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The Great American Biotic Interchange (GABI) was a key biogeographic event in the history of the Americas. The rising of the Panamanian land bridge ended the isolation of South America and ushered in a period of dispersal, mass extinction, and new community assemblages, which sparked competition, adaptation, and speciation. Diversification across many bird groups, and the elevational zonation of others, ties back to events triggered by the GABI. But the exact timing of these events is still being revealed, with recent studies suggesting a much earlier time window for faunal exchange, perhaps as early as 20 million years ago (Mya). Using a time‐calibrated phylogenetic tree, we show that the jay genus Cyanolyca is emblematic of bird dispersal trends, with an early, pre‐land bridge dispersal from Mesoamerica to South America 6.3–7.3 Mya, followed by a back‐colonization of C. cucullata to Mesoamerica 2.3–4.8 Mya, likely after the land bridge was complete. As Cyanolyca species came into contact in Mesoamerica, they avoided competition due to a prior shift to lower elevation in the ancestor of C. cucullata. This shift allowed C. cucullata to integrate itself into the Mesoamerican highland avifauna, which our time‐calibrated phylogeny suggests was already populated by higher‐elevation, congeneric dwarf‐jays (C. argentigula, C. pumilo, C. mirabilis, and C. nanus). The outcome of these events and fortuitous elevational zonation was that C. cucullata could continue colonizing new highland areas farther north during the Pleistocene. Resultingly, four C. cucullata lineages became isolated in allopatric, highland regions from Panama to Mexico, diverging in genetics, morphology, plumage, and vocalizations. At least two of these lineages are best described as species (C. mitrata and C. cucullata). Continued study will further document the influence of the GABI and help clarify how dispersal and vicariance shaped modern‐day species assemblages in the Americas. [ABSTRACT FROM AUTHOR]

Objective: Cognitive appraisals, that is, interpretations of what is observed and the personal relevance attributed to those observations, affect one's behavior and well-being. Despite the centrality of appraisals in the transactional model of stress and coping, the application of spinal cord injury (SCI)-specific appraisals to adjustment is a recent development. This study examined the psychometric properties of a measure of SCI-specific appraisals, the Appraisals of DisAbility Primary and Secondary Scale--Short Form (ADAPSS-sf). Method: A retrospective study using clinical data from SCI annual evaluations at a U.S. Department of Veterans Affairs medical center was employed (N = 262). Results: Findings supported the ADAPSS-sf's 2-factor structure of catastrophic negativity and determined resilience. SCI appraisals were associated with mental health concerns, mental disorders, life satisfaction, racial minority status, age, SCI severity (based on the American Spinal Injury Association Impairment Scale [AIS]), and SCI etiology (traumatic or nontraumatic). Counterintuitively, those with less severe injuries (i.e., AIS D) had the greatest catastrophic negativity. Although veterans with SCI were heterogeneous in their appraisals, it is encouraging that they tended to endorse determined resilience and disavow catastrophic negativity. Conclusions: The ADAPSS-sf demonstrated many desirable characteristics, including brevity, convergent validity, and face-valid content. An implication of this study is that to understand the adjustment experience, one must look beyond injury severity and impairment to the individual's personal and subjective experience of SCI. The ADAPSS-sf offers clinicians and researchers a potentially valuable tool to assess SCI appraisals and personalize treatment. [ABSTRACT FROM AUTHOR]