Alexander von Humboldt (1769-1859) was one of the most distinguished German scientists of the late 18th and early 19th centuries. His fame came chiefly from his extensive explorations in South ...America and his eminence as a plant naturalist. He attempted to climb the inactive volcano Chimborazo in Ecuador, which was thought to be the highest mountain in the world at the time, and he reached an altitude of about 5,543 m, which was a record height for humans. During the climb, he had typical symptoms of acute mountain sickness, which he correctly attributed to the low level of oxygen, and he was apparently the first person to make this connection. His ability as a naturalist enabled him to recognize the effect of high altitude on the distribution of plants, and by comparing his observations on Chimborazo with those in the European Alps and elsewhere, he inferred that the deleterious effects of high altitude were universal. During his return trip to Europe, he called on President Thomas Jefferson in Washington, where he was given a warm reception, and discussed conservation issues. He then returned to Paris, where he produced 29 volumes over a period of 31 years describing his travels. Here the effects of high altitude on the distribution of plants compared with animals are briefly reviewed. Following Humboldt's death in 1859, there was extensive coverage of his contributions, but curiously, his fame has diminished over the years, and inexplicably, he now has a lower profile in North America.
It is widely acknowledged that data sharing has great potential for scientific progress. However, so far making data available has little impact on a researcher's reputation. Thus, data sharing can ...be conceptualized as a social dilemma. In the presented study we investigated the influence of the researcher's personality within the social dilemma of data sharing. The theoretical background was the appropriateness framework. We conducted a survey among 1564 researchers about data sharing, which also included standardized questions on selected personality factors, namely the so-called Big Five, Machiavellianism and social desirability. Using regression analysis, we investigated how these personality domains relate to four groups of dependent variables: attitudes towards data sharing, the importance of factors that might foster or hinder data sharing, the willingness to share data, and actual data sharing. Our analyses showed the predictive value of personality for all four groups of dependent variables. However, there was not a global consistent pattern of influence, but rather different compositions of effects. Our results indicate that the implications of data sharing are dependent on age, gender, and personality. In order to foster data sharing, it seems advantageous to provide more personal incentives and to address the researchers' individual responsibility.
Vale do Rio Juruá in western Acre, Brazil, is a persistent malaria transmission hotspot partly due to fish farming development that was encouraged to improve local standards of living. Fish ponds can ...be productive breeding sites for Amazonian malaria vector species, including Nyssorhynchus darlingi, which, combined with high human density and mobility, add to the local malaria burden.This study reports entomological profile of immature and adult Ny. darlingi at three sites in Mâncio Lima, Acre, during the rainy and dry season (February to September, 2017). From 63 fishponds, 10,859 larvae were collected, including 5,512 first-instar Anophelinae larvae and 4,927 second, third and fourth-instars, of which 8.5% (n = 420) were Ny. darlingi. This species was most abundant in not-abandoned fishponds and in the presence of emerging aquatic vegetation. Seasonal analysis of immatures in urban landscapes found no significant difference in the numbers of Ny. darlingi, corresponding to equivalent population density during the rainy to dry transition period. However, in the rural landscape, significantly higher numbers of Ny. darlingi larvae were collected in August (IRR = 5.80, p = 0.037) and September (IRR = 6.62, p = 0.023) (dry season), compared to February (rainy season), suggesting important role of fishponds for vector population maintenance during the seasonal transition in this landscape type. Adult sampling detected mainly Ny. darlingi (~93%), with similar outdoor feeding behavior, but different abundance according to landscape profile: urban site 1 showed higher peaks of human biting rate in May (46 bites/person/hour), than February (4) and September (15), while rural site 3 shows similar HBR during the same sampling period (22, 24 and 21, respectively). This study contributes to a better understanding of the larvae biology of the main malaria vector in the Vale do Rio Juruá region and, ultimately will support vector control efforts.
Two hundred eleven years ago, Alexander von Humboldt returned to Europe from South America and began publishing accounts, maps, and diagrams that catalyzed the scientific community's ongoing ...fascination with the diversity of animals and plants on mountains. His essay and famous map of the Geographie des Plantes Equinoxiales followed from his fascination with the rapid change of species diversity with elevation. One hundred sixty years after von Humboldt's first publications (and 50 y ago), Dan Janzen laid out the rationale for why we should consider the isolating effect of mountains relative to their climatic stability-not their absolute height-in his publication "Why mountain passes are higher in the tropics"
The oceanic island of Malpelo, 380 km west of the Colombian mainland, stands out from other islands of the Tropical Eastern Pacific by its harsh environment and depauperate flora and fauna, thus ...imposing strong selective pressure on the small number of invertebrates that inhabit it. The endemic taxon described here, Dyscolus (Cacothrix) malpelensis, n. subgen., n. sp. (Carabidae, Platynini), is a remarkable example of adaptation to this unique ecosystem. The modifications of its body shape, including a tight coaptation of elytra and pronotum, might be a response to strong environmental constraints, from predation by lizards and land crabs to the absence of deep soil that forces the beetle to seek shelter in caves and rock crevices.
