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Documents and correspondence documenting the ornithology research of Amos W. Butler, specifically Butler's travels and birdwatching throughout Mexico in the winter of 1879-1880. It includes his notes on the migration patterns for birds throughout Indiana (mainly Brookville), Latin names of birds, and general observations about the birds, as well as the correspondence from notable names in natural science such as Prof. John James Bowrey, Robert Service, and Prof. Edwin Rockstroh, in which they discussed exchanges of specimens distinct to their locations and possible trades between them for further examination.

The integration of deep learning and theories of reinforcement learning (RL) is a promising avenue to explore novel hypotheses on reward-based learning and decision-making in humans and other animals. Here, we trained deep RL agents and mice in the same sensorimotor task with high-dimensional state and action space and studied representation learning in their respective neural networks. Evaluation of thousands of neural network models with extensive hyperparameter search revealed that learning-dependent enrichment of state-value and policy representations of the task-performance-optimized deep RL agent closely resembled neural activity of the posterior parietal cortex (PPC). These representations were critical for the task performance in both systems. PPC neurons also exhibited representations of the internally defined subgoal, a feature of deep RL algorithms postulated to improve sample efficiency. Such striking resemblance between the artificial and biological networks and their functional convergence in sensorimotor integration offers new opportunities to better understand respective intelligent systems. Ministry of Education (MOE) Nanyang Technological University Published version This work was supported by the NARSAD Young Investigator Grant, the Brain & Behavior Research Foundation (to H.M.); Nanyang Assistant Professorship, Nanyang Technological University (to H.M.); Singapore Ministry of Education Academic Research Fund Tier 1 2018-T1-001-032 (to H.M.); Singapore Ministry of Education Academic Research Fund Tier 1 RT11/19 (to H.M.); Singapore Ministry of Education Academic Research Fund Tier 2 MOE2018-T2-1-021 (to H.M.); and Singapore Ministry of Education Academic Research Fund Tier 3 MOE2017-T3-1-002 (to H.M.)

© 2020 The Authors. Ectomycorrhizal fungi are key players in terrestrial ecosystems yet their mating systems and population dynamics remain poorly understood. We investigated the fine-scale relatedness structure and genetic diversity of Boletus edulis, one of the world's most commercially important wild mushrooms. Microsatellite genotyping of fruiting bodies from 14 different sites around Bielefeld in Germany revealed little in the way of population structure over a geographic scale of several kilometres. However, on a more local scale we found evidence for elevated relatedness as well as inbreeding. We also observed a significant negative association between the genetic diversity of fruit and the age of the trees under which they were sampled. Taken together, our results suggest that as genets mature, they compete and potentially create conditions under which further spores struggle to become established. By implication, even though this species is widely picked, propagules remain common enough to create strong competition when new habitats become available.

Declining soil fertility continues to hinder agricultural production especially among resource-constrained smallholder farmers in sub-Saharan Africa, prompting for evaluation of the strategies used by these farming communities. In this study, we assess soil fertility management among smallholder farmers in Mount Kenya East region. The aim is to examine underlying factors conditioning the uptake of integrated soil fertility management (ISFM) practices in this region; determine the adoption relationship between the practices; and to cluster these techniques. Data for this study was collected between January–March 2019 through a household survey based on a farm household questionnaire and complemented with semi-structured interview with farmers and extension officers. Statistical analyses were generated using SPSS. We use hierarchical clustering analysis to visualize ISFM combination patterns, and correlation matrix in factor analysis to determine the inter-relationship between different ISFM practices. Fisher's exact test and Welch's t-test were used to examine the association between explanatory variables and adoption of ISFM practices. Results show that the decision to invest in fertility practices was correlated with a number of farmers' socio-economic, farm-related factors and institutional characteristics. Fertilizer application correlated significantly with manure use, agroforestry and minimum tillage. ISFM techniques were separated into 3 sets following Ward's hierarchical clustering, namely, manure, fertilizer use and agroforestry (cluster 1 or C1), slash-no-burn, residue burn and fallowing (C2); and residue application and minimum tillage (C3). The study recommends creation of an enabling environment including innovative financing opportunities to facilitate farmers' investment capacities in ISFM and cushion them from potential income loss resulting from implementation of some technologies., Soil fertility; Technology clusters; Integrated soil fertility management (ISFM); Fertilizer; Manure; Agricultural technology adoption; Kenya; Sub-Saharan Africa.

© 2020 The Authors. Non-African humans appear to carry a few per cent archaic DNA due to ancient inter-breeding. This modest legacy and its likely recent timing imply that most introgressed fragments will be rare and hence will occur mainly in the heterozygous state. I tested this prediction by calculating D statistics, a measure of legacy size, for pairs of humans where one of the pair was conditioned always to be either homozygous or heterozygous. Using coalescent simulations, I confirmed that conditioning the non-African to be heterozygous increased D, while conditioning the non-African to be homozygous reduced D to zero. Repeating with real data reveals the exact opposite pattern. In African-non-African comparisons, D is near-zero if the African individual is held homozygous. Conditioning one of two Africans to be either homozygous or heterozygous invariably generates large values of D, even when both individuals are drawn from the same population. Invariably, the African with more heterozygous sites (conditioned heterozygous > unconditioned > conditioned homozygous) appears less related to the archaic. By contrast, the same analysis applied to pairs of non-Africans always yields near-zero D, showing that conditioning does not create large D without an underlying signal to expose. Large D values in humans are therefore driven almost entirely by heterozygous sites in Africans acting to increase divergence from related taxa such as Neanderthals. In comparison with heterozygous Africans, individuals that lack African heterozygous sites, whether non-African or conditioned homozygous African, always appear more similar to archaic outgroups, a signal previously interpreted as evidence for introgression. I hope these analyses will encourage others to consider increased divergence as well as increased similarity to archaics as mechanisms capable of driving asymmetrical base-sharing.

Code used to analyse the data and accompanying documentation