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Summary 1. Vector‐borne pathogens and parasites can induce changes in the phenotypes of their hosts that influence the frequency and nature of host–vector interactions and hence transmission, as documented by both empirical and theoretical studies. To the extent that implications for transmission play a significant role in shaping the evolution of parasite effects on host phenotypes, we may hypothesize that parasites exhibiting similar transmission mechanisms – and thus profiting from similar patterns of interaction among hosts and vectors – will have correspondingly similar effects on relevant host traits. Here, we explore this hypothesis through a survey and synthesis of literature on interactions among plant viruses, their hosts, and insect vectors. 2. Insect‐vectored plant viruses that differ in their modes of transmission benefit from different patterns of interaction among host plants and vectors. The transmission of persistently transmitted (PT) viruses requires that vectors feed on an infected host for a sustained period to acquire and circulate (and sometimes replicate) virions, then disperse to a new, healthy host. In contrast, non‐persistently transmitted (NPT) viruses are effectively transmitted when vectors briefly probe infected hosts, acquiring virions, then rapidly disperse. 3. Based on these observations, and empirical evidence from our previous work, we hypothesized that PT and NPT viruses will exhibit different effects on aspects of host phenotypes that mediate vector attraction to, arrestment on and dispersal from infected plants. Specifically, we predicted that both PT and NPT viruses would tend to enhance vector attraction to infected hosts, but that they would have contrasting effects on vector settling and feeding preferences and on vector performance, with PT viruses tending to improve host quality for vectors and promote long‐term feeding and NPT viruses tending to reduce plant quality and promote rapid dispersal. 4. We evaluated these hypotheses through an analysis of existing literature and found patterns broadly consistent with our expectations. This literature synthesis, together with evidence from other disease systems, suggests that transmission mechanisms may indeed be an important factor influencing the manipulative strategies of vector‐borne pathogens, with significant implications for managing viral diseases in agriculture and understanding their impacts on natural plant communities. Lay Summary

This article presents a deep reinforcement learning (DRL) approach for adaptive robotic grasping in dynamic environments. We developed UR5GraspingEnv, a PyBullet-based simulation environment integrated with OpenAI Gym, to train a UR5 robotic arm with a Robotiq 2F-85 gripper. Soft Actor-Critic (SAC) and Proximal Policy Optimization (PPO) were implemented to learn robust grasping policies for randomly positioned objects. A tailored reward function, combining distance penalties, grasp, and pose rewards, optimizes grasping and post-grasping tasks, enhanced by domain randomization. SAC achieves an 87% grasp success rate and 75% post-grasp success, outperforming PPO 82% and 68%, with stable convergence over 100,000 timesteps. The system addresses post-grasping manipulation and sim-to-real transfer challenges, advancing industrial and assistive applications. Results demonstrate the feasibility of learning stable and goal-driven policies for single-arm robotic manipulation using minimal supervision. Both PPO and SAC yield competitive performance, with SAC exhibiting superior adaptability in cluttered or edge cases. These findings suggest that DRL, when carefully designed and monitored, can support scalable learning in manipulation tasks.

In this paper the tip-over stability of mobile robots during manipulation with redundant arms is investigated in real-time. A new fast-converging algorithm, called the Circles Of INitialization (COIN), is proposed to calculate globally optimal postures of redundant serial manipulators. The algorithm is capable of trajectory following, redundancy resolution, and tip-over prevention for mobile robots during eccentric manipulation tasks. The proposed algorithm employs a priori training data generated from an exhaustive resolution of the arm's redundancy along a single direction in the manipulator's workspace. This data is shown to provide educated initial guess that enables COIN to swiftly converge to the global optimum for any other task in the workspace. Simulations demonstrate the capabilities of COIN, and further highlight its convergence speed relative to existing global search algorithms.

