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Ecological traits have flourished in insect-based studies, resulting in a substantial and growing list of measurable traits. One trait that will likely become more attractive as data quality and curation improve is the diel patterns of insect activities. Diel patterns in ants can help better understand vital ecological processes such as competition and invasion biology. Because diel activity has the potential to be an informative trait in ants, we assessed the diel designations of foraging ants across the literature to quantify and assess the variation and sampling extent of this particular trait. We collected diel designations from 104 peer-reviewed scientific articles and quantified these data across important and documented ecological traits. We found that a disproportionate amount of solitary foraging ants were primarily diurnal foragers relative to ants that cooperatively forage. Our data show that diel patterns in foraging vary widely within and across ant genera. Importantly, we highlight the undersampling of this crucial ecological trait, which currently limits its utility. Our efforts highlight the importance of assessing an ecologically important trait’s landscape of reported data. 

In 1901, Forel described an ant species from a relatively poorly known genus of ants from North America, naming it Strumigenys pilinasis. In 1931 M. R. Smith obtained the holotype and redescribed it, and he included a first illustration. The description was incomplete and the illustration resembled Strumigenys brevisetosa Smith, 1935, more than it resembled S. pilinasis, which led subsequent taxonomists to make consistent misidentifications and to consider S. brevisetosa to be a synonym of S. pilinasis. Here I redescribe both S. pilinasis and S. brevisetosa (revived status). Strumigenys manni Wesson & Wesson, 1939, and S. ohioensis Kennedy & Schramm, 1933, are new junior synonyms of S. pilinasis, and S medialis Kennedy & Schramm, 1933, is a new junior synonym of S. brevisetosa. 

In this study, we revise two groups of cryptic leaf litter ants, the Strumigenys nitens and Strumigenys simulans species groups. These two groups are restricted to the Greater Antilles and the Bahamas. We redefine the species groups, provide a key for the five species in the S. nitens group, and differentiate the two species in the S. simulans group. Four new species are described: Strumigenys caiman sp. nov., S. economoi sp. nov., S. hubbewatyorum sp. nov., and S. zemi sp. nov. We review and provide a key for the Strumigenys fauna of Hispaniola, which comprises the two endemic species S. economoi and S. zemi, six more broadly distributed Neotropical species, and three pan-tropical “tramp” species. 

Evolutionary innovations underlie the rise of diversity and complexity—the 2 long-term trends in the history of life. How does natural selection redesign multiple interacting parts to achieve a new emergent function? We investigated the evolution of a biomechanical innovation, the latch-spring mechanism of trap-jaw ants, to address 2 outstanding evolutionary problems: how form and function change in a system during the evolution of new complex traits, and whether such innovations and the diversity they beget are repeatable in time and space. Using a new phylogenetic reconstruction of 470 species, and X-ray microtomography and high-speed videography of representative taxa, we found the trap-jaw mechanism evolved independently 7 to 10 times in a single ant genus ( Strumigenys ), resulting in the repeated evolution of diverse forms on different continents. The trap mechanism facilitates a 6 to 7 order of magnitude greater mandible acceleration relative to simpler ancestors, currently the fastest recorded acceleration of a resettable animal movement. We found that most morphological diversification occurred after evolution of latch-spring mechanisms, which evolved via minor realignments of mouthpart structures. This finding, whereby incremental changes in form lead to a change of function, followed by large morphological reorganization around the new function, provides a model for understanding the evolution of complex biomechanical traits, as well as insights into why such innovations often happen repeatedly. 

Abstract Dated, geo‐referenced museum specimens are a rich data source for reconstructing species' distribution and abundance patterns. However, museum records are potentially biased towards over‐representation of rare species, and it is unclear whether museum records can be used to estimate relative abundance in the field.We assembled 17 coupled field and museum datasets to quantitatively compare relative abundance estimates with the Dirichlet distribution. Collectively, these datasets comprise 73,039 museum records and 1,405,316 field observations of 2,240 species.Although museum records of rare species overestimated relative abundance by 1‐fold to over 100‐fold (median study = 9.0), the relative abundance of species estimated from museum occurrence records was strongly correlated with relative abundance estimated from standardized field surveys (r²range of 0.10–0.91, median study = 0.43).These analyses provide a justification for estimating species relative abundance with carefully curated museum occurrence records, which may allow for the detection of temporal or spatial shifts in the rank ordering of common and rare species.