Extent Of Occurrence Research Articles

ESTUDO DAS MUDANÇAS DO USO E OCUPAÇÃO DO SOLO NO MUNICÍPIO DE TERESINA-PI – 1983 à 2005

The objective of this study was to map and characterize soil use and occupation in the city of Teresina-PI, using remote sensing techniques. For the analysis were acquired the aerial images of the year 1983 and satellite images of 2005 – Quick Bird and made the classification of the objects of these with area calculation by the delimitation method. Two thematic classes (vegetation and residential) were defined for the characterization and mapping. The choice of classes took into account elements of greater representativeness in the landscape. After the classification of the images, it was identified the percentage that each thematic class occupies in the municipality. For digital image processing, classification and area calculation, he used a stereoscope, scanner and ArcGis 9.3 software. Therefore, the municipality of Teresina underwent transformations in its landscape. The vegetation suffered a significant decrease turning into buildings as a consequence of the increase of areas of human occupation. However, the results obtained with the procedures performed for this research proved to be efficient for the monitoring and monitoring of landscape transformations. Remote sensing, accompanied by fieldwork contributes to the monitoring of landscape transformations and enables the creation of assistance mechanisms in the planning and organization of the territory.

FETOMATERNAL OUTCOME AMONG PREGNANT WOMEN PRESENTED WITH OBSTETRIC CHOLESTASIS

Obstetric cholestasis is a significant condition in pregnancy, associated with adverse fetomaternal outcomes, particularly at term. Timely diagnosis and management are crucial to mitigate complications. Objective: The aim of this study was to evaluate the fetomaternal outcomes among pregnant women diagnosed with obstetric cholestasis at term. Methods: This cross-sectional study was conducted from January 1, 2024, to July 1, 2024, in the Department of Obstetrics and Gynecology. Consecutive non-probability sampling was used to recruit women aged 18-40 years diagnosed with obstetric cholestasis at term. Patients with acute hepatitis, chronic kidney disease, or drug-induced hepatitis were excluded. Demographic data such as age, BMI, educational status, occupation, socioeconomic status, and residence area were recorded. Fetomaternal outcomes, including emergency cesarean section, sleep disturbances, postpartum hemorrhage, low birth weight (<2.5 kg), APGAR score <7, NICU admission, and meconium-stained liquor, were assessed. Results: A total of 120 patients were included in the study. The mean age of participants was 28.56 ± 6.40 years, and the majority were within the 18-30 years age group. Fetomaternal outcomes showed that 35% of the women required an emergency cesarean section. Sleep disturbances were observed in 54.2%, and postpartum hemorrhage occurred in 11.7% of cases. Low birth weight was recorded in 20.8% of neonates, while 10% had an APGAR score <7. NICU admission was required for 23.3% of the neonates, and meconium-stained liquor was present in 35.8% of deliveries. Conclusion: The study demonstrated significant fetomaternal outcomes in obstetric cholestasis, emphasizing the need for early detection and careful management to reduce complications such as higher rates of emergency cesarean sections, sleep disturbances, postpartum hemorrhage, low birth weight, and NICU admissions.

Choice of open side affects clinical outcomes of unilateral open-door laminoplasty for inconsistent cervical ossification of the posterior longitudinal ligament

BackgroundThe best open side for unilateral open-door laminoplasty (UODL) to treat inconsistent cervical ossification of the posterior longitudinal ligament (OPLL) needs to be identified.MethodsThirty-one individuals with inconsistent OPLL who underwent UODL between January 2016 and December 2018 were retrospectively divided into two groups: when the side of the open door was consistent with the side of the larger ossification occupancy area, patients were placed in the Consistent group; when the side of the open door was contralateral to the side of the larger ossification occupancy area, patients were placed in the Contralateral group. The following parameters were evaluated: neck disability index (NDI) score, Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score, postoperative laminoplasty opening width and angle, and spinal cord diameter ratio. Spinal cord shifts were also evaluated to compare the clinical results between the two groups.ResultsPatient demographics and major problems did not differ significantly between the groups. Transient pain in the deltoid region was more frequent in the Consistent treatment group. The spinal cord diameter ratio, VAS and NDI scores, opening width, and angle in postoperative laminoplasty did not differ significantly between the two groups. The JOA scores improved in the Consistent group. The spinal cord diameter ratio and spinal cord shift were more significantly improved in the Consistent group.ConclusionsFor inconsistent cervical OPLL, the open-door side that was consistent with a larger ossification occupancy area was preferred in UODL.

