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Abstract Understanding biodiversity is critical for the proper conservation of ecosystems experiencing extreme stress from global change. Few other ecosystems are at such high risk of disappearing, especially due to logging and agricultural activities, as the Massif de la Hotte, a chain of mountains in Haiti on the island of Hispaniola, located within the Caribbean Biodiversity Hotspot. We used the hyperdiverse tropical plant family Melastomataceae to understand the biogeographical history and endemism patterns in a major hotspot for the family, the Massif de la Hotte, Haiti. Our goal was to determine the number, timing, and geographical origin of introductions of Melastomataceae (particularly Miconieae) into the Massif de la Hotte. We also aimed to identify whether the Massif de la Hotte and neighbouring ranges on Hispaniola and Cuba were so-called museums or cradles of biodiversity, and determine the extent that areas of high diversity and endemism overlap with currently conserved lands. In total, our analyses uncovered 19 independent dispersal events of Miconieae to the Massif de la Hotte. The Mecranium, Brevycima, and Meriania clades all had rapid radiations consisting of narrow endemics inferred to be of Massif de la Hotte origin. Species of the Chaenopleura clade in the Massif de la Hotte were mostly products of solitary dispersal events from eastern Cuba or the Massif de la Selle. The Massif de la Hotte endemics in the Caribbean Clade were largely the result of dispersal events from central and eastern Cuba. Eastern Cuba is also inferred as the ancestral area for many Massif de la Hotte endemic clades. A total of 25 10 × 10-km grid cells were found by CANAPE to contain significant endemism, with a high proportion of endemism hotspots over the Massif de la Hotte and eastern Cuba. Overlap of these significant CANAPE cells with currently protected areas was high (∼90%). Elucidating phylogenetic diversity and endemism patterns across the vastly different ecosystems of this biodiversity hotspot will aid in our understanding of how these biodiverse forests were formed. 

The positive benefits of fostering a Growth Mindset in students have been widely reported. Developing the skill of persisting through and learning from failure is key to developing a growth mindset and the entrepreneurial mindset – KEEN (Kern Entrepreneurial Engineering Network). This work-in-progress paper will examine how an MBL model could be a valuable tool for developing our students’ Failure Mindset. The MBL framework we employ is centered on learning through practice and coaching – making mistakes and learning from those mistakes, frequent low-stakes assessments, analyzing the results for further practice, and coaching on that skill or before moving forward to the next skill. A positive Failure Mindset looks at failure as a positive outcome that enhances one’s opportunities for learning. In this study, we will explore preliminary data by examining three groups of students: • entering first-year students, including those enrolled in an MBL course and those not enrolled in this course, • third-year students enrolled in an MBL course – 90% of these students have previously taken at least one MBL course, • and students enrolled in a one-semester off-campus alternative MBL-assessed project-based learning curriculum. We will use an established tool for assessing Failure Mindset and test the following hypotheses. • H1 – At initial assessment, students in 3rd-year students will exhibit a higher propensity toward a positive Failure Mindset than the entering first-year students. • H2 – The measure of Failure Mindset will increase over the course of the semester for all 3 groups of students. • H3 – the 1st year students in the MBL course will exhibit a more positive failure mindset at the end of the semester than those not enrolled in an MBL course. 

Understanding the causes of subsistence economic adaptation remains a critical topic in archaeology. Here we explore one potential causal phenomenon, climate change, to understand how shifting ecological conditions incentivized adaptation through subsistence economic intensification along the Central Andean coasts. To do so we couple 775 archaeological individuals that have dietary stable isotope data (collagen δ13C and δ15N, hydroxyapatite δ13C) with spatio-temporal core-based proxies of oceanic sea surface temperature and El Ni˜no Southern Oscillation frequency estimates. Using an ensemble machine learning model, we evaluate hypotheses that changes in ocean conditions resulting in decreased marine productivity correspond with isotopic signals of increasing terrestrial resource reliance over the past ~7000 years. Results support the hypotheses, and prior work, showing isotopic signatures of diet across the coastal Central Andes reflect greater incorporation of resources indicative of intensification during times when marine productivity was likely depressed. As near-shore marine productivity declined, people adapted in manners that may have both increased their resiliency to climate change and improved their overall subsistence returns, but at higher investment costs. The overall findings support theoretical intensification expectations, suggesting adaptation through intensification represents one of the key factors in understanding broader behavioral transformation in the face of climate change. 

