Seasonal Variation in Home Range Sizes and Daily Distance to Ephemeral Surface Water for African Savannah Elephant () in Eastern Okavango Panhandle, Northern Botswana.

African elephants () are megaherbivores of the African savannas requiring extensive ranges that can provide critical resources for their survival and reproduction at different spatiotemporal scales. We studied seasonal differences in home range sizes and daily distance to the nearest surface water sources by five male and 10 female African elephants in the eastern Okavango Panhandle in northern Botswana between 2014 and 2017. We hypothesized that (i) elephant home ranges would be larger in the wet than in the dry season (because critical resources tend to be less localized in the wet than in the dry season), (ii) the daily distance of the elephants to the nearest ephemeral surface water sources would be larger in the dry than in the wet season because many of the ephemeral water sources would be dry in the dry season and elephants would start moving towards permanent water sources such as rivers, and lastly (iii) that the differences in elephant home ranges and daily distance to water would differ between sexes.

Do It Well or Not at All: Alternative Flight Solutions for Alpine Insects.

Exposed and isolated alpine ecosystems present evolutionary challenges for flying species worldwide. Many insects have undergone dramatic wing reduction in response to these harsh conditions, losing the ability to fly. By contrast, some taxa have countered alpine conditions by evolving larger wings to improve flight ability.

Remote sensing and spatial analysis reveal unprecedented cyanobacteria bloom dynamics associated with elephant mass mortality.

The 2020 mass mortality of 350 African elephants (Loxodonta africana) in Botswana sparked global concern, with cyanotoxins in watering holes (pans) being a suspected cause, though evidence remains inconclusive. Combining remote sensing and spatial analysis, we examined the relationship between the ecohydrology of ∼3000 pans and the locations of deceased elephants. Our analysis revealed a significant difference in the spatial distribution of fresh versus decayed carcasses (p < 0.

Human-driven evolution of color in a stonefly mimic.

Rapid adaptation is thought to be critical for the survival of species under global change, but our understanding of human-induced evolution in the wild remains limited. We show that widespread deforestation has underpinned repeated color shifts in wild insect populations. Specifically, loss of forest has led to color changes across lineages that mimic the warning coloration of a toxic forest stonefly.

Digest: Repeated body size evolution in island bats.

Island ecosystems represent outstanding natural laboratories for studying the interplay between ecology and evolution. Lavery et al., (2024) use genomic approaches to identify a remarkable example of repeated evolution in Hipposideros bats across the Solomon Islands archipelago.

Genomics reveals repeated landlocking of diadromous fish on an isolated island.

Landlocking of diadromous fish in freshwater systems can have significant genomic consequences. For instance, the loss of the migratory life stage can dramatically reduce gene flow across populations, leading to increased genetic structuring and stronger effects of local adaptation. These genomic consequences have been well-studied in some mainland systems, but the evolutionary impacts of landlocking in island ecosystems are largely unknown.

Freshwater eDNA reveals dramatic biological shifts linked to deforestation of New Zealand.

Deforestation is considered a major threat to biodiversity across many parts of the globe, but the biological impacts of this dramatic ecosystem disturbance often remain incompletely understood. In New Zealand - the world's last major landmass to be colonised by humans - widespread deforestation over recent centuries has left a highly fragmented suite of relict forest stands, ideal for assessing anthropogenic biological change. We hypothesise that this widespread environmental disturbance has underpinned repeated and predictable ecological shifts across distinct rivers and regions.

ebony underpins Batesian mimicry in melanic stoneflies.

The evolution of Batesian mimicry - whereby harmless species avoid predation through their resemblance to harmful species - has long intrigued biologists. In rare cases, Batesian mimicry is linked to intraspecific colour variation, in which only some individuals within a population resemble a noxious 'model'. Here, we assess intraspecific colour variation within a widespread New Zealand stonefly, wherein highly melanized individuals of Zelandoperla closely resemble a chemically defended aposematic stonefly, Austroperla cyrene.

Crop diversity and susceptibility of crop fields to elephant raids in eastern Okavango Panhandle, northern Botswana.

Elephants frequently raid crops within their ranges in Africa and Asia. These raids can greatly impact agricultural productivity and food security for farmers. Therefore, there is a need to explore cost-effective measures that would reduce the susceptibility of crops and agricultural fields to elephant raiding, and further promote sustainable human-elephant coexistence.

Rapid adaptation in a fast-changing world: Emerging insights from insect genomics.

Many researchers have questioned the ability of biota to adapt to rapid anthropogenic environmental shifts. Here, we synthesize emerging genomic evidence for rapid insect evolution in response to human pressure. These new data reveal diverse genomic mechanisms (single locus, polygenic, structural shifts; introgression) underpinning rapid adaptive responses to a variety of anthropogenic selective pressures.

Reduced olfactory acuity in recently flightless insects suggests rapid regressive evolution.

Background: Insects have exceptionally fast smelling capabilities, and some can track the temporal structure of odour plumes at rates above 100 Hz. It has been hypothesized that this fast smelling capability is an adaptation for flying. We test this hypothesis by comparing the olfactory acuity of sympatric flighted versus flightless lineages within a wing-polymorphic stonefly species.

Genomic signatures of parallel alpine adaptation in recently evolved flightless insects.

