Adaptation to a novel family environment involves both apparent and cryptic phenotypic changes

Cryptic evolution occurs when evolutionary change is masked by concurrent environmental change. In most cases, evolutionary changes in the phenotype are masked by changing abiotic factors. However, evolutionary change in one trait might also be masked by evolutionary change in another trait, a phenomenon referred to as evolutionary environmental deterioration. Nevertheless, detecting this second type of cryptic evolution is challenging and there are few compelling examples. Here, we describe a likely case of evolutionary environmental deterioration occurring in experimental burying beetle (Nicrophorus vespilloides) populations that are adapting to a novel social environment that lacks post-hatching parental care. We found that populations rapidly adapted to the removal of post-hatching parental care. This adaptation involved clear increases in breeding success and larval density (number of dispersing larvae produced per gram of breeding carcass), which in turn masked a concurrent increase in the mean larval mass across generations. This cryptic increase in larval mass was accomplished through a change in the reaction norm that relates mean larval mass to larval density. Our results suggest that cryptic evolution might be commonplace in animal families, because evolving trophic and social interactions can potentially mask evolutionary change in other traits, like body size.The authors were supported by a Consolidator's Grant from the European Research Council (310785 Baldwinian Beetles) to R.M.K. R.M.K. had additional support from a Wolfson Merit Award from the Royal Society. The research was also funded by the Natural Environment Research Council, UK (NE/H019731/1), the European Research Council and the Department of Zoology at the University of Cambridge

Traits across trophic levels interact to influence parasitoid establishment in biological control releases

A central goal in ecology is to predict what governs a species’ ability to establish in a new environment. One mechanism driving establishment success is individual species’ traits, but the role of trait combinations among interacting species across different trophic levels is less clear. Deliberate or accidental species additions to existing communities provide opportunities to study larger scale patterns of establishment success. Biological control introductions are especially valuable because they contain data on both the successfully established and unestablished species. Here, we used a recent dataset of importation biological control introductions to explore how life-history traits of 132 parasitoid species and their herbivorous hosts interact to affect parasitoid establishment. We find that of five parasitoid and herbivore traits investigated, one parasitoid trait—host range—weakly predicts parasitoid establishment; parasitoids with higher levels of phylogenetic specialization have higher establishment success, though the effect is marginal. In addition, parasitoids are more likely to establish when their herbivore host has had a shorter residence time. Interestingly, we do not corroborate earlier findings that gregarious parasitoids and endoparasitoids are more likely to establish. Most importantly, we find that life-history traits of the parasitoid species and their hosts can interact to influence establishment. Specifically, parasitoids with broader host ranges are more likely to establish when the herbivore they have been released to control is also more of a generalist. These results provide insight into how multiple species’ traits and their interactions, both within and across trophic levels, can influence establishment of species of higher trophic levels

Non-target attack of the native stink bug, Podisus maculiventris by Trissolcus japonicus, comes with fitness costs and trade-offs

Accidentally introduced parasitoids can provide biological control of the invasive pest they followed but could also pose a threat to native species if they are not specialists. Attack of native species could reduce the effectiveness of adventive natural enemies if it is accompanied by reduced fitness, and it may increase acceptance of non-target species. We tested how intermittent host shift and prolonged exposure to a non-target, native species Podisus maculiventris (Say) (Hemiptera: Pentatomidae) may affect the fitness and host acceptance of the egg parasitoid, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae) that was co-introduced with the invasive Halyomorpha halys (Stål) (Hemiptera: Pentatomidae). In the first experiment, replicate parasitoid populations were reared either with or without a history of host switching over a 10-generation period between the native and the invasive stink bug that was followed by three generations of continuous reproduction on either host. In the second experiment, replicated populations were exposed for three continuous generations to either the native or invasive host. Occasional or prolonged reproduction on the native host did not increase acceptance and developmental success on the non-target species. Emergence rate of T. japonicus was consistently lower when it reproduced on the native stink bug. There was also a trade-off for the parasitoid, in terms of reduced emergence rate, when switching back to H. halys from the native host. These results suggest that host shifts to native species could reduce the effectiveness of T. japonicus at attacking H. halys, but the fitness costs may prevent significant non-target effects in nature

