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Snails have occupied an important role in the ideology and religion of the ancient American peoples, who considered them to be magical and used them in ritual ceremonies as ornaments, musical instruments, and architectural elements. Today, they are a valuable study system for understanding biodiversity and evolution due to their remarkable ecological and morphological diversity. Given that many endemic snails are of conservation concern, and that most South American species are poorly studied, there is a need to engage the public through understandable and scientifically based language, conveying the importance of biodiversity. However, not all biodiversity can be seen with the naked eye. Herein, we describe how we utilize snails and their shells to engage citizens and train teachers to promote the many different facets of biodiversity. Through design-based research oriented toward educational innovation, we created a teaching–learning sequence with immersive technology through the following stages of work: (1) produce a teaching–learning sequence and accompanying mobile device application (for Android on GooglePlay), (2) evaluate the impact of the educational resource, and (3) conduct research through a pre- and posttest design on the learning outcomes of participants. In this work, we first present the field experience where scientists, teachers, and pre-service teachers worked together to find snails from northern Chile to Chiloé Island. Some results from this research stage are: criteria for designing a teaching–learning sequence (e.g., how to utilize place as an opportunity for learning science with developmentally appropriate technologies identified for every phase of the sequence), modeling relevant phenomena about biodiversity and ecosystems through snails, scaffolding for teachers implementing the sequence, and activities that enhance STEM education. A teaching–learning sequence that addresses snails as study objects for 4th grade is presented and validated, allowing us to continue the next phase of our research with schools. A second article will propose results from implementation, iterations, and their implications. 

Human-induced changes in climate and habitats push populations to adapt to novel environments, including new sensory conditions, such as reduced visibility. We studied how colonizing newly formed glacial lakes with turbidity-induced low-visibility affects anti-predator behaviour in Icelandic threespine sticklebacks. We tested nearly 400 fish from 15 populations and four habitat types varying in visibility and colonization history in their reaction to two predator cues (mechano-visual versus olfactory) in high versus low-visibility light treatments. Fish reacted differently to the cues and were affected by lighting environment, confirming that cue modality and light levels are important for predator detection and evasion. Fish from spring-fed lakes, especially from the highlands (likely more diverged from marine fish than lowland fish), reacted fastest to mechano-visual cues and were generally most active. Highland glacial fish showed strong responses to olfactory cues and, counter to predictions from the flexible stem hypothesis, the greatest plasticity in response to light levels. This study, leveraging natural, repeated invasions of novel sensory habitats, (i) illustrates rapid changes in anti-predator behaviour that follow due to adaptation, early life experience, or both, and (ii) suggests an additional role for behavioural plasticity enabling population persistence in the face of frequent changes in environmental conditions. 

Abstract Newly arrived species on young or remote islands are likely to encounter less predation and competition than source populations on continental landmasses. The associated ecological release might facilitate divergence and speciation as colonizing lineages fill previously unoccupied niche space. Characterizing the sequence and timing of colonization on islands represents the first step in determining the relative contributions of geographical isolation and ecological factors in lineage diversification. Herein, we use genome-scale data to estimate timing of colonization in Naesiotus snails to the Galápagos islands from mainland South America. We test inter-island patterns of colonization and within-island radiations to understand their contribution to community assembly. Partly contradicting previously published topologies, phylogenetic reconstructions suggest that most Naesiotus species form island-specific clades, with within-island speciation dominating cladogenesis. Galápagos Naesiotus also adhere to the island progression rule, with colonization proceeding from old to young islands and within-island diversification occurring earlier on older islands. Our work provides a framework for evaluating the contribution of colonization and in situ speciation to the diversity of other Galápagos lineages. 

The accumulation of species through time has been proposed to have a hump‐shaped relationship on volcanic islands (highest species richness during intermediate stages of an island's lifespan). Change in topographic complexity (TC) of islands over time is assumed to follow the same relationship. However, TC can be measured in different ways and may not have the same impact across taxonomic groups. Here, we quantify TC across the Galápagos Islands and test the assumption that TC follows a predictable trajectory with island age. Subsequently, we ask whether including TC improves statistical models seeking to explain variation in species richness across islands.

Galápagos Archipelago, Ecuador.

Native and endemic terrestrial animals and plants.

For each island, we generated eight TC indices from a 30‐m resolution digital elevation model. We tested for a relationship between each index and island age, and whether it significantly contributes to observed variation in species richness, using 11 different models for 12 taxonomic groups across the Galápagos Islands.

Four TC indices were significantly negatively correlated with either island age or ontogenetic age and only one index followed the hump‐shaped relationship with age. No index consistently contributed to the variation in species richness for all taxonomic groups. However, for all 12 taxonomic groups, incorporating at least one TC index in modelling species richness improved one or more models. The most common TC index improving models was standard deviation of slope, although each index improved at least five models across all taxa. Different factors predicted taxon‐specific richness, and habitat diversity was significant for all taxa.

Topographic complexity is an important component influencing species richness, but its impact likely differs among taxonomic groups and different scales. Therefore, future studies should incorporate broad, multi‐dimensional measures of TC to understand the biological importance of TC.