Nitrogen limitation theory predicts that terrestrial plants should benefit from nitrogen inputs and that herbivores should benefit from subsequent higher plant protein contents. While this pattern has generally been supported, some herbivorous insects have shown preference and higher performance on low protein (p), high carbohydrate (c) diets as juveniles. However, little is known about the effects on reproduction in adults. Using nitrogen fertilizer, we demonstrate that high plant p:c has negative effects on Senegalese locust (Orthoptera: For this, we measured p:c in millet plants We found that fertilization increased p:c ratio in a concentration‐dependent fashion. We counted the number of locusts alive over the course of 2 weeks and showed that fewer females survived on fertilized plants than on control plants. Females that ate plants from the high fertilization treatment laid lighter eggs. Finally, we showed that female locusts prefer unfertilized plants to plants with a high p:c. We hypothesize that this pattern will apply broadly to species that have extensive carbohydrate needs, such as long‐distance migrators. Because many ecological studies focus primarily on nitrogen or protein, and fail to consider carbohydrates, this study has important implications for how ecologists consider nutrient limitation of primary consumers in ecosystems globally.
Desert locusts These events give us cause to reflect on the natural history of locusts, our fraught relationship with them, and how they are represented in American popular culture and others. Symbolic representations span millennia and most have roots in the natural life cycle of locusts—they transform, they swarm, they devastate specific food crops. There is strong tendency to exaggerate the body size of locusts and the effectiveness of control efforts. Expressions of human futility are rare except in the form of ironic humour. We conclude by suggesting that we humans indulge in hyperbole and humour to normalize and inure ourselves to the psychologically unbearable, and that this tendency is a precondition for the techno‐optimism that drives anti‐locust technologies. There is no substitute for effective monitoring and management programs, but the importance of new and emerging anti‐locust technologies is expected to increase with projections of increased cyclone activity in the northern Indian Ocean.
A free
- NSF-PAR ID:
- 10386704
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- People and Nature
- Volume:
- 3
- Issue:
- 3
- ISSN:
- 2575-8314
- Page Range / eLocation ID:
- p. 542-549
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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