B Tissue inside Illness Systems and also Potential Scientific Software

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Social selection occurs when traits of interaction partners influence an individual's fitness and can alter total selection strength. However, we have little idea of what factors influence social selection's strength. Further, social selection only contributes to overall selection when there is phenotypic assortment, but simultaneous estimates of social selection and phenotypic assortment are rare. Here, we estimated social selection on body size in a wild population of New Zealand giraffe weevils (Lasiorhynchus barbicornis). We measured phenotypic assortment by body size and tested whether social selection varied with sex ratio, density and interacted with the body size of the focal individual. Social selection was limited and unaffected by sex ratio or the size of the focal individual. However, at high densities social selection was negative for both sexes, consistent with size-based competitive interactions for access to mates. Phenotypic assortment was always close to zero, indicating negative social selection at high densities will not impede the evolution of larger body sizes. Despite its predicted importance, social selection may only influence evolutionary change in specific contexts, leaving direct selection to drive evolutionary change.Traumatic mating is the male wounding his mate during mating using specialized anatomy. However, why males have evolved to injure their mates during mating remains poorly understood. We studied traumatic mating in Dicerapanorpa magna to determine its effects on male and female fitness. The sharp teeth on male gonostyli penetrate the female genitalia and cause copulatory wounds, and the number of scars on the female genitals is positively related to the number of times females mated. When the injurious teeth were encased with low-temperature wax, preventing their penetration of the female's genitalia during mating, male mating success and copulation duration were reduced significantly, indicating the importance of the teeth in allowing the male to secure copulation, remain in copula and effectively inseminate his mate. The remating experiments showed that traumatic mating had little effect on the female mating refractory period, but significantly reduced female remating duration with subsequent males, probably benefiting the first-mating male with longer copulation duration and transferring more sperm into the female's spermatheca. The copulatory wounds reduced female fecundity, but did not accelerate the timing of egg deposition. This is probably the first report that traumatic mating reduces female remating duration through successive remating experiments in animals. Overall, our results provide evidence that traumatic mating in the scorpionfly helps increase the male's anchoring control during mating and provides him advantage in sperm competition, but at the expense of lowering female fecundity.The cost-benefit ratio of group living is thought to vary with group size individuals in 'optimally sized' groups should have higher fitness than individuals in groups that are either too large or too small. However, the relationship between group size and individual fitness has been difficult to establish for long-lived species where the number of groups studied is typically quite low. Here, we present evidence for optimal group size that maximizes female fitness in a population of geladas (Theropithecus gelada). Drawing on 14 years of demographic data, we found that females in small groups experienced the highest death rates, while females in mid-sized groups exhibited the highest reproductive performance. This group size effect on female reproductive performance was largely explained by variation in infant mortality (and, in particular, by infanticide from immigrant males) but not by variation in reproductive rates. Taken together, females in mid-sized groups are projected to attain optimal fitness due to conspecific infanticide and, potentially, predation. Our findings provide insight into how and why group size shapes fitness in long-lived species.While the fundamental biophysics of C3 photosynthesis is highly conserved across plants, substantial leaf structural and enzymatic variation translates into variability in rates of carbon assimilation. Although this variation is well documented, it remains poorly understood how photosynthetic rates evolve, and whether macroevolutionary changes are related to the evolution of leaf morphology and biochemistry. A substantial challenge in large-scale comparative studies is disentangling evolutionary adaptation from environmental acclimation. Selleckchem Ibrutinib We overcome this by using a 'macroevolutionary common garden' approach in which we measured metabolic traits (Jmax and Vcmax) from 111 phylogenetically diverse species in a shared environment. We find substantial phylogenetic signal in these traits at moderate phylogenetic timescales, but this signal dissipates quickly at deeper scales. Morphological traits exhibit phylogenetic signal over much deeper timescales, suggesting that these are less evolutionarily constrained than metabolic traits. Furthermore, while morphological and biochemical traits (LMA, Narea and Carea) are weakly predictive of Jmax and Vcmax, evolutionary changes in these traits are mostly decoupled from changes in metabolic traits. This lack of tight evolutionary coupling implies that it may be incorrect to use changes in these functional traits in response to global change to infer that photosynthetic strategy is also evolving.It has been suggested that the human species may be undergoing an evolutionary transition in individuality (ETI). But there is disagreement about how to apply the ETI framework to our species, and whether culture is implicated as either cause or consequence. Long-term gene-culture coevolution (GCC) is also poorly understood. Some have argued that culture steers human evolution, while others proposed that genes hold culture on a leash. We review the literature and evidence on long-term GCC in humans and find a set of common themes. First, culture appears to hold greater adaptive potential than genetic inheritance and is probably driving human evolution. The evolutionary impact of culture occurs mainly through culturally organized groups, which have come to dominate human affairs in recent millennia. Second, the role of culture appears to be growing, increasingly bypassing genetic evolution and weakening genetic adaptive potential. Taken together, these findings suggest that human long-term GCC is characterized by an evolutionary transition in inheritance (from genes to culture) which entails a transition in individuality (from genetic individual to cultural group).