The Multiple Errands Test-Home Version and Its Association With Driving Potential: A Pilot Study.

Driving is a complex occupation requiring the interplay of high-level cognitive, physical, sensory, and behavioral skills for safe performance. Occupational therapists need to routinely address driving with adults as an occupational performance area. Further research is needed to determine whether performance-based assessment tools can support occupational therapists in screening client driving potential. To conduct a pilot study to determine whether the Multiple Errands Test-Home Version (MET-Home), as a performance-based assessment, either alone or in combination with other assessments, should be further investigated for use by occupational therapists to screen clients' driving potential. Cross-sectional pilot study. Private in-clinic and community setting, including participants' homes. Convenience sampling recruited 28 participants through private occupational therapy driver assessors. Participants underwent a comprehensive in-clinic and behind-the-wheel assessment, as per standard practice, and three additional cognitive tests. Data were summarized with descriptive statistics, and univariate analyses were used to examine the relationships between cognitive assessment scores and driving outcomes. The MET-Home, as a stand-alone tool and in combination with other cognitive assessment scores, was not associated with driving outcomes (pass-fail). However, participant self-assessment of their MET-Home performance was associated with driving outcomes (pass-fail; p = .014). Although our findings suggest that the MET-Home is unlikely to screen for driving potential, further research of performance-based assessment tool use by occupational therapists is needed to support identification of the optimal type and timing of client referral for comprehensive assessment. Plain-Language Summary: The Multiple Errands Test-Home Version (MET-Home) is commonly completed by occupational therapists. Although this pilot study revealed that MET-Home scores were not associated with driving outcomes, performance-based assessments such as the MET-Home have the potential to guide occupational therapists when screening clients to determine when further, comprehensive assessment is indicated.

Isolated in biogeographic islands: discovery of a disjunct population of a fern in Northeastern Atlantic Forest

Brejos Nordestinos (northeastern highland wet forests) is a unique ecosystem within the Northeastern Atlantic Forest. This area encompasses remmants of humid forests above 600 meters in the semi-arid region. These environmental conditions create an optimal ecosystem for the diversification of plants, including ferns. Pico do Jabre in Paraíba state, with an elevation of 1,208 meters above sea level, is an example of Brejo Nordestino. This study reports the occurrence of Pleopeltis pleopeltidis in the Northeastern Atlantic Forest, particularly at Pico do Jabre, a new record of P. pleopeltifolia for Paraíba state, and the local fern flora. Additional records of P. pleopeltidis were found in the municipalities of Triunfo and Floresta, in Pernambuco state, which are also classified as Brejos Nordestinos with elevations exceeding 1,000 m a.s.l. These findings extend the species known extent of occurrence by approximately 40%. The conservation status of P. pleopeltidis is suggested as Vulnerable (VU) across its entire range and Endangered (EN) in Northeast Brazil. The distance between populations in the Northeastern Atlantic Forest and the nearest populations in Bahia state ranges from 763–931 km, indicating a potential disjunction. Although the species occurs in three relatively close Brejos Nordestinos, the fragmented nature of the Northeastern Atlantic Forest results in isolated populations on these biogeographical islands, surrounded by a Caatinga (seasonally dry tropical forest) matrix.

Species of Fungi Recommended in the Red Data Book of the Rostov Region on the Basis of the IUCN Criteria

Using the example of the preparation of the third edition of the Red data book of the Rostov Region (section Fungi), the experience of applying criteria developed by the International Union for Conservation of Nature is presented. Until recently, the assessment of rarity and threats was carried out using traditionally accepted methods in Russia and often allowed for a significant degree of subjectivity. The IUCN criteria are based on quantitative assessments, which permit a more of accurate evaluation of species status and associated threats. The introduction of new assessment criteria frequently results in a notable revision of the lists of species proposed for protection, with the exclusion of a considerable number of species. The application of most criteria in relation to fungi is exceedingly challenging. Criterion B (geographical distribution: extent of occurrence and area of occupancy) is the most adequate, which allows to indirectly assess the degree of threat of extinction of the species in the territory under consideration. Since the IUCN criteria have been developed for assessment at the global level, it is necessary to develop clearer recommendations for work at the regional level regarding the assessment of the area of areal and habitat.

