic approximationThe leeward recirculation is altered by canopy morphological changes and partily modulated the pressure‐velocity interaction