Alexander von Humboldt conducted his best-known work on the slopes of the Ecuadorian Andes. He did this by applying his own characteristic brand of multidisciplinary scientific approach. This ...consisted of thorough data collection while synthesizing and visualizing the data in innovative formats. Also important for his scientific success in South America was his collaborative network that helped him to identify specimens and formulate his transformative scientific thoughts. It is no surprise that Humboldt was captivated by Ecuador, as it is one of the most biodiverse places in the world, and this astounding diversity was formed in an intricate, dynamic geological and climatological setting. As of yet, this biodiversity is far from being fully documented and the processes that generated it are still poorly understood. The IBS meeting in Quito 1 and the Second Latin American Congress of Biogeography will form the perfect platform to both commemorate Humboldt while addressing current and unresolved matters concerning the biodiversity of Ecuador and South America at large.
Frederico José de Santa-Anna Nery (1848-1901) was a Brazilian Baron who referred to himself as a "volunteer propagandist" for Brazil in Europe, serving as an immigration agent to publicize the living ...conditions in the Amazon region, advocating for its development and modernization at the end of the nineteenth century. Santa-Anna Nery's most famous book is "Le Pays des Amazones" (The Lands of the Amazons), first published in 1885, which the author dedicated a chapter to introduce and report on the Amazonian useful plant species and its relationship with humans. The aim of this work is to understand the historical context and ethnobotanical value of the plant species in the Brazilian Amazon at the end of the nineteenth century through an analysis of the book "Le Pays des Amazones" (1885) by Baron de Santa-Anna Nery, as well as to bring to light the historical importance of this very influential propagandist, who has been forgotten nowadays.
The original book "Le Pays des Amazones" (1885), as well as the original 3rd edition and its translated version into Portuguese, was carefully analyzed and all information about plants was systematized, with botanical names being updated. Finally, using the scientific name of medicinal plants alone or in combination with their traditional use, a search was carried out in databases in order to indicate current pharmacological studies that provide evidence about the described traditional uses.
A total of 156 plant species were identified in the book, although 132 species had their scientific names updated. These species belong to 45 different families, with Fabaceae and Arecaceae the most represented, and 109 plants are Brazilian native. Considering only the 36 medicinal plants, the main medicinal indications reported were astringent, purgative/laxative, stimulant and tonic, vermifuge, febrifuge, sudorific, emetic, diuretic and antidysenteric. Regarding other useful plants (non-medicinal), 97 species were cited for food, constructions and buildings, spices and condiments, ornaments and objects, carpentry, textile fibers, gums, oils, balms and essences, pigments and tanning, hunting and fishing.
When the book "Le Pays des Amazones" is analyzed from a timeless perspective, with a particular focus on historical ethnobotany, it is possible to observe the economic, social, and political importance of many useful plants for the Amazon at the end of the nineteenth century and how the relationship between local people, indigenous communities, and immigrants was established with plant biodiversity.
With low and markedly seasonal malaria transmission, increasingly sensitive tools for better stratifying the risk of infection and targeting control interventions are needed. A cross-sectional survey ...to characterize the current malaria transmission patterns, identify hotspots, and detect recent changes using parasitological and serological measures was conducted in three sites of the Peruvian Amazon.
After full census of the study population, 651 participants were interviewed, clinically examined and had a blood sample taken for the detection of malaria parasites (microscopy and PCR) and antibodies against P. vivax (PvMSP119, PvAMA1) and P. falciparum (PfGLURP, PfAMA1) antigens by ELISA. Risk factors for malaria infection (positive PCR) and malaria exposure (seropositivity) were assessed by multivariate survey logistic regression models. Age-specific seroprevalence was analyzed using a reversible catalytic conversion model based on maximum likelihood for generating seroconversion rates (SCR, λ). SaTScan was used to detect spatial clusters of serology-positive individuals within each site.
The overall parasite prevalence by PCR was low, i.e. 3.9% for P. vivax and 6.7% for P. falciparum, while the seroprevalence was substantially higher, 33.6% for P. vivax and 22.0% for P. falciparum, with major differences between study sites. Age and location (site) were significantly associated with P. vivax exposure; while location, age and outdoor occupation were associated with P. falciparum exposure. P. falciparum seroprevalence curves showed a stable transmission throughout time, while for P. vivax transmission was better described by a model with two SCRs. The spatial analysis identified well-defined clusters of P. falciparum seropositive individuals in two sites, while it detected only a very small cluster of P. vivax exposure.