A Study on Socio-Economic Status of Cabbage Growers in Krishnagiri District of Tamil Nadu, India

Rural development is crucial for the development of the nation. Socio-economic status is dynamic in nature. Socio-economic status provides information on the association between certain factors and the livelihood of vegetables growers. In this study; an attempt had been made to understand the reality of cabbage growers. Krishnagiri was purposefully selected. Kelamangalam block was chosen for the study. The aim of the study was to collect data regarding the characteristics of sample farm households and categorize them into closely related sub groups. Total sample size used for this study was 120. Data was collected by a personal interview method. The personal variables, social variables, economic variables, farming related variables are taken into account to summarize the socio-economic status of cabbage farmers. Based on the data, Agriculture was the main occupation in the study area. Majority of sample farmers had moderate experience in farming. Most of sample farmers had smaller land holdings. Most of the farmers were found to be in the low income group.

Building on purposive interpretation outcomes to discern occupational practices from interview-to-the-double results

Studies leading to revised teaching and learning in business have relied on survey questionnaires without recognising multi-party data collection and evaluation procedures. The study demonstrates how the interview-to-the-double (ITTD) approach builds on the purposive interpretation (PI) results in documenting regulated occupation practices to discern a qualification framework. Recent arguments have been made to develop business rescue practitioner capabilities through short skills development programmes (SSDPs) as continuing professional development (CPD) mechanisms. The advocacy for the use of SSDPs to develop practitioner talent in the field recognises the limitations of prior development of practitioners. The study employed the ITTD, a qualitative inquiry approach promoting practice theory, to obtain results on occupational practices in a regulated environment with 11 professional organisations. The occupational practices determine the occupation’s teaching and learning outcomes. The results and conclusions are based on ITTD data collected from practitioner sessions. The practice theory’s tenets guided the assessment of the opportunities to build the ITTD data collection procedures on PI results to document occupational practices needed for the learning and development of business rescue practitioners. The findings show that business rescue practitioners have 11 categories of occupational tasks constituting occupational areas of corporate renewal work. The investigation argues that corporate renewal or rehabilitation practices are unified, outcome-oriented, and enacted practices requiring a distinct competency framework. The paper argues that the ITTD approach can methodically verify occupation practices premised on legal prescripts. The study verified occupational tasks traceable to specific training disciplines not addressed in the SSDPs or in the previous practitioner training. The study illustrates the opportunities to build ITTD procedures on purposive PI results to address problems associated with surveys in practice documentation in the management curriculum development. The rush to use survey instruments to make a case for occupation-specific learning and development programmes provides misleading results if the PI and ITTD-generated data do not complement results from survey procedures. Documenting practices in a regulated occupation requires multiple data collection approaches to determine learning competencies.

Catasetum × vilhenense (Orchidaceae: Catasetinae), a new natural hybrid from the Amazon forest

This study describes a new natural hybrid of Catasetum, C. × vilhenense, from the State of Rondônia (Brazil) found in ombrophilous forests near the Roosevelt River. The hybrid shows intermediate morphological features between its parental species, C. ariquemense and C. multifidum, with specific differences in floral morphology and inflorescence structure. We provide detailed data on its habitat, ecology, and geographic distribution, and a photographic plate of the hybrid. Given its restricted range, limited to a single locality with an area of occupancy (AOO) of less than 10 km², C. × vilhenense may be Critically Endangered (CR) due to habitat loss and fragmentation. An identification key is also proposed for the species and natural hybrids of Catasetum with symmetrical and parallel antennae in the state of Rondônia, contributing to the understanding and classification of this genus in the Amazon forest.

African bat database: curated data of occurrences, distributions and conservation metrics for sub-Saharan bats

Accurate knowledge of species distributions is foundational for effective conservation efforts. Bats are a diverse group of mammals, with important roles in ecosystem functioning. However, our understanding of bats and their ecological importance is hindered by poorly defined ranges, mostly as a result of under-recording. This issue is exacerbated in Africa by the ongoing rapid discovery of new species, both de novo and splits of existing species, and by inaccessibility to museum specimens that are mostly hosted outside of the continent. Here we present the African bat database – a curated set of 17,285 unique locality records of all 266 species of bats from sub-Saharan Africa, vouched for by specimens and/or genetic sequencing, and aligned with current taxonomy. Based on these records, we also present Maxent-based distribution models and calculate the IUCN Red List metrics for Extent of Occurrence and Area of Occupancy. This database and online visualization tool provide an important open-source resource and is expected to significantly advance studies in ecology, and aid in bat conservation.

