Use of time in a decision‐making process by a parasitoid

Abstract

1. Time perception is seldom studied in invertebrates, with the limited experimental evidence being insufficient to provide a comprehensive pattern of the capacity of invertebrates to measure time and use it in decision‐making processes. 2. In this study, it was hypothesized that insect parasitoids have evolved the capacity to measure time precisely and to use it to optimize foraging decisions related to host exploitation. To examine time perception in females of the gregarious egg parasitoid Trichogramma euproctidis, the present study used their ability to adjust their investment (number of eggs laid) in a host to the initial transit duration (interval between the first contact with the host and the following contact with the substrate). Females utilize this method to assess host egg size, as a large egg necessarily requires more time to evaluate than a small host. In this study, the initial transit duration for a given sized egg was artificially extended by suspending it. 3. For similar sized hosts, female T. euproctidis significantly increased both oviposition duration and progeny allocation following a longer initial transit duration. 4. These results demonstrate the intrinsic capacity of this parasitoid to measure time and to adjust their progeny investment accordingly. This is believed to be one of the few demonstrations of a retrospective measure of time in an invertebrate.

Egg laying rather than host quality or host feeding experience drives habitat estimation in the parasitic wasp Nasonia vitripennis

“…Here, we cannot distinguish whether absolute number of hosts or the host encounter rate (integrating time in between egg laying events) is used by N. vitripennis females as a measure of habitat quality. Females of the parasitoid Trichogramma euproctidis have recently been shown to perceive time and use it in their decision‐making processes (Parent, Brodeur, & Boivin, ). Nasonia vitripennis females might thus integrate time between egg laying events or use time since last oviposition as a measurement of habitat quality (whereby an egg laying event triggers “starting the clock”).…”

The ecological significance of time sense in animals

“…For example, parasitoid Trichogramma wasps adjust their reproductive investment in a host based on the host egg size. They measure egg size with a temporal odometer by timing the travel duration from first contact with the egg, to contact with the substrate (Schmidt & Smith, 1987; Parent et al ., 2016). In this case, a temporal odometer is reliable as the distance is very short and the insect is likely moving at a relatively constant speed.…”

“…Schmidt & Smith (1987);Parent, Brodeur, & Boivin (2016) Biological Reviews 96 (2021) 526-540 © 2020 Cambridge Philosophical Society…”

Correlated decision making across multiple phases of olfactory guided search in Drosophila

“…For insects, the ability to measure time-intervals on the scale of seconds to minutes is open for debate. Parasitoid wasps are capable of learning time intervals [45,46]. Honeybees, however, are not [47,48].…”