Cocooned Wasp Larvae
Bathyplectes anurus’s (parasitoid wasp) larvae are known to spin cocoons and jump up to 5 centimeters while still inside of them. Scientists have just now believed to have figured out why…
Researchers have found that the larvae jump in their cocoons to find shade. Yoriko Saeki, lead researcher, and her team examined many different effects of light intensities, temperatures and humidity levels under laboratory and field conditions.
The researchers discovered that cocoons in light jumped 3x more often than those kept in darkness. The jumping activity also increase during rapid temperature increase, and where 60% higher in conditions of low humidity.
They also found that when the cocoons were allowed to jump freely, majority of them ended up in shady areas. The cocoons in the shady areas were also more likely to survive, compared to those left out in brighter light.
When researchers put Japanese giant ants into the mix, they found that the cocoons jumped and moved about 83% more when they were placed next to the ants. The Japanese giant ants are known predators of this time of larvae. When the ant made direct contact with a cocoon the frequency of movement decreased.
All results suggested that the larvae responded to environmental stressed by jumping into more favorable habitats of which allowed them to develop unrestrictedly. Overall, the jumping behavior comes at a cost as it required more energy use.