Unveiling the Desert Locust's Adaptation Strategy to Arid Conditions
―Reserved Egg Yolk Prolongs Larval Survival―

JIRCAS, in collaboration with the French Agricultural Research Centre for International Development and the Mauritanian National Desert Locust Centre, has clarified how desert locust embryos improve their survival rates in harsh desert environments, particularly under dry conditions.

Locusts inhabiting the Sahara Desert often face extreme dryness and scarce food resources. Newly hatched larvae may require unique adaptive strategies to survive, but the details of these strategies have remained unclear until now.

This study found that although larvae hatched under dry conditions are smaller than those hatched in wet conditions, they retain more yolk (lipids) within their bodies. These hatchlings can survive for about twice as long as normal individuals even without access to food. Hatchlings in a starvation state had entirely consumed their yolk reserves, and hatchlings produced by removing yolk from their eggs did not experience extended survival. These findings suggest that the reserved yolk serves as an essential energy source, like a "lunch-box," after hatching.

The research results indicate that, as an adaptation strategy to dry environments, locust embryos flexibly allocate yolk—a limited resource—to enhance survival chances even in food-scarce conditions post-hatching. Understanding these adaptive mechanisms in nature is expected to contribute to more accurate predictions of locust population dynamics in the future.

This research was published in the online edition of PNAS Nexus on May 28, 2025 (Japan time).

Authors

Maeno, K.O., Piou, C., Leménager, N., Ould Ely, S., Ould Babah Ebbe, M.A., Benahi, A.S. and Jaavar,M.E.H.

Title

Desiccated desert locust embryos reserve yolk as a 'lunch box' for post-hatching survival

Journal

PNAS Nexus
DOI: https://doi.org/10.1093/pnasnexus/pgaf132

• JIRCAS President: KOYAMA Osamu
• Program Director:
  • FUJITA Yasunari (Food Program)
• Principal Investigators:
  • MAENO Ould Koutaro (Senior Researcher, Crop, Livestock and Environment Division)
• Press Coordinator:
  • OMORI Keisuke (Head, Information and Public Relations Office)
    Press e-mail: koho-jircas@ml.affrc.go.jp