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ABSTRACT Functional studies of host-microbe interactions benefit from natural model systems that enable the exploration of molecular mechanisms at the host-microbe interface. BioluminescentVibrio fischericolonize the light organ of the Hawaiian bobtail squid,Euprymna scolopes, and this binary model has enabled advances in understanding host-microbe communication, colonization specificity,in vivobiofilms, intraspecific competition, and quorum sensing. The hummingbird bobtail squid,Euprymna berryi,can be generationally bred and maintained in lab settings and has had multiple genes deleted by CRISPR approaches. The prospect of expanding the utility of the light organ model system by producing multigenerational host lines led us to determine the extent to which theE. berryilight organ symbiosis parallels known processes inE. scolopes. However, the nature of theE. berryilight organ, including its microbial constituency and specificity for microbial partners, has not been examined. In this report, we isolated bacteria fromE. berryianimals and tank water. Assays of bacterial behaviors required in the host, as well as host responses to bacterial colonization, illustrate largely parallel phenotypes inE. berryiandE. scolopeshatchlings. This study revealsE. berryito be a valuable comparative model to complement studies inE. scolopes.IMPORTANCEMicrobiome studies have been substantially advanced by model systems that enable functional interrogation of the roles of the partners and the molecular communication between those partners. TheEuprymna scolopes-Vibrio fischerisystem has contributed foundational knowledge, revealing key roles for bacterial quorum sensing broadly and in animal hosts, for bacteria in stimulating animal development, for bacterial motility in accessing host sites, and forin vivobiofilm formation in development and specificity of an animal’s microbiome.Euprymna berryiis a second bobtail squid host, and one that has recently been shown to be robust to laboratory husbandry and amenable to gene knockout. This study identifiesE. berryias a strong symbiosis model host due to features that are conserved with those ofE. scolopes, which will enable the extension of functional studies in bobtail squid symbioses. 

Summary Structural color is poorly known in plants relative to animals. In fruits, only a handful of cases have been described, including inViburnum tinuswhere the blue color results from a disordered multilayered reflector made of lipid droplets. Here, we examine the broader evolutionary context of fruit structural color across the genusViburnum.We obtained fresh and herbarium fruit material from 30Viburnumspecies spanning the phylogeny and used transmission electron microscopy, optical simulations, and ancestral state reconstruction to identify the presence/absence of photonic structures in each species, understand the mechanism producing structural color in newly identified species, relate the development of cell wall structure to reflectance inViburnum dentatum, and describe the evolution of cell wall architecture acrossViburnum.We identify at least two (possibly three) origins of blue fruit color inViburnumin species which produce large photonic structures made of lipid droplets embedded in the cell wall and which reflect blue light.Examining the full spectrum of mechanisms producing color in pl, including structural color as well as pigments, will yield further insights into the diversity, ecology, and evolution of fruit color. 

We performed a comprehensive demographic study of the CO extent relative to dust of the disk population in the Lupus clouds in order to find indications of dust evolution and possible correlations with other disk properties. We increased the number of disks of the region with measured R CO and R dust from observations with the Atacama Large Millimeter/submillimeter Array to 42, based on the gas emission in the 12 CO J = 2−1 rotational transition and large dust grains emission at ~0.89 mm. The CO integrated emission map is modeled with an elliptical Gaussian or Nuker function, depending on the quantified residuals; the continuum is fit to a Nuker profile from interferometric modeling. The CO and dust sizes, namely the radii enclosing a certain fraction of the respective total flux (e.g., R 68% ), are inferred from the modeling. The CO emission is more extended than the dust continuum, with a R 68% CO / R 68% dust median value of 2.5, for the entire population and for a subsample with high completeness. Six disks, around 15% of the Lupus disk population, have a size ratio above 4. Based on thermo-chemical modeling, this value can only be explained if the disk has undergone grain growth and radial drift. These disks do not have unusual properties, and their properties spread across the population’s ranges of stellar mass ( M ⋆ ), disk mass ( M disk ), CO and dust sizes ( R CO , R dust ), and mass accretion of the entire population. We searched for correlations between the size ratio and M ⋆ , M disk , R CO , and R dust : only a weak monotonic anticorrelation with the R dust is found, which would imply that dust evolution is more prominent in more compact dusty disks. The lack of strong correlations is remarkable: the sample covers a wide range of stellar and disk properties, and the majority of the disks have very similar size ratios. This result suggests that the bulk of the disk population may behave alike and be in a similar evolutionary stage, independent of the stellar and disk properties. These results should be further investigated, since the optical depth difference between CO and dust continuum might play a major role in the observed size ratios of the population. Lastly, we find a monotonic correlation between the CO flux and the CO size. The results for the majority of the disks are consistent with optically thick emission and an average CO temperature of around 30 K; however, the exact value of the temperature is difficult to constrain. 

