Humans as niche constructors: Revisiting the concept of chronic anthropogenic disturbances in ecology

Climate change and long-term human behaviour in the Neotropics: an archaeological view from the Global South

In this paper, we argue for the inclusion of archaeology in discussions about how humans have contributed to and dealt with climate change, especially in the long term. We suggest Niche Construction Theory as a suitable framework to that end. In order to take into account both human and environmental variability, we also advocate for a situated perspective that includes the Global South as a source of knowledge production, and the Neotropics as a relevant case study to consider. To illustrate this, we review the mid-Holocene Hypsithermal period in the southern Puna and continental Patagonia, both in southern South America, by assessing the challenges posed by this climate period and the archaeological signatures of the time from a Niche Construction Theory perspective. Finally, we emphasize the importance of these considerations for policymaking. This article is part of the theme issue 'Climate change adaptation needs a science of culture'.

Integrating traditional ecological knowledge into US public land management: Knowledge gaps and research priorities

Traditional Ecological Knowledge (TEK) is an understanding of natural systems acquired through long-term human interactions with particular landscapes. Traditional knowledge systems complement western scientific disciplines by providing a holistic assessment of ecosystem dynamics and extending the time horizon of ecological observations. Integration of TEK into land management is a key priority of numerous groups, including the United Nations and US public land management agencies; however, TEK principles have rarely been enshrined in national-level US policy or planning. We review over 20 years of TEK literature to describe key applications of TEK to ecological understanding, conservation, restoration and land management generally. By identifying knowledge gaps, we highlight research avenues to support the integration of TEK into US public land management, in order to enhance conservation approaches and participation of historically underrepresented groups, particularly American Indian Tribes, in the stewardship of ancestral lands critical to the practice of living cultural traditions.

Realized niche shift of an invasive widow spider: drivers and impacts of human activities

Background

Predicting invasiveness requires an understanding of the propensity of a given species to thrive in areas with novel ecological challenges. Evaluation of realized niche shift of an invasive species in its invasive range, detecting the main drivers of the realized niche shift, and predicting the potential distribution of the species can provide important information for the management of populations of invasive species and the conservation of biodiversity. The Australian redback spider, Latrodectus hasselti, is a widow spider that is native to Australia and established in Japan, New Zealand, and Southeast Asia. We used ecological niche models and ordinal comparisons in an integrative method to compare the realized niches of native and invasive populations of this spider species. We also assessed the impact of several climatic predictor variables and human activity on this niche shift. We hypothesized that human impact is important for successful establishment of this anthropophilic species, and that climatic predictor variables may determine suitable habitat and thus predict invasive ranges.

Results

Our models showed that L. hasselti distributions are positively influenced by human impact in both of the native and invasive ranges. Maximum temperature was the most important climatic variable in predictions of the distribution of native populations, while precipitation seasonality was the most important in predictions of invasive populations. The realized niche of L. hasselti in its invasive range differed from that in its native range, indicating possible realized niche shift.

Conclusions

We infer that a preference for human-disturbed environments may underlie invasion and establishment in this spider species, as anthropogenic habitat modifications could provide shelters from unsuitable climatic conditions and extreme climatic stresses to the spiders. Because Australia and the countries in which the species is invasive have differing climates, differences in the availability of certain climatic conditions could have played a role in the realized niche shift of L. hasselti.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12983-022-00470-z.

Caryocar coriaceum Wittm. (Caryocaraceae): Botany, Ethnomedicinal Uses, Biological Activities, Phytochemistry, Extractivism and Conservation Needs

Caryocar coriaceum is an endemic tree of Brazil, occurring mainly in the northeast region in the Cerrado environment. The species, popularly known as “pequi”, produces fruits that are used in the manufacture of oil for food and medicinal purposes. This work reviewed studies conducted with the species, highlighting its ethnomedicinal use, its pharmacological potential, including its chemical constituents, and its cultural and socioeconomic importance. Information was obtained through the main scientific research platforms. The keyword “Caryocar coriaceum” was used as the main index for searching the following platforms: PubMed^®, PubMed Central^®, SciElo, Scopus^® and Web of Science^TM. The compiled papers demonstrate that C. coriaceum has great medicinal, economic and cultural importance for northeastern Brazil. Popularly, the fruits of C. coriaceum are used to treat broncho-pulmonary diseases (bronchitis, colds and flu). The fixed oil is widely used to relieve pain from various causes in the treatment of inflammation, flu, eczema, burns, fever, rickets, indigestion, heart murmurs, fatigue and erectile dysfunction. Some of these uses are corroborated by pharmacological trials, which have demonstrated the antioxidant, healing, anti-inflammatory, gastroprotective, antinociceptive and antimicrobial properties of the species. Chemically, fatty acids and phenolic compounds are the main constituents recorded for the species. Due to its medicinal properties, the fruits and oil of C. coriaceum have a high commercial demand and are one of the main forms of subsistence activities for local populations. On the other hand, the extractive practice of the fruits, associated with anthropic factors and its physiological nature, makes the species threatened with extinction. Thus, public management policies are highly necessary in order to avoid its extinction.