Parasites can play a critical role in mediating inter-species interactions. Potential effects induced by parasites can range from species-wide traits to functional alterations in host community structure. One of the most intriguing host–parasite interactions pertains to adaptative host manipulation, an evolutionary occurrence where parasites alter the phenotype of their host to increase their own fitness. This study aims to address this phenomenon in a marine setting by investigating the effect of a philophthalmid trematode, Parorchis sp., on the vertical upward movement and phototactic behaviour of their intermediate hosts whilst simultaneously addressing the host specificity of these effects. These behaviours could impact the odds of trematodes successfully transmitting from their intermediate snail host to their definitive shorebird host, a crucial step in the life cycle of these parasites. Most trematode species exhibit strong specificity for snail hosts, typically infecting only a single snail species. In this rare system, however, the trematode infects a pair of sympatric and congeneric littorinid sea snails found in the intertidal zone of New Zealand’s rocky shores: Austrolittorina cincta and A. antipodum. Precisely, experiments were conducted in a controlled, laboratory-based setting, extending over a period of six weeks, during which vertical displacement and response to light were measured. Our results demonstrate that vertical upward movement amongst infected snails increased for A. cincta, but not for A. antipodum. No difference in response to light between infected and uninfected groups was evident across either species. Our findings highlight the complex nature of parasitic infections, where trait-specific behavioural effects are dissimilar across even congeneric host taxa.

Parasites relying on trophic transmission to complete their life cycles often induce modifications of their host's behavior in ways that may increase their susceptibility to predation by final hosts. These modifications have often been interpreted as parasite adaptations, but very few studies have demonstrated that host manipulation has fitness benefits for the parasite. The aim of the present study was to address the adaptive significance of parasite manipulation by coupling observations of behavioral manipulation to estimates of trophic transmission to the definitive host in the natural environment. We show that the acanthocephalan parasite Pomphorhynchus laevis manipulates the drifting behavior of one of its intermediate hosts, the amphipod Gammarus pulex, but not of a sympatric host, the introduced amphipod Gammarus roeseli. We found a 26.3-28.3 times higher proportion of infected G. pulex in the stomach content of one of the definitive hosts of P. laevis, the bullhead Cottus gobio, than in the benthos. No such trend was observed for G. roeseli. The bell-shaped curve of mean parasite abundance (MPA) relative to host size observed in G. pulex also supported an increased predation mortality of P. laevis-infected individuals compared to uninfected amphipods. Again, no such pattern was observed in G. roeseli. Furthermore, our results indicate that the modifications induced by P. laevis are specific to the definitive host and do not increase the risk of predation by inappropriate hosts, here the adult edible frog Rana esculenta. Overall, our study is original in that it establishes, under field conditions, a direct link between parasitic manipulation and increased transmission to the definitive host, and more importantly, identifies the specificity of the manipulation both in the intermediate host species and toward the definitive host.

1. Host manipulation refers to the expression of a host phenotype that is partly under the genetic control of a parasite. This phenomenon can enhance parasite transmission rates and is responsible for biological marvels such as \"Zombie-ants\" and the \"fatal attraction\" of Toxop/asma-infected rodents to their feline predators. Such host manipulation has evolved in all major phylogenetic lineages of parasites and is assumed to enhance the fitness of the parasite. 2. However, the capacity to manipulate is not ubiquitous; that is, many clades of parasites comprise manipulating and non-manipulating species. This pattern leads to the prediction of costs that select against the evolution of manipulation, but this has been difficult to show empirically. 3. In the present study, we used a tripartitate system consisting of chili (Capsicum annuum) plants infected with Pepper golden mosaic virus and colonized by non-vecnon-vector whiteflies (Trialeurodes vaporariorum), to study the effects on viral load when a non-vector herbivore feeds on the infected plants. 4. We observed that virus-infected plants emitted odours that attracted adult white-flies, contained three times more amino acids in the phloem than mock-inoculated controls and supported higher whitefly reproduction as compared to controls. However, viral load decreased almost 100-fold in whitefly-carrying plants, which was associated with a depletion of phloem amino acids. 5. Synthesis. We show that a plant virus can suffer from a reduced within-host reproduction rate when virus-induced alterations of the plant cause a \"fatal attraction\" of a non-vector insect that exploits the altered plant phenotype at its own benefits. The resulting fitness costs might represent a force that can select against the evolution of host manipulation by parasites.