Data from: Parental care and sibling competition independently increase phenotypic variation among burying beetle siblings

Several recent hypotheses suggest that parental care can influence the extent of phenotypic variation within populations; however, there have been few tests of these ideas. We exploited the facultative nature of post-hatching parental care in the burying beetle, Nicrophorus vespilloides, to test whether parental care influences the expression of phenotypic variation in an important fitness trait (body size). We found that parental care and brood size (which influences sibling competition) had positive and independent effects on variation in body size. First, the mean coefficient of variation (CV) of body size was significantly greater in broods that received care than in those that did not. Second, CV body size increased with brood size in both parental care treatments. These results are not consistent with predictions from recent hypotheses that predict parental care will reduce phenotypic variation among siblings. The positive effects of parental care and brood size on phenotypic variation that we observed are likely due to sibling competition for access to provisioning parents and competition for limiting resources contained in the breeding carcass. Our results suggest that future theory linking parental care to the generation and maintenance of phenotypic variation must integrate the nature of interactions among family members

Limited gains in native parasitoid performance on an invasive host beyond three generations of selection

Co-evolved natural enemies provide sustainable and long-term control of numerous invasive insect pests, but the introduction of such enemies has declined sharply due to increasing regulations. In the absence of co-evolved natural enemies, native species may attack exotic invasive pests; however, they usually lack adaptations to control novel hosts effectively. We investigated the potential of two native pupal parasitoids, Pachycrepoideus vindemmiae and Trichopria drosophilae, to increase their developmental success on the invasive Drosophila suzukii. Replicated populations of the two parasitoids were subjected to 10 generations of laboratory selection on D. suzukii with Drosophila melanogaster serving as the co-evolved host. We assessed developmental success of selected and control lines in generations 0, 3, and 10. Changes in host preference, sex ratio, development time, and body size were measured to evaluate correlated responses with adaptation. Both parasitoid species responded rapidly to selection by significantly increasing their developmental success on the novel host within three generations, which remained constant for seven additional generations without further improvement. The generalist parasitoid species P. vindemmiae was able to reach similar developmental success as the control populations, while the performance of the more specialized parasitoid T. drosophilae remained lower on the novel than on the co-evolved host. There was no increase in preference towards the novel host over 10 generations of selection nor were there changes in development time or body size associated with adaptation in either parasitoid species. The sex ratio became less female-biased for both parasitoids after three generations of selection but rebounded in P. vindemmiae by generation 10. These results suggest that a few generations of selection may be sufficient to improve the performance of native parasitoids on invasive hosts, but with limits to the degree of improvement for managing invasive pests when exotic co-evolved natural enemies are not available

An evolutionary switch from sibling rivalry to sibling cooperation, caused by a sustained loss of parental care

Sibling rivalry is commonplace within animal families, yet offspring can also work together to promote each other’s fitness. Here we show that the extent of parental care can determine whether siblings evolve to compete or to cooperate. Our experiments focus on the burying beetle Nicrophorus vespilloides, which naturally provides variable levels of care to its larvae. We evolved replicate populations of burying beetles under two different regimes of parental care: Some populations were allowed to supply posthatching care to their young (Full Care), while others were not (No Care). After 22 generations of experimental evolution, we found that No Care larvae had evolved to be more cooperative, whereas Full Care larvae were more competitive. Greater levels of cooperation among larvae compensated for the fitness costs caused by parental absence, whereas parental care fully compensated for the fitness costs of sibling rivalry. We dissected the evolutionary mechanisms underlying these responses by measuring indirect genetic effects (IGEs) that occur when different sibling social environments induce the expression of more cooperative (or more competitive) behavior in focal larvae. We found that indirect genetic effects create a tipping point in the evolution of larval social behavior. Once the majority of offspring in a brood start to express cooperative (or competitive) behavior, they induce greater levels of cooperation (or competition) in their siblings. The resulting positive feedback loops rapidly lock larvae into evolving greater levels of cooperation in the absence of parental care and greater levels of rivalry when parents provide care

