Biology subjects

Jongepier, E.

Publications and source records attributed to Jongepier, E..

4 recordsLinked to original sources

bioRxiv2025

Convergent Evolutionary Traces of Genomic Innovations and Depletions in Socially Parasitic Ants

Parasitism, a common strategy across life, often involves genomic reduction. Socially parasitic "slavemaking" ants provide an excellent model to study the evolution of this lifestyle. Here, we compared the genomes of four closely related, independently evolved parasite-host pairs and their outgroups to identify convergent patterns. While genome size and gene numbers remain relatively stable, parasites show increased positive and relaxed selection, more putative de novo genes which have recently emerged from previously non-coding regions, and a significant loss of chemical receptors, particularly those associated with the evolution of sociality. Hosts, however, retain many duplicated genes. Gene co-expression networks associated with nest-defence in hosts are rather conserved, while the network structure of raiding parasites is much more variable and reflects the independent evolutionary origin of social parasitism. Our findings suggest that while hosts primarily rely on existing molecular mechanisms for defence, parasite genome evolution is characterised by extensive, convergent gene loss, innovation, and network rewiring.

evolutionary biology↗

bioRxiv2021

Evidence for a conserved queen-worker genetic toolkit across slave-making ants and their ant hosts

The ecological success of social Hymenoptera (ants, bees, wasps) depends on the division of labour between the queen and workers. Each caste is highly specialised in its respective function in morphology, behaviour and life-history traits, such as lifespan and fecundity. Despite strong defences against alien intruders, insect societies are vulnerable to social parasites, such as workerless inquilines or slave-making (dulotic) ants. Here, we investigate whether gene expression varies in parallel ways between lifestyles (slave-making versus host ants) across five independent origins of ant slavery in the "Formicoxenus-group" of the ant tribe Crematogastrini. As caste differences are often less pronounced in slave-making ants than non-parasitic ants, we also compare the transcriptomes of queens and workers in these species. We demonstrate a substantial overlap in expression differences between queens and workers across taxa, irrespective of lifestyle. Caste affects the transcriptomes much more profoundly than lifestyle, as indicated by 37 times more genes being linked to caste than to lifestyle and by multiple caste-associated gene modules with strong connectivity. However, several genes and one gene module are linked to the slave-making lifestyle across the independent origins, pointing to some evolutionary convergence. Finally, we do not find evidence for an interaction between caste and lifestyle, indicating that caste differences remain consistent even when species switch to a parasitic lifestyle. Our findings are a strong indication for the existence of a core set of genes whose expression is linked to the queen and worker caste in this ant taxon, supporting the "genetic toolkit" hypothesis.

evolutionary biology↗

bioRxiv2021

Convergent loss of chemoreceptors across independent origins of slave-making in ants

The evolution of an obligate parasitic lifestyle often leads to the reduction of morphological and physiological traits, which may be accompanied by loss of genes and functions. Slave-maker ants are social parasites that exploit the work force of closely related ant species for social behaviours such as brood care and foraging. Recent divergence between these social parasites and their hosts enables comparative studies of gene family evolution. We sequenced the genomes of eight ant species, representing three independent origins of ant slavery. During the evolution of eusociality, chemoreceptor genes multiplied due to the importance of chemical communication in societies. We investigated evolutionary patterns of chemoreceptors in relation to slave-making in ants. We found that slave-maker ant genomes harboured only half as many gustatory receptors as their hosts, potentially mirroring the outsourcing of foraging tasks to host workers. In addition, parasites had fewer odorant receptors and their loss shows patterns of convergence across origins of parasitism, representing a rare case of convergent molecular evolution. This convergent loss of specific odorant receptors suggests that selective deprivation of receptors is adaptive. The 9-exon odorant receptor subfamily, previously linked to social evolution in insects, was significantly enriched for convergent loss across the three origins of slavery in our study, indicating that the transition to social parasitism in ants is accompanied by the loss of receptors that are likely important for mediating eusocial behaviour. Overall, gene loss in slave-maker ants suggests that a switch to a parasitic lifestyle accompanies relaxed selection on chemical perception.

genomics↗

bioRxiv2017

Hemimetabolous genomes reveal molecular basis of termite eusociality

Around 150 million years ago, eusocial termites evolved from within the cockroaches, 50 million years before eusocial Hymenoptera, such as bees and ants, appeared. Here, we report the first, 2GB genome of a cockroach, Blattella germanica, and the 1.3GB genome of the drywood termite, Cryptotermes secundus. We show evolutionary signatures of termite eusociality by comparing the genomes and transcriptomes of three termites and the cockroach against the background of 16 other eusocial and non-eusocial insects. Dramatic adaptive changes in genes underlying the production and perception of pheromones confirm the importance of chemical communication in the termites. These are accompanied by major changes in gene regulation and the molecular evolution of caste determination. Many of these results parallel molecular mechanisms of eusocial evolution in Hymenoptera. However, the specific solutions are remarkably different, thus revealing a striking case of convergence in one of the major evolutionary transitions in biological complexity.

evolutionary biology↗