The behavioral phenotypes of hosts may be altered during parasitism, which could favor either the host or the parasite. Pea aphid Acyrthosiphon pisum hosts parasitized by the primary parasitoid wasp Aphidius ervi leave the stems or lower leaf surfaces where they are most commonly found and move to upper leaf surfaces before they die and mummify. In order to test whether the change of microhabitat benefits the host or the parasitoid, we transplanted pea aphid mummies reared in the laboratory to three different microhabitats on alfalfa plants in the field: the upper leaf surfaces, the lower leaf surfaces, and the stems. Survival analysis revealed no significant differences in mummy survival to emergence across the microhabitat treatments before an alfalfa harvest, when predation pressure was very high, and 2 weeks after an alfalfa harvest, when predation pressure was very low. In contrast, 5 weeks after an alfalfa harvest, when predation pressure was intermediate differences in predation risk were apparent: mummies transplanted to the upper leaf surface had the lowest mortality rates, mummies transplanted to the lower surface of leaves had intermediate mortality rates, and mummies transplanted to the stems had the highest mortality rates. Furthermore, a laboratory study suggested that, compared to other plant substrates, mummies on stems were more likely to be preyed upon by the ladybeetle, Hippodamia convergens, which concentrated its search on stems. Our results support the adaptive manipulation hypothesis, in that parasitized aphids appear to induce their host to move to a region of reduced predator foraging, where their risk of attack is reduced.

The ‘adaptive host manipulation’ hypothesis predicts that parasites can enhance their transmission rates via manipulation of their host’s phenotype. For example, many plant pathogens alter the nutritional quality of their host for herbivores that serve as their vectors. However, herbivores, including non-vectors, might cause additional alterations in the plant phenotype. Here, we studied changes in the amino acid (AA) content in the phloem of chilli ( Capsicum annuum ) plants infected with Pepper golden mosaic virus (PepGMV) upon subsequent colonization with a non-vector, the phloem-feeding whitefly ( Trialeurodes vaporariorum ). Virus infection alone caused an almost 30-fold increase in overall phloem AAs, but colonization by T. vaporariorum completely reversed this effect. At the level of individual AAs, contents of proline, tyrosine, and valine increased, and histidine and alanine decreased in PepGMV -infected as compared to control plants, whereas colonization by T. vaporariorum caused decreased contents of proline, tyrosine, and valine, and increased contents of histidine and alanine. Overall, the colonization by the whitefly had much stronger effects on phloem AA composition than virus infection. We conclude that the phloem composition of a virus-infected host plant can rapidly change upon arrival of an herbivore and that these changes need to be monitored to predict the nutritional quality of the plant in the long run.

Our ability to grab, hold, and manipulate objects involves our dexterous hands, our sense of touch, and feedback from our eyes and muscles that allows us to maintain a controlled grip. Billard and Kragic review the progress made in robotics to emulate these functions. Systems have developed from simple, pinching grippers operating in a fully defined environment, to robots that can identify, select, and manipulate objects from a random collection. Further developments are emerging from advances in computer vision, computer processing capabilities, and tactile materials that give feedback to the robot. Science , this issue p. eaat8414 Dexterous manipulation is one of the primary goals in robotics. Robots with this capability could sort and package objects, chop vegetables, and fold clothes. As robots come to work side by side with humans, they must also become human-aware. Over the past decade, research has made strides toward these goals. Progress has come from advances in visual and haptic perception and in mechanics in the form of soft actuators that offer a natural compliance. Most notably, immense progress in machine learning has been leveraged to encapsulate models of uncertainty and to support improvements in adaptive and robust control. Open questions remain in terms of how to enable robots to deal with the most unpredictable agent of all, the human.

Dexterous manipulation of the robot is an important part of realizing intelligence, but manipulators can only perform simple tasks such as sorting and packing in a structured environment. In view of the existing problem, this paper presents a state-of-the-art survey on an intelligent robot with the capability of autonomous deciding and learning. The paper first reviews the main achievements and research of the robot, which were mainly based on the breakthrough of automatic control and hardware in mechanics. With the evolution of artificial intelligence, many pieces of research have made further progresses in adaptive and robust control. The survey reveals that the latest research in deep learning and reinforcement learning has paved the way for highly complex tasks to be performed by robots. Furthermore, deep reinforcement learning, imitation learning, and transfer learning in robot control are discussed in detail. Finally, major achievements based on these methods are summarized and analyzed thoroughly, and future research challenges are proposed.