Biology subjects

Karp, D. S.

Publications and source records attributed to Karp, D. S..

4 recordsLinked to original sources

bioRxiv2020

Genetic variation reveals individual-level climate tracking across the full annual cycle of a migratory bird

For migratory species, seasonal movements complicate local climate adaptation, as it is unclear whether individuals track climate niches across the annual cycle. In the migratory songbird yellow warbler (Setophaga petechia), we find a correlation between individual-level wintering and breeding precipitation but not temperature. Birds wintering in the driest regions of the Neotropics breed in the driest regions of North America. Individuals from drier regions also possess distinct morphologies and population responses to varying rainfall. We find a positive association between bill size and breeding season precipitation which, given documented climate-associated genomic variation, might reflect adaptation to local precipitation regimes. Relative abundance in the breeding range is linked to interannual fluctuations in precipitation, but the directionality of this response varies across geography. Together, our results suggest that variation in climate optima may exist across the breeding range of yellow warblers and provide a mechanism for selection across the annual cycle.

evolutionary biology↗

bioRxiv2020

Reducing ecological complexity using the archetype approach - an application to natural pest control

Natural control of crop pests has the potential to complement or replace intensive agricultural practices, but its mainstream application requires reliable predictions in diverse socioecological settings. In lack of a widely accepted model of natural pest control, we review existing modelling approaches and critically examine their potential to provide understanding and predictions across agricultural landscapes. Models that explicitly represent the underlying mechanisms are better positioned to represent the diversity and context sensitivity of natural pest control than correlative models. Such mechanistic models have used diverse techniques to represent crop-pest-enemy combinations at various spatiotemporal scales. However, certain regions of the world and socioeconomic aspects of natural pest control are underrepresented, while modelling approaches are restricted by a fundamental trade-off between generality and realism. We propose that modelling natural pest control across agroecosystems requires a framework of context-specific generalizations, based on empirical evidence and theoretical expectations. Reviewed models of natural pest control indicate potential attributes of such a general predictive framework.

ecology↗

bioRxiv2019

A global synthesis reveals biodiversity-mediated benefits for crop production

Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield-related ecosystem services can be maintained by few abundant species or rely on high richness remains unclear. Using a global database from 89 crop systems, we partition the relative importance of abundance and species richness for pollination, biological pest control and final yields in the context of on-going land-use change. Pollinator and enemy richness directly supported ecosystem services independent of abundance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.

ecology↗

bioRxiv2019

ICONIC MANAKINS AND DESPICABLE GRACKLES: COMPARING BIRD-RELATED CULTURAL ECOSYSTEM SERVICES ACROSS BIRDWATCHERS, FARMERS, AND URBANITES IN NORTHWESTERN COSTA RICA

Despite the great cultural and economic benefits associated with birdwatching and other bird-related cultural ecosystem services (CES), little is known about the bird-related CES perceived by people, and how they differ across stakeholder groups and species. The goal of this study was to explore CES across three stakeholder groups in northwestern Costa Rica. We conducted surveys (n=404 total) in which we presented farmers (n=140), urbanites (n=149), and birdwatchers (n=115) with pictures and songs of bird species and collected participants ratings on items designed to measure multiple CES. We found bird-related CES were perceived as six different constructs: identity, bequest, education, birdwatching, acoustic aesthetic, and disservices. The three stakeholder groups varied across these constructs and across species. Specifically, birdwatchers ranked species higher in terms of their education scores and lower in disservices scores compared to the other two groups. Positive correlations across CES, and negative correlations with disservices, suggest that the affect heuristic (by which generalized positive or negative feelings sway judgements of risks and benefits) might be informing bird-related CES. Our approach represents a novel method for assessing CES that can be adapted and modified for different taxa and multiple geographical contexts.

ecology↗