Summary The majority of plant colours are produced by anthocyanin and carotenoid pigments, but colouration obtained by nanostructured materials (i.e. structural colours) is increasingly reported in plants. Here, we identify a multilayer photonic structure in the fruits ofLantana strigocamaraand compare it with a similar structure inViburnum tinusfruits.We used a combination of transmission electron microscopy (EM), serial EM tomography, scanning force microscopy and optical simulations to characterise the photonic structure inL. strigocamara. We also examine the development of the structure during maturation.We found that the structural colour derives from a disordered, multilayered reflector consisting of lipid droplets ofc.105 nm that form a plate‐like structure in 3D. This structure begins to form early in development and reflects blue wavelengths of light with increasing intensity over time as the structure develops. The materials used are likely to be lipid polymers.Lantana strigocamarais the second origin of a lipid‐based photonic structure, convergently evolved with the structure inViburnum tinus. Chemical differences between the lipids inL. strigocamaraand those ofV. tinussuggest a distinct evolutionary trajectory with implications for the signalling function of structural colours in fruits. 

Abstract The colours of fleshy fruits play a critical role in plant dispersal by advertising ripe fruits to consumers. Fruit colours have long been classified into syndromes attributed to selection by animal dispersers, despite weak evidence for this hypothesis. Here, we test the relative importance of biotic (bird and mammal frugivory) and abiotic (wet season temperatures, growing season length and UV‐B radiation) factors in determining fruit colour syndrome in 3163 species of fleshy‐fruited plants. We find that both dispersers and environment are important, and they interact. In warm areas, contrastive, bird‐associated fruit colours increase withrelative bird frugivore prevalence, whereas in cold places these colours dominate even where mammalian dispersers are prevalent. We present near‐global maps of predicted fruit colour syndrome based on our species‐level model and our newly developed characterisations of relative importance of bird and mammal frugivores. 

We present new 890 μ m continuum ALMA observations of five brown dwarfs (BDs) with infrared excess in Lupus I and III, which in combination with four previously observed BDs allowed us to study the millimeter properties of the full known BD disk population of one star-forming region. Emission is detected in five out of the nine BD disks. Dust disk mass, brightness profiles, and characteristic sizes of the BD population are inferred from continuum flux and modeling of the observations. Only one source is marginally resolved, allowing for the determination of its disk characteristic size. We conduct a demographic comparison between the properties of disks around BDs and stars in Lupus. Due to the small sample size, we cannot confirm or disprove a drop in the disk mass over stellar mass ratio for BDs, as suggested for Ophiuchus. Nevertheless, we find that all detected BD disks have an estimated dust mass between 0.2 and 3.2 M ⊙ ; these results suggest that the measured solid masses in BD disks cannot explain the observed exoplanet population, analogous to earlier findings on disks around more massive stars. Combined with the low estimated accretion rates, and assuming that the mm-continuum emission is a reliable proxy for the total disk mass, we derive ratios of Ṁ acc ∕ M disk that are significantly lower than in disks around more massive stars. If confirmed with more accurate measurements of disk gas masses, this result could imply a qualitatively different relationship between disk masses and inward gas transport in BD disks.