Past population change is connected to significant shifts in human behavior and experience including landscape manipulation, subsistence change, sedentism, technological change, material inequality and more. However, population change appears to result from a complex interplay of human-environment interactions that feedback on each other, influencing and simultaneously impacted by processes such as subsistence intensification and climate change. Here we explore complex system dynamics of population change using theoretical and Approximate Bayesian Computational modeling combined with the archaeological record of the past 4,000 years in the Colorado Plateau and Great Basin regions of western North America as case studies to identify causal relationships and the different manners in which climate change may have interplayed with subsistence economic intensification and population dynamics. Using standard distance metric evaluation on the performance of 1,000,000 simulations compared with reconstructed past population sizes in each region reveals how climate change impacting landscape productivity can influence carrying capacity and structure population growth such that, when populations reach carrying capacity (Malthusian ceilings), intensification in their subsistence economy can send feedbacks into the socioecological system spurring rapid, differential, population growth. Comparisons of the two regions highlights how varied socioecological circumstances can produce alternative pathways to, and limitations on, population expansions. 

Abstract—The diverse and spectacular Hibisceae tribe comprises over 750 species. No studies, however, have broadly sampled across the dozens of genera in the tribe, leading to uncertainty in the relationships among genera. The non-monophyly of the genusHibiscusis infamous and challenging, whereas the monophyly of most other genera in the tribe has yet to be assessed, including the large genusPavonia.Here we significantly increase taxon sampling in the most complete phylogenetic study of the tribe to date. We assess monophyly of most currently recognized genera in the tribe and include three and thirteen newly sampled sections ofHibiscusandPavonia,respectively. We also include five rarely sampled genera and 137 species previously unsampled. Our phylogenetic trees demonstrate thatHibiscus, as traditionally defined, encompasses at least 20 additional genera. The status ofPavoniaemerges as comparable in complexity toHibiscus. We offer clarity in the phylogenetic placement of several taxa of uncertain affinity (e.g.Helicteropsis,Hibiscadelphus, Jumelleanthus,andWercklea). We also identify two new clades and elevate them to the generic rank with the recognition of two new monospecific genera: 1)BlanchardiaM.M.Hanes & R.L.Barrett is a surprising Caribbean lineage that is sister to the entire tribe, and 2)AstrohibiscusMcLay & R.L.Barrett represents former members ofHibiscus caesiuss.l.CraveniaMcLay & R.L.Barrett is also described as a new genus for theHibiscus panduriformisclade, which is allied toAbelmoschus. Finally, we introduce a new classification for the tribe and clarify the boundaries ofHibiscusandPavonia. 

Understanding how resource characteristics influence variability in social and material inequality among foraging populations is a prominent area of research. However, obtaining cross-comparative data from which to evaluate theoretically informed resource characteristic factors has proved difficult, particularly for investigating interactions of characteristics. Therefore, we develop an agent-based model to evaluate how five key characteristics of primary resources (predictability, heterogeneity, abundance, economy of scale and monopolizability) structure pay-offs and explore how they interact to favour both egalitarianism and inequality. Using iterated simulations from 243 unique combinations of resource characteristics analysed with an ensemble machine-learning approach, we find the predictability and heterogeneity of key resources have the greatest influence on selection for egalitarian and nonegalitarian outcomes. These results help explain the prevalence of egalitarianism among foraging populations, as many groups probably relied on resources that were both relatively less predictable and more homogeneously distributed. The results also help explain rare forager inequality, as comparison with ethnographic and archaeological examples suggests the instances of inequality track strongly with reliance on resources that were predictable and heterogeneously distributed. Future work quantifying comparable measures of these two variables, in particular, may be able to identify additional instances of forager inequality. This article is part of the theme issue ‘Evolutionary ecology of inequality’.