A Framework for the Eltonian Niche of Humans

Recent research has highlighted several influential roles that humans play in ecosystems, including that of a superpredator, hyperkeystone species, and niche constructor. This work has begun to describe the Eltonian niche of humans, which encompasses humanity's cumulative ecological and evolutionary roles in trophic systems. However, we lack a unifying framework that brings together these strands of research, links them to ecoevolutionary and sociocultural theory, and identifies current research needs. In this article, we present such a framework in hope of facilitating a more holistic approach to operationalizing human roles in trophic systems across an increasingly anthropogenic biosphere. The framework underscores how humans play numerous nuanced roles in trophic systems, from top-down to bottom-up, that entail not only pernicious effects but also benefits for many nonhuman species. Such a nuanced view of the Eltonian niche of humans is important for understanding complex social–ecological system functioning and enacting effective policies and conservation measures.

Ecosystem services show variable responses to future climate conditions in the Colombian páramos

Background

The páramos, the high-elevation ecosystems of the northern Andes, are well-known for their high species richness and provide a variety of ecosystem services to local subsistence-based communities and regional urbanizations. Climate change is expected to negatively affect the provision of these services, but the level of this impact is still unclear. Here we assess future climate change impact on the ecosystem services provided by the critically important páramos of the department of Boyacá in Colombia, of which over 25% of its territory is páramo.

Methods

We first performed an extensive literature review to identify useful species of Boyacá, and selected 103 key plant species that, based on their uses, support the provision of ecosystem services in the páramos. We collated occurrence information for each key species and using a Mahalanobis distance approach we applied climate niche modelling for current and future conditions.

Results

We show an overall tendency of reduction in area for all ecosystem services under future climate conditions (mostly a loss of 10% but reaching up to a loss of 40%), but we observe also increases, and responses differ in intensity loss. Services such as Food for animals, Material and Medicinal, show a high range of changes that includes both positive and negative outcomes, while for Food for humans the responses are mostly substantially negative. Responses are less extreme than those projected for individual species but are often complex because a given ecosystem service is provided by several species. As the level of functional or ecological redundancy between species is not yet known, there is an urgency to expand our knowledge on páramos ecosystem services for more species. Our results are crucial for decision-makers, social and conservation organizations to support sustainable strategies to monitor and mitigate the potential consequences of climate change for human livelihoods in mountainous settings.

Genetic response to human-induced habitat changes in the marine environment: A century of evolution of European sprat in Landvikvannet, Norway

Habitat changes represent one of the five most pervasive threats to biodiversity. However, anthropogenic activities also have the capacity to create novel niche spaces to which species respond differently. In 1880, one such habitat alterations occurred in Landvikvannet, a freshwater lake on the Norwegian coast of Skagerrak, which became brackish after being artificially connected to the sea. This lake is now home to the European sprat, a pelagic marine fish that managed to develop a self-recruiting population in barely few decades. Landvikvannet sprat proved to be genetically isolated from the three main populations described for this species; that is, Norwegian fjords, Baltic Sea, and the combination of North Sea, Kattegat, and Skagerrak. This distinctness was depicted by an accuracy self-assignment of 89% and a highly significant F ST between the lake sprat and each of the remaining samples (average of ≈0.105). The correlation between genetic and environmental variation indicated that salinity could be an important environmental driver of selection (3.3% of the 91 SNPs showed strong associations). Likewise, Isolation by Environment was detected for salinity, although not for temperature, in samples not adhering to an Isolation by Distance pattern. Neighbor-joining tree analysis suggested that the source of the lake sprat is in the Norwegian fjords, rather than in the Baltic Sea despite a similar salinity profile. Strongly drifted allele frequencies and lower genetic diversity in Landvikvannet compared with the Norwegian fjords concur with a founder effect potentially associated with local adaptation to low salinity. Genetic differentiation (F ST) between marine and brackish sprat is larger in the comparison Norway-Landvikvannet than in Norway-Baltic, which suggests that the observed divergence was achieved in Landvikvannet in some 65 generations, that is, 132 years, rather than gradually over thousands of years (the age of the Baltic Sea), thus highlighting the pace at which human-driven evolution can happen.