The use of a single parasitological and serological malaria survey has proven to be an efficient and accurate method to characterize the species specific heterogeneity in malaria transmission at micro-geographical level as well as to identify recent changes in transmission.
Loop-mediated isothermal DNA amplification (LAMP) methodology offers an opportunity for point-of-care (POC) molecular detection of asymptomatic malaria infections. However, there is still little ...evidence on the feasibility of implementing this technique for population screenings in isolated field settings.
Overall, we recruited 1167 individuals from terrestrial ('road') and hydric ('riverine') communities of the Peruvian Amazon for a cross-sectional survey to detect asymptomatic malaria infections. The technical performance of LAMP was evaluated in a subgroup of 503 samples, using real-time Polymerase Chain Reaction (qPCR) as reference standard. The operational feasibility of introducing LAMP testing in the mobile screening campaigns was assessed based on field-suitability parameters, along with a pilot POC-LAMP assay in a riverine community without laboratory infrastructure.
LAMP had a sensitivity of 91.8% (87.7-94.9) and specificity of 91.9% (87.8-95.0), and the overall accuracy was significantly better among samples collected during road screenings than riverine communities (p≤0.004). LAMP-based diagnostic strategy was successfully implemented within the field-team logistics and the POC-LAMP pilot in the riverine community allowed for a reduction in the turnaround time for case management, from 12-24 hours to less than 5 hours. Specimens with haemolytic appearance were regularly observed in riverine screenings and could help explaining the hindered performance/interpretation of the LAMP reaction in these communities.
LAMP-based molecular malaria diagnosis can be deployed outside of reference laboratories, providing similar performance as qPCR. However, scale-up in remote field settings such as riverine communities needs to consider a number of logistical challenges (e.g. environmental conditions, labour-intensiveness in large population screenings) that can influence its optimal implementation.
The Earth's magnetic field shields our habitat against potentially harmful charged particles from outer space. Moreover, it is an important source of information about Earth's deep interior and ...geological history, both inaccessible to direct observations. Geomagnetism, the study of all aspects of the Earth's magneticfield, formed as a field of natural sciences in the early nineteenth century, largely under the influence of two prominent polymaths, Alexander von Humboldt and Carl Friedrich Gauss. On the occasion of the AGU 2019 centennial and Alexander von Humboldt's 250th anniversary, we link Humboldt's activities in geomagnetism with modern research in this domain and its challenges. Based on magnetic field observations during his scientific journeys, Alexander von Humboldt determined the increase of magnetic intensity with distance from the equator. He initiated coordinated observations across the globe and thus laid the foundation for international data exchange and collaboration. Observation is a prerequisite to a better understanding of the Earth's magnetic field with its various sources from the Earth's core, lithosphere, and electrical current systems outside the Earth, with a multitude of applications from navigation, exploration, natural hazard assessment, and study of Earth's evolution. A full understanding of the physical processes underlying the various geomagnetic field sources is mandatory to tackle the challenge of forecasting the future geomagnetic field evolution and to take advantage of the information that the geomagnetic field can provide about the Earth's history, geological and tectonic conditions and processes, and the near‐Earth's space environment.
Plain Language Summary
Earth's magnetic field shields our planet against highly energetic particles from the Sun and outer space, which threaten modern technology. The main part of the magnetic field originates from dynamical processes in the Earth's outer, fluid core, and changes slowly. Additional contributions are due to magnetized rocks in the uppermost parts of the Earth. Moreover, several quickly varying electrical current systems flowing at distances from approximately 60 km to several Earth's radii around our planet contribute to geomagnetic field observations. Alexander von Humboldt played an important role in establishing the science of geomagnetism. He described the systematic change of magnetic field strength with distance from the equator, and he initiated synchronized magnetic field observations worldwide. Since that time, significant progress has been made in understanding the various geomagnetic field sources, and we have recognized applications ranging from understanding the Earth's geological history, exploration for natural resources, natural hazard assessment, navigation, and protection against adverse space weather influences. Main challenges in geomagnetic field research include a clear separation of signals from the individual field contributions and a full understanding of their physical sources, a more complete understanding of the long‐term history of the geomagnetic field, and forecasting future field changes.
Key Points
Alexander von Humboldt's role as one of the founders of geomagnetism is presented
Current understanding of the various aspects of geomagnetism and paleomagnetism is summarized
Grand challenges in geomagnetism and its societal relevance are outlined
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