In dry conditions, locust babies are born with their first lunch

Gaby Clark
scientific editor

Robert Egan
associate editor

Locusts have undersized babies鈥攚ith their first lunch already in their guts鈥攊n dry conditions. Desert locusts have two distinct modes鈥攕olitary and gregarious鈥攖hat are behaviorally and visibly different. The insects also live in the Sahara desert, an environment with frequent dry conditions.
in PNAS Nexus, Koutaro Ould Maeno and colleagues explored how a lack of moisture and the presence of other locusts shift reproductive resource allocation in the insects. In lab experiments, the authors raised locusts in crowds and in isolation. Crowd-reared females produced fewer, larger eggs than females raised in isolation; large offspring likely have an advantage when there's competition for food.
For both types of locusts, dry conditions produced smaller hatchlings than wet conditions, and the hatchlings in dry conditions were born with a small amount of yolk in their guts鈥攚hat is known as the "lunchbox strategy." With their first meal taken care of, these babies have a bit more energy and time to find plants to eat than hatchlings born with empty stomachs.
For solitary locusts, dry-condition small hatchlings lived 65% longer than normal-sized hatchlings in starvation conditions and hatchlings from desiccated gregarious eggs survived 230% longer than those from wet solitarious eggs in the same conditions.
According to the authors, the results illustrate the complex ways female locusts and embryos living in an unpredictable and harsh ecosystem allocate their reproductive resources.
More information: Koutaro Ould Maeno et al, Desiccated desert locust embryos reserve yolk as a "lunch box" for posthatching survival, PNAS Nexus (2025).
Journal information: PNAS Nexus
Provided by PNAS Nexus