Variation in behavioral traits of two frugivorous mammals may lead to differential responses to human disturbance

Human activities can lead to a shift in wildlife species' spatial distribution. Understanding the specific effects of human activities on ranging behavior can improve conservation management of wildlife populations in human-dominated landscapes. This study evaluated the effects of forest use by humans on the spatial distribution of mammal species with different behavioral adaptations, using sympatric western lowland gorilla and central chimpanzee as focal species. We collected data on great ape nest locations, ecological and physical variables (habitat distribution, permanent rivers, and topographic data), and anthropogenic variables (distance to trails, villages, and a permanent research site). Here, we show that anthropogenic variables are important predictors of the distribution of wild animals. In the resource model, the distribution of gorilla nests was predicted by nesting habitat distribution, while chimpanzee nests were predicted first by elevation followed by nesting habitat distribution. In the anthropogenic model, the major predictors of gorilla nesting changed to human features, while the major predictors of chimpanzee nesting remained elevation and the availability of their preferred nesting habitats. Animal behavioral traits (body size, terrestrial/arboreal, level of specialization/generalization, and competitive inferiority/superiority) may influence the response of mammals to human activities. Our results suggest that chimpanzees may survive in human-encroached areas whenever the availability of their nesting habitat and preferred fruits can support their population, while a certain level of human activities may threaten gorillas. Consequently, the survival of gorillas in human-dominated landscapes is more at risk than that of chimpanzees. Replicating our research in other sites should permit a systematic evaluation of the influence of human activity on the distribution of mammal populations. As wild animals are increasingly exposed to human disturbance, understanding the resulting consequences of shifting species distributions due to human disturbance on animal population abundance and their long-term survival will be of growing conservation importance.

Local Knowledge and Conservation Priorities of Medicinal Plants near a Protected Area in Brazil

We investigated the influence of socioeconomic factors (age, gender, and occupation) on the local knowledge of medicinal plants in the Araripe National Forest, Brazil, and the priority of conservation of the species as perceived by people. Additionally, priority species for in situ conservation were identified by calculating conservation priority (CP). Initially, free lists were developed with 152 informants in order to identify the plants known and used by them. Based on the most cited plants in these lists, a salience analysis was performed to identify the ten most prominent tree species. In a second moment, through a participatory workshop, these ten species were classified by the perception of local experts as to their environmental availability and intensity of exploitation. Then, the population size of the forest plant species was quantified through a phytosociological sampling and the conservation priority index (CP) of the species was calculated. A total of 214 ethnospecies were cited by the informants, which were identified in 167 species. Local knowledge was influenced by socioeconomic factors, with positive correlation between age and local knowledge and difference in knowledge among professions. Among the ten most prominent tree species in terms of their medicinal importance, Hancornia speciosa was highlighted as a priority for conservation in the experts' perception because it has low environmental availability and a high exploitation rate. The ten species were ordered by the CP differently from the ordering made by the local experts' perception, indicating that people's perception of species conservation status may not correspond to the actual situation in which they are found in the forests. Conservationist measures based on the perception of informants need complementary ecological studies on the species accessed.

Bird diversity along elevational gradients in the Dry Tropical Andes of northern Chile: The potential role of Aymara indigenous traditional agriculture

Understanding diversity patterns along environmental gradients lies at the heart of community ecology and conservation. Previous studies have found variation in bird diversity and density along “natural” elevational gradients in the Tropical Andes Hotspot. However, there is still a lack of knowledge about how bird communities respond to traditional land-use patterns, in association with other multiple drivers, along elevations. In the present study, we investigated biotic, abiotic and anthropogenic sources of variation associated with bird species diversity, density and turnover along a 3000-m elevational gradient, in southern limit of the Tropical Andes Hotspot, northern Chile. Over four seasons, we conducted 472 bird point count surveys and established 118 plots distributed across the Desert, Pre-Puna, Puna and High-Andean belts, where biotic, abiotic and anthropogenic factors were measured. We used mixed-effects models to estimate alpha diversity and multinomial Poisson mixture models to estimate species density, accounting for detectability. Species diversity and density increased until 3300 masl and then declined. This type of elevational pattern is characteristic of dry-based mountains, where environmental conditions are suitable at mid-elevations. Habitats shaped by traditional Aymara indigenous agriculture, associated with relatively high vegetation heterogeneity, hosted the highest values of bird diversity and density. Species turnover was structured by habitat type, while elevational ranges of most species were restricted to three relatively discrete assemblages that replaced each other along the gradient. Our study revealed a hump-shaped relationship between elevation and bird diversity and density in the Dry Tropical Andes Biodiversity Hotspot, supporting a diversity pattern characteristic of dry-based mountains of the world. Traditional Aymara agriculture may have constructed ecological niches for biodiversity at mid-elevations, enhancing vegetation heterogeneity, thus providing resources for resident and rare species. Increasing loss of traditional land-use may present a threat to the bird community in the Tropical Andes Hotspot.