Natural selection along elevational gradients has potential to drive predictable adaptations across distinct lineages, but the extent of such repeated evolution remains poorly studied for many widespread alpine taxa. We present parallel genomic analyses of two recently evolved flightless alpine insect lineages to test for molecular signatures of repeated alpine adaptation. Specifically, we compare low-elevation vs.

Anthropogenic evolution in an insect wing polymorphism following widespread deforestation.

Anthropogenic environmental change can underpin major shifts in natural selective regimes, and can thus alter the evolutionary trajectories of wild populations. However, little is known about the evolutionary impacts of deforestation-one of the most pervasive human-driven changes to terrestrial ecosystems globally. Absence of forest cover (i.

Digest: Dispersal reduction drives rapid diversification in alpine grasshoppers.

Dispersal-associated traits -such as flight ability- influence how species move across the landscape, and can dramatically impact their distributions and patterns of genetic structure. Ortego et al. examine genomic data from two recently diverged alpine grasshopper lineages with distinct wing sizes to assess the demographic impacts of flight loss.

Reinventing the wheel? Reassessing the roles of gene flow, sorting and convergence in repeated evolution.

Biologists have long been intrigued by apparently predictable and repetitive evolutionary trajectories inferred across a variety of lineages and systems. In recent years, high-throughput sequencing analyses have started to transform our understanding of such repetitive shifts. While researchers have traditionally categorized such shifts as either "convergent" or "parallel," based on relatedness of the lineages involved, emerging genomic insights provide an opportunity to better describe the actual evolutionary mechanisms at play.

Genomics Reveals Widespread Ecological Speciation in Flightless Insects.

Recent genomic analyses have highlighted parallel divergence in response to ecological gradients, but the extent to which altitude can underpin such repeated speciation remains unclear. Wing reduction and flight loss have apparently evolved repeatedly in montane insect assemblages and have been suggested as important drivers of hexapod diversification. We test this hypothesis using genomic analyses of a widespread wing-polymorphic stonefly species complex in New Zealand.

The Gene Introgression Approach and the Potential Cost of Genes that Confer Strong Phosphine Resistance in Red Flour Beetle (Coleoptera: Tenebrionidae).

Resistance in pest insects to the grain fumigant phosphine (PH3) poses a threat to trade and food security. The possible pleiotropic effects of PH3 resistance on development and reproduction were investigated in the red flour beetle, Tribolium castaneum (Herbst), by introgressing two genes known to be major contributors to strong resistance (tc_rph1 and tc_rph2) into a susceptible background. The tc_rph2 allele was the G135S variant, whereas the identity of tc_rph1 allele was unknown but could have been one of the three known variants (L119W, V123F, or S349G).

Exploring movement decisions: Can Bayesian movement-state models explain crop consumption behaviour in elephants (Loxodonta africana)?

Animal movements towards goals or targets are based upon either maximization of resource acquisition or risk avoidance, and the way animals move can reveal information about their motivation. We use hidden Markov models (HMMs) fitted in a Bayesian framework and hourly Global Positioning System fixes to distinguish animal movements into distinct states and analyse the influence of environmental variables on being in, and switching to, a particular state. Specifically, we apply our models to understand elephant movement decisions around agricultural fields, and crop consumption.

Phylogenetic divergence of island biotas: Molecular dates, extinction, and "relict" lineages.

Island formation is a key driver of biological evolution, and several studies have used geological ages of islands to calibrate rates of DNA change. However, many islands are home to "relict" lineages whose divergence apparently pre-dates island age. The geologically dynamic New Zealand (NZ) archipelago sits upon the ancient, largely submerged continent Zealandia, and the origin and age of its distinctive biota have long been contentious.

Comparative transcriptomic analysis of a wing-dimorphic stonefly reveals candidate wing loss genes.

Background: The genetic basis of wing development has been well characterised for model insect species, but remains poorly understood in phylogenetically divergent, non-model taxa. Wing-polymorphic insect species potentially provide ideal systems for unravelling the genetic basis of secondary wing reduction. Stoneflies (Plecoptera) represent an anciently derived insect assemblage for which the genetic basis of wing polymorphism remains unclear.

Ecological gradients drive insect wing loss and speciation: The role of the alpine treeline.

Alpine ecosystems are frequently characterized by an abundance of wing-reduced insect species, but the drivers of this biodiversity remain poorly understood. Insect wing reduction in these environments has variously been attributed to altitude, temperature, isolation, habitat stability or decreased habitat size. We used fine-scale ecotypic and genomic analyses, along with broad-scale distributional analyses of ecotypes, to unravel the ecological drivers of wing reduction in the wing-dimorphic stonefly Zelandoperla fenestrata complex.

The complete chloroplast genome of the invasive fern (Cav.) R. Br.

The Old World climbing fern, , is a rapidly spreading environmental weed in Florida, United States. We reconstructed the complete chloroplast genome of from Illumina whole-genome shotgun sequencing, and investigate the phylogenetic placement of this species within the Leptosporangiate ferns. The chloroplast genome is 158,891 bp and contains 87 protein-coding genes, four rRNA genes, and 27 tRNA genes.

Does wing reduction influence the relationship between altitude and insect body size? A case study using New Zealand's diverse stonefly fauna.

Researchers have long been intrigued by evolutionary processes that explain biological diversity. Numerous studies have reported strong associations between animal body size and altitude, but insect analyses have often yielded equivocal results. Here, we analyze a collection database of New Zealand's diverse endemic stonefly fauna (106 species across 21 genera) to test for relationships between altitude and plecopteran body size.