A Dynamic Algorithm for Measuring Pedestrian Congestion and Safety in Urban Alleyways

This study presents an algorithm for measuring Pedestrian Congestion and Safety on alleyways, wherein pedestrians and vehicles share limited space, making traditional pedestrian density metrics inadequate. The primary objective is to provide a more accurate assessment of congestion and safety in these shared spaces by incorporating both pedestrian and vehicle interactions, unlike traditional methods that focus solely on pedestrians, regardless of road type. Pedestrian Congestion was calculated using Time to Collision (TTC)-based safety occupation areas, while Pedestrian Safety was assessed by accounting for both physical and psychological safety through proxemics, which measures personal space violations. The algorithm dynamically adapts to changing vehicle and pedestrian movements, providing a more accurate assessment of congestion compared to existing methods. Statistical validation through t-tests and K-S (Kolmogorov–Smirnov) tests confirmed significant differences between the proposed method and traditional pedestrian density metrics, while Bland–Altman analysis demonstrated agreement between the two methods. The experimental results reveal that Pedestrian Congestion and Safety varied with time and location, capturing the spatio-temporal characteristics of alleyways. Visual comparisons of Pedestrian Congestion, Safety, and Density further validated that the proposed algorithm provides a more accurate reflection of real-world conditions compared to traditional pedestrian density metrics. These findings highlight the algorithm’s ability to measure real-time changes in congestion and safety, incorporate psychological discomfort into safety calculations, and offer a comprehensive analysis by considering both pedestrian and vehicle interactions.

Gestational hypoxia elicits long-term cardiovascular dysfunction in female guinea pigs

BackgroundGestational hypoxia (GH) has been implicated in the developmental programming of cardiovascular diseases (CVDs) in the offspring, with most studies focusing on males, conversely, the effects on female cardiovascular health remain understudied. We aimed to investigate the impact of GH on the cardiovascular system of female guinea pig offspring from the early postnatal period to adulthood. MethodsPregnant guinea pigs were subjected to normoxic or hypoxic conditions from gestational day 30 until delivery (∼70 days). Female offspring were monitored with biometric parameters and peripheral vascular function (ultrasound) from birth to one year old. In addition, we assessed cardiovascular structure, oxidative stress, inflammatory state (IHC, qPCR, and immunoblot assays), and thoracic aorta reactivity (wire-myography) at one year of age. Key findingsGH increased heart rate and peripheral pulsatility index. At one year old, GH-exposed females exhibited cardiac remodeling, characterized by increased left ventricular luminal area and coronary artery muscle occupation. Furthermore, GH increased aortic vascular wall, intima-media thickness and contractile capacity. This was accompanied by reduced endothelium-dependent vasodilation and enhanced oxidative stress. Additionally, GH increased collagen deposition and oxidative stress in the right ventricle, accompanied by reduced antioxidant enzymes expression and reduced inflammatory mediator levels. SignificanceGH exerts long-lasting effects on the cardiovascular health of female guinea pig offspring, contributing to cardiac remodeling, vascular dysfunction, oxidative stress, and inflammatory changes. These findings highlight the importance of GH as a risk factor for developing CVDs in female offspring and emphasize the need for sex-specific interventions to mitigate adverse long-term gestational effects.

A small area-occupation three-stage OTA with transistor resistance and parasitic capacitance Q-factor modulation for miniaturized communication systems

A small area-occupation, three-stage operational transconductance amplifier (OTA) is proposed for miniaturized communication systems. Our work presents a novel RC impedance attenuation solution composed of transistor resistance and parasitic capacitance mainly modulating the Q-factor (TRPCQM) of complex poles and precisely handles the first zero and the second pole to enlarge unity-gain frequency (UGF). By employing source-drain transconductance equivalent resistance and inexpensive parasitic capacitance in our RC impedance attenuation block, the complex poles can be regulated meanwhile decreasing chip area occupation. Under a supply voltage of 1.2V, the proposed design is validated using a standard 0.18 μm CMOS process, occupying an ultra-small area of 0.00276 mm2. When driving an ultra-large load of over 20 nF, the design achieves a DC gain exceeding 110 dB and a unity-gain frequency (UGF) of more than 2.1 MHz, with a power consumption of only 10.46 μW.

