Biology subjects

Veit, D.

Publications and source records attributed to Veit, D..

4 recordsLinked to original sources

bioRxiv2025

Offspring chemical control of adult reproductive transitions in a social insect

Parental care enhances offspring survival and growth but often entails a trade-off in which caregivers temporarily suppress their own reproduction to invest in existing young. In vertebrates, these parental reproductive cycles are controlled by offspring-derived cues that reduce or suppress parental fertility. While many insects display obligate parental care, the role of offspring cues in regulating adult reproduction remains unresolved outside advanced eusocial taxa, where reproductive cycles have largely been lost. Here, we investigate reproductive cycles in the clonal raider ant Ooceraea biroi, in which totipotent females alternate between caring for larvae and laying eggs. Using custom behavioral assays, we show that larvae inhibit adult reproduction without physical contact, implicating volatile cues. Chemical analyses identified a previously undescribed larva-specific compound, methyl 3-ethyl-2-hydroxy-4-methylpentanoate (MEHMP), which is absent from other developmental stages and ant species. Exposure to synthetic MEHMP recapitulated the inhibitory effect of larval volatiles, confirming its role as a pheromone that suppresses adult egg laying. To our knowledge, this is the first brood pheromone described in ants. By providing a direct chemical link between offspring presence and parental reproductive suppression, our findings underscore the central role of offspring signals in mediating parental reproductive investment across animals that care for their young. Significance StatementParental care enhances offspring survival but induces profound physiological changes in caregivers. A common feature across animals is that adults temporarily suppress their own reproduction while caring for the young. The offspring cues enforcing these cycles remain poorly understood, especially in insects. Using the clonal raider ant Ooceraea biroi, in which all females alternate between reproduction and brood care, we identify a larval pheromone that suppresses adult egg laying. This pheromone is a previously undescribed volatile chemical compound, and exposure to its synthetic version mimics the full biological effect of larvae volatiles. By providing a direct link between offspring presence and adult reproductive suppression, our work highlights how offspring can chemically control the reproduction of their caregivers.

animal behavior and cognition↗

bioRxiv2024

Division of labour underlies efficient colony defence in a clonal ant

The ecological success of social insects is often credited to the division of labour (DOL), yet empirical evidence directly linking DOL to colony efficiency is rare, in part because variation in DOL between colonies is often confounded by variation in colony traits (e.g., group size, genetic diversity) that can independently affect group efficiency. Here, we measure the link between DOL and efficiency in a crucial task, colony defence, in a social insect that affords precise experimental control over relevant individual and colony traits, the clonal raider ant (Ooceraea biroi). We find that DOL in defence behaviour emerges within colonies of near-identical workers, and is consistently associated with enhanced defence efficiency. This positive relationship is robust to variation in the social environment (group size and the presence and type of brood), indicating that the extent of behavioural variation between members of a social group can serve as a key indicator of group efficiency.

animal behavior and cognition↗

bioRxiv2022

Increased ozone levels disrupt insect sexual communication

Insect sexual communication often relies upon sex pheromones1-3. Most insect pheromones, however, contain carbon-carbon double bonds and potentially degrade by oxidation4. Here, we show that already frequently reported increased levels of Anthropocenic ozone can oxidize all described male-specific pheromones of Drosophila melanogaster5-7, resulting in reduced amounts of e.g. cis-Vaccenyl Acetate and (Z)-7-Tricosene. At the same time female acceptance of ozone-exposed males is significantly delayed. Interestingly, groups of ozonized males also exhibit unnaturally high levels of male-male courtship behavior. When repeating similar experiments with nine other drosophilid species, we observe pheromone degradation and/or corrupted sex recognition in eight of them. Our data suggest that Anthropocenic levels of ozone can oxidize double bonds in a variety of insect pheromones extensively, thereby leading to deviations in sexual recognition.

animal behavior and cognition↗

bioRxiv2022

Aversive bimodal associations impact visual and olfactory memory performance in Drosophila

Insects rely heavily on sampling information from their environment for survival and fitness. Different sensory channels with dedicated downstream neural substrates are programmed to fine tune these signals and translate them into usable instructions to mediate complex behaviors. Sensory information can also be learned and stored as memories that influence decisions in the future. The learning of unimodal sensory signals, especially olfaction, has been studied extensively in different conditioning paradigms in different insects. Using the Drosophila melanogaster model in our work, we first investigated differences in the efficiencies of aversive associative visual and olfactory learning using sensory cues that are innately very attractive, such as blue or green light as well as food odors found in fruits or yeast. We then combined the presentation of visual and olfactory sensory stimuli during training to study the effect of bimodal integration on learning performance. When trained unimodally, flies did not easily learn visual stimuli, but when trained bimodally, they developed a significant short-term visual memory after a single learning trial. The bimodal training also suppressed the phototaxis response of the flies to near abolishment. However, a similar training did not enhance the short-term olfactory memory and in some cases, even caused reduction in strength. An enhancement after bimodal training was only seen with a weak long-term olfactory memory retrieved after 24h. Our study demonstrates that bimodal sensory integration is not always synergistic, but is conditional upon the training paradigm and inherent learning abilities of the sensory modalities involved.

animal behavior and cognition↗