Alternative reproductive tactics (ARTs) are correlated suites of sexually selected traits that are likely to impose differential physiological costs on different individuals. While moderate activity might be beneficial, animals living in the wild often work at the margins of their resources and performance limits. Individuals using ARTs may have divergent capacities for activity. When pushed beyond their respective capacities, they may experience condition loss, oxidative stress, and molecular damage that must be repaired with limited resources. We used the Australian painted dragon lizard that exhibits color polymorphism as a model to experimentally test the effect of exercise on body condition, growth, reactive oxygen species (ROS) and telomere dynamics - a potential marker of stress and aging and a correlate of longevity. For most males, ROS levels tended to be lower with greater exercise; however, males with yellow throat patches - or bibs - had higher ROS levels than non-bibbed males. At the highest level of exercise, bibbed males exhibited telomere loss, while non-bibbed males gained telomere length; the opposite pattern was observed in the no-exercise controls. Growth was positively related to food intake but negatively correlated with telomere length at the end of the experiment. Body condition was not related to food intake but was positively correlated with increases in telomere length. These results, along with our previous work, suggest that aggressive - territory holding - bibbed males suffer physiological costs that may reduce longevity compared with non-bibbed males with superior postcopulatory traits.The voluntary amputation of an appendage, or autotomy, is an effective defensive mechanism that allows an animal to escape aggressive interactions. However, animals may suffer long-term costs that can reduce their overall fitness. Atlantic ghost crabs (Ocypode quadrata) are one of the fastest terrestrial invertebrates, and regularly lose one or more limbs in response to an antagonist encounter. When running laterally at fast speeds, they adopt a quadrupedal gait using their first and second pairs of legs while raising their fourth, and sometimes the third, pair of legs off the ground. This suggests that some limbs may be more important for achieving maximal locomotor performance than others. The goal of this study was to determine whether the loss of certain limbs would affect running performance more than others, and what compensatory strategies were used. Crabs were assigned to four different paired limb removal treatments or the control group and run on an enclosed trackway in their natural habitat. Ghost crabs were found to adjust stride kinematics in response to limb loss. Loss of the second or third limb pairs caused a reduction in running speed by about 25%, suggesting that the remaining intact limbs were unable to compensate for the loss of either limb, either due to a lack of propulsive forces produced by these limbs or issues stemming from re-coupling limb arrangements. Loss of any of the other limbs had no detectable effect on running speed. We conclude that compensatory ability varies depending on the limb that is lost.The ability to entrain to auditory stimuli has been a powerful method to investigate the comparative rhythm abilities of different animals. While synchrony to regular simple rhythms is well documented, synchrony to complex stimuli, with multiple components at unequal time intervals, is rarer. Several katydid species with simple calls have been shown to achieve synchrony as part of their natural calling interactions in multi-individual choruses. Yet no study so far has demonstrated synchrony in any insect with a complex call. Using natural calling behaviour and playback experiments, we investigated acoustic synchrony and the mechanisms underlying it in the katydid species Mecopoda 'Two Part Caller'. https://www.selleckchem.com/products/hexa-d-arginine.html This species has a complex call consisting of a long trill followed by two or more chirps. We found that individual males synchronized trills and, to a lesser extent, chirps. Further investigation of trill synchrony showed that the timing of trills is modified by external trills but not chirps. Chirp synchrony is modified by external chirps, but also by trills. We suggest a qualitative two-oscillator model underlying synchrony in this species and discuss the implications for the evolution of acoustic synchrony.Transgenerational plasticity (TGP) has been identified as a critical mechanism of acclimation that may buffer marine organisms against climate change, yet whether the TGP response of marine organisms is altered depending on their habitat is unknown. Many marine organisms are found in intertidal zones where they experience episodes of emersion (air exposure) daily as the tide rises and recedes. During episodes of emersion, the accumulation of metabolic carbon dioxide (CO2) leads to hypercapnia for many species. How this metabolic hypercapnia impacts the TGP response of marine organisms to climate change is unknown as all previous transgenerational studies have been done under subtidal conditions, where parents are constantly immersed. Here, we assess the capacity of the ecologically and economically important oyster, Saccostrea glomerata, to acclimate to elevated CO2 dependent on habitat, across its vertical distribution, from the subtidal to intertidal zone. Tidal habitat altered both the existing tolerance and transgenerational response of S. glomerata to elevated CO2. Overall, larvae from parents conditioned in an intertidal habitat had a greater existing tolerance to elevated CO2 than larvae from parents conditioned in a subtidal habitat, but had a lower capacity for beneficial TGP following parental exposure to elevated CO2. Our results suggest that the TGP responses of marine species will not be uniform across their distribution and highlights the need to consider the habitat of a species when assessing TGP responses to climate change stressors.Archerfish down a variety of aerial prey from a range of distances using water jets that they adjust to the size and distance of their prey. We describe here that characteristic rapid fin maneuvers, most notably of the pectoral and pelvic fins, are precisely coordinated with the release of the jet. We discovered these maneuvers in two fish, the jets of which had been characterized in detail, that had been trained to shoot from fixed positions at targets at different heights and that remained stable during their shots. Based on the findings in these individuals, we examined shooting-associated fin movement in 28 further archerfish of two species that could shoot from freely chosen positions at targets at different heights. Slightly before the onset of the water jet, at a time when the shooter remains stable, the pectoral fins of all shooters switched from asynchronous low-amplitude beating to a synchronized rapid forward flap. The onset and duration of the forward and subsequent backward flap were robust across all individuals and shooting angles but depended on target height.