Social Vulnerability and Illegal Occupation in Urban APP Areas: Legal and Environmental Perspectives in Brazil

Objective: This study aims to critically investigate the conflicts generated by the illegal occupation of urban Permanent Preservation Areas (APPs) to analyze the tensions between environmental preservation and the social rights of vulnerable populations. Theoretical Framework: The theoretical foundation is based on critical urbanization theories, as proposed by Lefebvre, Harvey, and Rolnik, which question socio-spatial segregation and the commodification of urban space, providing a solid basis for understanding the conflicts between environmental and social interests in urban areas. Method: The methodology adopted for this research is qualitative, including case studies and analysis of secondary data, such as public policies on land regularization and relevant legal documents. These methods enable an in-depth analysis of the socio-spatial conditions in occupied APPs. Results and Discussion: The results revealed the socio-spatial exclusion that drives marginalized groups to occupy environmentally sensitive areas. The discussion highlights the need for public policies that do not criminalize vulnerable populations but instead integrate housing and environmental preservation fairly. The limitations of the current legal framework and its implications are also discussed. Research Implications: The implications of this research suggest a systemic change in urban public policies, directly influencing urban planning and environmental justice sectors. This study provides insights for the formulation of more inclusive and sustainable policies aligned with the principles of the right to the city and environmental justice. Originality/Value: This study contributes to the literature by offering a critical analysis of conflicts in urban APPs, proposing alternatives that reconcile social justice and environmental preservation. The relevance of this work lies in its contribution to developing more equitable and effective public policies for environmentally sensitive areas in urban contexts.

Hydrogeomorphological Characterization and Flood Vulnerability in A Coastal Watershed: Socioeconomic and Environmental Implications

Objective: The aim of this study is to identify areas potentially vulnerable to flooding events through multicriteria analysis, based on hydrogeomorphological variables and land use. Theoretical Framework: The relationship between humanity and landforms has shaped the occupation and use of space, with human activities altering physiography and disrupting natural processes. Geomorphology is essential to understanding the interaction between natural factors and human activities. Uncontrolled urban growth leads to environmental degradation and ecosystem overload, exacerbated by climate change. In Macaé (RJ), expansion driven by the oil industry has led to the irregular occupation of estuarine and flood-prone areas, increasing risks for the population. This scenario calls for studies that integrate geomorphology and hydrology to understand risk dynamics in watersheds. Method: In addition to hydrogeomorphological characterization, a multicriteria analysis was conducted, involving land use data, slope, and accumulated flow from the coastal watershed, and potential flood-prone areas and populations were analyzed. Results and Discussion: The results revealed that around 77% of the basin's coastal plain is at moderate to high risk of flooding, and this region is located in the urban area. Research Implications: There is a need for integrated management of water resources and urban planning, considering the socioeconomic and environmental vulnerability of flood-prone areas. Originality/Value: The study contributes to a better understanding of fluvial behavior in coastal watersheds impacted by unplanned occupations in their estuaries.

A Lightweight and High Yield Complementary Metal-Oxide Semiconductor True Random Number Generator with Lightweight Photon Post-Processing.

This paper introduces a novel TRNG architecture that employs a wave converter to generate random outputs from the jitter noise in a customized ring oscillator (RO). Using a current-starved inverter, the proposed RO offers the option of operating three different oscillation frequencies from a single oscillator. To assess its performance, the core TRNG proposed in this work was designed with multiple samples, employing various transistor sizes for 28 nm CMOS processes. The measurements show that only a small number of measured TRNG samples passed the randomness NIST SP 800-22 tests, which is a common problem, not only with the proposed TRNG but also with other TRNG structures. To solve this issue, a lightweight post-processing algorithm using the Photon hash function was newly applied to the proposed TRNGs topology. The lightweight Photon hash function-based post-processing was implemented with the proposed TRNG topology in a 28 nm CMOS process. The design occupies 16,498 µm2, with a throughput of 0.0142 Mbps and power consumption of 31.12 mW. Measurements showed significant improvement, with a 50% increase in chips passing the NIST SP 800-22 tests. Compared with the conventional DRBG post-processing method, the proposed lightweight Photon post-processing reduces area occupation by five times and power consumption by 65%.

