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In order to deal with a complex environment, animals form a diverse range of neural representations that vary across cortical areas, ranging from largely unimodal sensory input to higher-order representations of goals, outcomes, and motivation. The developmental origin of this diversity is currently unclear, as representations could arise through processes that are already area-specific from the earliest developmental stages or alternatively, they could emerge from an initially common functional organization shared across areas. Here, we use spontaneous activity recorded with two-photon and widefield calcium imaging to reveal the functional organization across the early developing cortex in ferrets, a species with a well-characterized columnar organization and modular structure of spontaneous activity in the visual cortex. We find that in animals 7 to 14 d prior to eye-opening and ear canal opening, spontaneous activity in both sensory areas (auditory and somatosensory cortex, A1 and S1, respectively), and association areas (posterior parietal and prefrontal cortex, PPC and PFC, respectively) showed an organized and modular structure that is highly similar to the organization in V1. In all cortical areas, this modular activity was distributed across the cortical surface, forming functional networks that exhibit millimeter-scale correlations. Moreover, this modular structure was evident in highly coherent spontaneous activity at the cellular level, with strong correlations among local populations of neurons apparent in all cortical areas examined. Together, our results demonstrate a common distributed and modular organization across the cortex during early development, suggesting that diverse cortical representations develop initially according to similar design principles. 

Using the pollen loads carried by floral visitors to infer their floral visitation behavior is a powerful technique to explore the foraging of wild pollinators. Interpreting these pollen records, however, requires assumptions about the underlying pollen dynamics. To compare visitor foraging across flower species, the most important assumption is that pollen is picked up and retained on the visitor at similar rates. Given differences in pollen presentation traits such as grain number or stickiness even among flowers with similar morphologies, however, the generality of this assumption is unclear. We investigated pollen accumulation on the hawkmoth Manduca sexta, testing the degree to which accumulation differed among flower species and how pollen stickiness affected this accumulation. In no-choice floral visitation assays to six plant species visited by long-tongued hawkmoths in the wild, M. sexta individuals were allowed to visit flowers 1, 2, or 5 times, after which the pollen on their proboscises was removed and counted.  We found that the six plant species varied orders of magnitude in the number of pollen grains deposited on the moths, with some placing thousands of grains after a single visit and other placing none after five. Plant species with sticky pollen adhesion mechanisms placed more pollen on the moths and had relatively less pollen accumulation over successive visits than non-sticky plants. Intriguingly, moths carried fewer pollen grains after 5 visits than after 2 visits, suggesting that both sticky and non-sticky pollen was lost during foraging. Together, our results suggest that interpretation of pollen load data should be made cautiously, especially when comparing across plant species. 

1. Precise pollen placement on floral visitors can improve pollen transfer, but in many plant species, pollen is deposited onto the flexible proboscises of long-tongued insects. These proboscises are curled and uncurled between floral visits, potentially causing pollen to be lost or displaced. Rates of pollen movement and loss resulting from proboscis curling, and hence the potential quality of long-tongued insects as pollinators, are unknown. 2. Here, pollen loss and movement on the proboscises of Manduca sexta (Sphingidae) hawkmoths was experimentally measured. It was predicted that (i) proboscis curling causes pollen loss; (ii) pollen that is not lost is displaced from its deposition site; and (iii) repeated curls result in more displacement. Pollen from Datura wrightii, an important nectar plant for M. sexta, was placed distal to the knee bend on M. sexta proboscises, and the number and location of grains was recorded after proboscis curls. 3. Consistent with the hypotheses, proboscis curling caused significant pollen loss. (i) A single curl resulted in the loss of almost 75% of the pollen from the placement site; after repeated curling, 98% of grains were lost from this site. (ii) A single curl was also sufficient to displace pollen across all surfaces of the proboscis, but (iii) further curling did not affect its distribution across surfaces. 4. Together, these results suggest that precise pollen placement on the proboscises of hawkmoths would be unlikely to increase pollen transfer success. Strategies by which flowering plants might mitigate the effects of pollen loss from visitors with flexible pollen-pickup structures are discussed. 

Abstract Sex‐associated differences in behavior can have large ecological consequences, especially in plant–pollinator communities where floral visitor behavior affects plant reproduction. Whether these differences are prevalent enough to impact community‐level processes, however, is unknown. Using 256 plant–pollinator communities, we built networks where the floral interactions of each sex were modeled separately, comparing observations to simulated networks where sex was randomized. We found that (1) in many species the sexes differed in their network roles and visited different partners, with females tending to visit more species and more peripheral species than males; (2) more generalist species differed more in network roles between the sexes; and (3) networks where nodes were separated by sex were more specialized than simulated networks, but were similarly resistant to perturbations. These findings suggest that despite variation among species, sex‐associated differences in behavior are large enough to impact the network roles of male and female pollinators and common enough to influence the interaction patterns of entire plant–pollinator communities.