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Biology subjects

Pickles, R.

Publications and source records attributed to Pickles, R..

2 recordsLinked to original sources

Synthetic Substitutes as a Conservation Tool: Evaluating Synthetic Leopard Fur for Demand Reduction and Species Recovery

Providing synthetic substitutes is a widely promoted strategy to shift consumer demand away from wildlife products derived from threatened species. Yet, there is little evidence on whether such product substitution interventions effectively prevent illegal or unsustainable harvesting and contribute to the recovery of threatened populations. Drawing on the Furs For Life (FFL) Zambia initiative, which supplied synthetic furs known as "Heritage Furs" to replace leopard skins traditionally worn during Lozi royal ceremonies in Western Zambia, we present an evaluation designed to test both the effects and causal mechanisms of substitution. Guided by the EMMIE framework, commonly used in crime prevention evaluation, we triangulated data from semi-structured questionnaires, law enforcement patrols, court records, camera trap monitoring, and stakeholder interviews conducted between 2018 and 2024. Qualitative analysis using the General Elimination Method was employed to assess plausible alternative explanations for leopard recovery. By 2024, adoption of synthetic furs among leopard fur users exceeded 80 percent, while self-reported ownership of authentic leopard furs declined by 70 percent. At the same time, patrol detections of leopard poaching incidents decreased, and camera trap density estimates increased from an average of 2.7 to 3.8 leopards per 100 square kilometers across the focal landscape. An integrated mechanism of change, derived from stakeholder perspectives, indicates that while substitution reduced demand, concurrent and reinforcing effects of counter-poaching and counter-trafficking operations were critical to leopard recovery. This study provides the first empirical link between a demand reduction initiative based on synthetic substitutes and measurable species population recovery.

ecology↗

Modeling predicts mechanisms altered by mutations of the SARS-CoV-2 delta and omicron variants

We apply our mechanistic, within-host, pre-immunity, respiratory tract infection model for unvaccinated, previously uninfected, and immune-compromised individuals. Starting from published cell infection and viral replication data for the SARS-CoV-2 alpha variant, we explore variability in outcomes of viral load and cell infection due to three plausible mechanisms altered by SARS-CoV-2 mutations of delta and omicron. We seek a mechanistic explanation of clinical test results: delta nasal infections express [~]3 orders-of-magnitude higher viral load than alpha, while omicron infections express an additional 1 to 2 orders-of-magnitude rise over delta. Model simulations reveal shortening of the eclipse phase (the time between cellular uptake of the virus and onset of infectious viral replication and shedding) alone can generate 3-5 orders-of-magnitude higher viral load within 2 days post initial infection. Higher viral replication rates by an infected cell can generate at most one order-of-magnitude rise in viral load, whereas higher cell infectability has minimal impact and lowers the viral load.

immunology↗