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In the archaeological literature, mountains are often portrayed as the boundaries between inhabited spaces. Yet occupying high elevations may have been an adaptive choice for ancient peoples, as rapidly changing elevations also offer variation in climate and resources over a relatively small area. So what happens, instead, if we put mountain landscapes at the center of our analyses of prehistoric seasonal rounds and ecological adaptation? This Ph.D. argues that, in order to understand any landscape that includes mountains, from the Alps to the Andes, one must include the ecology and archaeology of the highest elevations. Specifically, I base my findings on new fieldwork and lithic collections from the Absaroka and Beartooth Mountains in the Greater Yellowstone Ecosystem (GYE) of the Rocky Mountains, which was a vital crossroads of prehistoric cultures for more than 11,000 years. I include five interlocking analyses. First, I consider the impacts of anthropogenic climate change on high elevation cultural resources, focusing on the diminishing resiliency of ancient high elevation ice patches and the loss of the organic artifacts and paleobiological materials they contain. Second, I create a dichotomous key for chronologically typing projectile points, suggesting a methodological improvement for typological dating in the GYE and for surface archaeology more broadly. Third, I use obsidian source data to consider whether mountain people were a single, unified group or were represented by a variety of peoples with different zones of land tenure. Fourth, I consider high elevation occupation in both mountain ranges as part of the seasonal round, using indices of diversity in tool types and raw material to study how the duration of those occupations changed through time. And, finally, I test the common contention that ancient people primarily used mountains as refugia from extreme climatic pressure at lower elevations. Ultimately, I find that, in both mountain ranges, increased high elevation activity is most highly correlated with increased population, not with hot, dry climatic conditions. In other words, the mountains were more than simply refugia for plains or basin people to occupy when pressured by climatic hardship. In addition, between the Absarokas and the Beartooths the evidence suggests two different patterns of occupation, not a monolithic pan-mountain adaptation. These results demonstrate the potential contributions of surface archaeology to our understanding of prehistory, and have important implications for the way we think about mountain landscapes as peopled spaces in relation to adjacent lower-elevation areas.

The Tigris and Euphrates Rivers and their tributaries form the arteries of life in the central part of the Middle East, where climate change and anthropogenic disturbance have been evident in recent decades. While the Tigris River has a long history of human use, the conservation status for the majority of its basin is poorly known. In addition, planning for conservation, given limited time, funds, and prior information, has remained a challenge. In my dissertation research, I sampled 53 randomly selected sites in the Kurdistan Region (the KR) of northern Iraq, a poorly studied region of the Upper Tigris and Euphrates freshwater ecoregion, for water quality bioindicators, mayflies (Insecta, Ephemeroptera), stoneflies (Plecoptera), and caddisflies (Trichoptera) (a.k.a. EPT). I identified the mayflies to the finest possible taxonomic level and created the first Iraqi checklist and larval key to nine families, nine subfamilies, 19 genera, and 13 subgenera, and supported it with 117 state-of-the-art scientific illustrations using fresh specimens collected during my study (Chapter 1). I performed an initial species morphological identification for mayflies and stoneflies, then identified them genetically after sequencing the full-length of the mitochondrial cytochrome oxidase subunit 1 (COI) gene (658 base pairs). I introduced Genetic Similarity Blocks (GSBs), a genetic-based analysis which was used along with morphology and other genetic-based analyses to overcome the taxonomic impediment and accelerate species identification. I delineated Operational Taxonomic Units (OTUs) using genetic-based analyses, then matched OTUs to delineate Species-Like Units (SpLUs). I compared and contrasted SpLUs morphologically and found five stonefly and more than 55 mayfly taxa, the majority of them being new records for Iraq, and many of them potentially new to science (Chapter 2). I identified 76 planning units within aquatic ecosystems in the KR and prioritized a subset of them for EPT conservation using my mayfly and stonefly data as well as caddisfly data from other studies. I identified samples of healthy aquatic habitats from this subset and used them along with various predictor variables to predict the distribution of healthy aquatic habitats across the entire KR. I identified one natural lake and 23 stream segments as habitats of conservation priority in the KR (Chapter 3). In my dissertation, I showed that in developing countries where knowledge about aquatic ecosystems and most extant species is unavailable, conservation priorities can still be identified after rapid assessment for water quality bioindicators.

Select freshwater mussels in the genera Fusconaia, Pleurobema, and Pleuronaia were collected primarily in the upper Tennessee River basin from 2012 to 2014 for phylogenetic and morphological assessments. Freshwater mussels in these genera are similar in appearance, hence the need for phylogenetic verification and morphological assessment. Phylogenetic analyses of the mitochondrial gene ND1 and the nuclear gene ITS1 revealed three unrecognized, phylogenetically distinct species. These species were separated from their closest congener by 2.85%, 3.17%, and 6.32% based on pairwise genetic distances of ND1. Gaps created from aligning ITS1 sequences were coded as fifth characters, which phylogenetically separated most closely related species. Analyses of ND1 agreed with previous literature on the phylogenetic distinctiveness of Pleuronaia species, with the exception of the DNA sequences of P. gibberum, which grouped outside this genus based on the analyses conducted in this study. Morphological variation was recorded for eight of the species to include quantitative and qualitative characters as well as geometric morphometric analyses. Three decision trees were created from quantitative and qualitative characters using classification and regression tree analyses. The best-performing tree used quantitative and qualitative characters describing shell-only scenarios and obtained 80.6% correct classification on terminal nodes. Canonical variates analysis on geometric morphometric shell data revealed large morphological overlap between species. Goodall's F-tests between pairs of species revealed significant differences (a=0.05) between all but one species pairs; however, examination of landmarks on shells concluded large overlap of landmarks between species pairs. Lack of morphologically distinct characters to readily identify these phylogenetically distinct species indicates large morphological overlap among these species. Biologists need to be cognizant that morphologically cryptic species may exist in systems often explored. Three dichotomous keys were created from classification trees to identify select individuals in the genera Fusconaia, Pleurobema, and Pleuronaia; two of these keys, one for shells and one for live mussels were tested by participants with varying mussel identification skills to represent novices and experts. Both keys used continuous (quantitative) and categorical variables to guide participants to identifications. Novices, who had no prior mussel identification experience, correctly identified mussels with a 50% accuracy using the shell key and with a 51% accuracy using the live key. Experts, who had at least three years of experience identifying mussels, correctly identified mussels with a 58% accuracy using the shell key and with a 68% accuracy using the live key; however one expert noted that they did not use the live key to correctly identify one mussel. Morphological overlap of variables between mussels likely resulted in failure to consistently identify mussels correctly. Important management decisions and project implementations require accurate assessment of species' localities and populations. Incorrect species identification could hinder species' recovery efforts or prevent projects that otherwise could have continued if species are misidentified. If a mussel collection is thought to be a new record or could affect a project, I recommend that molecular genetic identifications be used to verify the species identity.