The evolution of modern human life history has involved substantial changes in the overall length of the subadult period, the introduction of a novel early childhood stage, and many changes in the initiation, termination, and character of the other stages. The fossil record is explored for evidence of this evolutionary process, with a special emphasis on middle childhood, which many argue is equivalent to the juvenile stage of African apes. Although the "juvenile" and "middle childhood" stages appear to be the same from a broad comparative perspective, in that they begin with the eruption of the first molar and the achievement of the majority of adult brain size and end with sexual maturity, the detailed differences in the expression of these two stages, and how they relate to the preceding and following stages, suggest that a distinction should be maintained between them to avoid blurring subtle, but important, differences.

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Once abundant and widely distributed, the Bahama parrot (Amazona leucocephala bahamensis) currently inhabits only the Great Abaco and Great Inagua Islands of the Bahamas. In January 2003 and May 2002–2004, we conducted point‐transect surveys (a type of distance sampling) to estimate density and population size and make recommendations for monitoring trends. Density ranged from 0.061 (SE = 0.013) to 0.085 (SE = 0.018) parrots/ha and population size ranged from 1,600 (SE = 354) to 2,386 (SE = 508) parrots when extrapolated to the 26,154 ha and 28,162 ha covered by surveys on Abaco in May 2002 and 2003, respectively. Density was 0.183 (SE = 0.049) and 0.153 (SE = 0.042) parrots/ha and population size was 5,344 (SE = 1,431) and 4,450 (SE = 1,435) parrots when extrapolated to the 29,174 ha covered by surveys on Inagua in May 2003 and 2004, respectively. Because parrot distribution was clumped, we would need to survey 213–882 points on Abaco and 258‐1,659 points on Inagua to obtain a CV of 10–20% for estimated density. Cluster size and its variability and clumping increased in wintertime, making surveys imprecise and cost‐ineffective. Surveys were reasonably precise and cost‐effective in springtime, and we recommend conducting them when parrots are pairing and selecting nesting sites. Survey data should be collected yearly as part of an integrated monitoring strategy to estimate density and other key demographic parameters and improve our understanding of the ecological dynamics of these geographically isolated parrot populations at risk of extinction.

Urban patch colonization and species establishment within cities are restricted by the behavioural, life history and physiological attributes of colonizing species, in conjunction with environmental filtering processes at small and large spatial scales. To enhance the local biodiversity in urban greenspaces, these filtering processes need to be assessed so that greenspace design and management can guide establishment of local species pools. We investigated the relative importance of local and landscape‐scale features on spider community assembly using a functional and taxonomic approach. Within the city of Cleveland, Ohio, USA, we established a field experiment wherein control vacant lots, urban meadows, and low‐ and high‐diversity pocket prairies were established across eight neighbourhoods (N = 32). Spiders were sampled during June–August of 2015 and 2016 using pitfall traps and vacuums. Spider functional diversity was assessed using null models, while local and landscape drivers were analysed via canonical partial least squares and clustered image maps. Increased mowing was associated with lower‐than‐expected spider functional alpha and beta diversity in 2015. Patch isolation and percentage impervious surface increased the functional dissimilarity and taxonomic diversity of spiders in 2016, resulting in higher‐than‐expected overall functional alpha diversity. We also found that increasing plant height and biomass favoured spiders with large body size and decreased the abundance of small web weavers. Synthesis and applications. Our findings suggest that increasing the amount of impervious surface in cities will act as a strong environmental filter, producing more spatially distinct spider communities at a landscape scale. Additionally, while periodic mowing in vacant lots benefits some spider taxa, it has a negative impact on the establishment of several species, mainly larger spiders and those most sensitive to disturbance. To conserve spiders and the biota depended upon them, investment in managed greenspaces such as pocket prairies that require infrequent mowing is warranted. In doing so, cities can enhance urban biodiversity and beautify local neighbourhoods.