Multifunctional In‐Memory Analog‐to‐Digital Converter for Next‐Gen Compute‐in‐Memory Systems

Compute‐in‐memory (CIM) technology based on emerging nonvolatile memories (NVMs) has shown promise in enhancing artificial intelligence applications by integrating computation directly within NVM arrays. However, the efficiency of CIM systems is often curtailed by the substantial overhead that is caused by traditional complementary metal‐oxide‐semiconductor (CMOS)‐based analog‐to‐digital converters (ADCs). Here, we report an in‐memory ADC (IMADC) that leverages NVMs to perform the dual functionalities of reference generation and voltage comparison, effectively minimizing the area occupancy and energy consumption, is reported. The IMADC not only significantly outperforms traditional ADCs but also enables the inherent processing of nonlinear activation functions such as the sigmoid function, which is required for neural networks. The IMADC‐based CIM system achieves software‐comparable accuracy in CIFAR‐10 image classification on the VGG‐9 network. The IMADC exhibits significantly reduced area occupancy (45 μm2) and energy consumption (29.6 fJ) compared to conventional CMOS‐based ADCs. The IMADC, compatible with various types of NVMs, demonstrates significant potential for enhancing the efficiency of CIM systems in terms of area occupancy and energy consumption.

A noodle in a haystack: determining the conservation status of the rare and Data Deficient Ravensthorpe Range slider, Lerista viduata

Context One-seventh of the ~157,000 species assessed by the IUCN Red List of Threatened Species are Data Deficient (DD), with insufficient information to assess their extinction risk. Such a statistic is concerning from a conservation perspective because more than half are predicted to be threatened by extinction, yet they are generally neglected from conservation priority. Aims Here, we aimed to improve ecological knowledge, and inform the conservation status of, the DD Ravensthorpe Range slider (Lerista viduata), a historically rare skink confined to Western Australia’s Ravensthorpe Range. Methods A detailed framework was developed to improve data on attributes integral to the species’ IUCN Red List assessment (e.g. distribution, threats, population size): collation of historical records, fieldwork within and around its known range, preserved specimen analysis, on-ground and spatial analysis of threats, and inference from ecologically similar species. Key results We found that L. viduata is threatened under multiple IUCN Red List criteria (B1ab[i,ii,iii,v], B2ab[i,ii,iii,v], C2ab[ii], D2), and overall should be considered Critically Endangered. This status is based on its Extent of Occurrence (32 km2) being <100 km2, occurrence at one location (defined by the threat of fire), and an inferred continuing decline in its distribution and habitat parameters. The species’ small estimated population size (3,514–9,276 mature individuals) also renders it extinction prone. Conclusions We demonstrate that L. viduata, long perceived as DD, should be reclassified as Critically Endangered, and is of the utmost conservation concern. Implications Our study reiterates the need for DD species to receive greater consideration in conservation research and action.

Effect of bionic shield texture on friction behavior of silicon carbide under water lubrication condition

Abstract Reasonable texture parameters can effectively generate local dynamic pressure effects and promote the formation of lubrication film. The synergistic friction reduction mechanism of the shield-shaped texture on the Silicon Carbide (SiC) surface under water-based lubrication conditions between the flow pressure effect and the ‘rolling ball’ effect is investigated by combining simulation analysis and friction experiments. The effects of shield textured surface on the friction and wear characteristics of SiC surface and the characteristics of interfacial polarization electric field under different rotational speeds and different load conditions were analyzed. The results display that synergistic texture lubrication has a beneficial effect on improving tribological properties. The surface with 6% texture area occupancy showed the best tribological characteristics. The surface with a textured area occupancy of 6% displays the optimal tribological properties. Moreover, the friction reduction mechanisms under different working conditions are discussed, with the textured uniformly arranged surfaces being more suitable for high-speed and heavy load (140 N, 2000 rpm) conditions and the textured non-uniformly arranged surfaces being more suitable for low-speed and light load (40 N, 400 rpm) conditions.

Terminal Pleistocene–Early Holocene human occupation in north-central Chile

While a clear human presence may be recognised in the Andes by 12 000–11 000 cal BP, most archaeological research has focused on occupation of the Andean highlands. To understand the initial occupation of inland areas of South America, the authors consider regional connections and spatial exploitation strategies of hunter-gatherers highlighted in a recent survey of Andean sites. Focusing on north-central Chile, artefacts and radiocarbon dates from three rock shelters suggest sporadic and brief occupation during the Terminal Pleistocene–Early Holocene. Co-occurrence of marine and montane resources, the authors argue, demonstrates a strategy of high mobility and local adaptation in early Andean occupation, using rock shelters as landmarks to navigate and learn new landscapes.