Experimental adaptation of native parasitoids to the invasive insect pest, Drosophila suzukii

The spread of invasive pests is increasing due to greater global transportation and climate change-mediated range shifts. In a new community, these invasive species provide a novel resource that native predators or parasitoids can evolve to utilise. For invasive agricultural pests, this could provide top-down control; however, initial attack rates on invasive species in the wild are generally low. The potential for rapid adaptive evolution of native species to improve developmental success on invasive species is unknown. We address this by focusing on Drosophila suzukii, a polyphagous invasive pest, and two cosmopolitan Drosophila parasitoids found in North America prior to the arrival of D. suzukii (Pachycrepoideus vindemiae and Trichopria drosophilae). We experimentally evolved three replicate populations of both species on D. suzukii and the cosmopolitan D. melanogaster, a common host for both parasitoids. We found evidence that P. vindemiae increased developmental success by 88% (95% credible intervals = [−14%, 254%]) and T. drosophilae increased developmental success by 259% [38%, 711%] on D. suzukii after only three generations of selection, despite very low founding sizes of 2 and 30 wasps, respectively. These results demonstrate that rapid evolution of increased virulence is possible even from low genetic diversity, with implications for integrating evolutionary techniques into biological control of invasive species

Forest gaps, edge, and interior support different ant communities in a tropical peat-swamp forest in Borneo

Southeast Asia’s tropical peat-swamp forests (TPSF) are globally important for carbon storage and biodiversity conservation, but are at risk from multiple threats and urgently require improved management. Ants are often used as ecological indicators in monitoring programmes to guide adaptive management, but data on TPSF ants are scarce. We conducted a twelve-month study on ants in the Sabangau TPSF in Indonesian Borneo using baited traps, to compare community composition across three disturbance categories (forest gaps, forest edge and relatively undisturbed interior forest) and between dry and wet season. The three disturbance categories supported distinct ant communities across seasons. Differences in canopy cover likely underlie these changes in ant community composition. Surveying was more effective in the dry season, because ant capture rates were higher and more indicator taxa were identified than in the wet season, but overall ant community composition did not differ significantly between seasons. These findings suggest a potentially useful role of ants as ecological indicators in TPSF. Further surveys should be conducted in Sabangau and other TPSFs to test the transferability of our findings

Don’t Touch My MIDI Cables: Gender, Technology and Sound in Live Coding

Live coding is an embodied, sensorial and live technological–human relationship that is recursively iterated through sonic and visual outputs based on what we argue are kinship relations between and through bodies and technology. At the same time, and in a familiar moment of déjà vu for feminist scholars, live coding is most often discussed not in relation to the lived and sensory human–technology kinship, but in terms of fetishised code or software, output and agency. As feminist scholars have long argued, emphasising and fetishising code or software, and celebrating output and agency are normatively masculine, white and Western conceptions of technology that feed into the growing valorisation of accelerationist logic whilst also negating embodied, not to mention other (non-white, Western, masculine) bodies, expertise or histories per se. In this article, we want to redress this by drawing on our empirical material on live coding to focus on human–technology kinship and, in so doing, think about failure, slowness and embodiment and about human–technology relations that are more akin to what Alison Kafer (drawing on the work of Donna Haraway) has termed ‘becoming with’ or ‘making kin’. This, we argue, has the potential to shift the focus from the potentialities of technologies on or through the body, towards the generative capacities of mediation (including failure), which are caught up in lived experiences. The question is not only about how the relations of bodies and technologies are played out in certain circumstances but about what might be played out if we reconceptualise these relations in these terms

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale