Maximum lifespan in birds and mammals varies strongly with body mass such that large species tend to live longer than smaller species. However, many species live far longer than expected given their body mass. This may reflect interspecific variation in extrinsic mortality, as life-history theory predicts investment in long-term survival is under positive selection when extrinsic mortality is reduced. Here, we investigate how multiple ecological and mode-of-life traits that should reduce extrinsic mortality (including volancy (flight capability), activity period, foraging environment and fossoriality), simultaneously influence lifespan across endotherms. Using novel phylogenetic comparative analyses and to our knowledge, the most species analysed to date (n ¼ 1368), we show that, over and above the effect of body mass, the most important factor enabling longer lifespan is the ability to fly. Within volant species, lifespan depended upon when (day, night, dusk or dawn), but not where (in the air, in trees or on the ground), species are active. However, the opposite was true for non-volant species, where lifespan correlated positively with both arboreality and fossoriality. Our results highlight that when studying the molecular basis behind cellular processes such as those underlying lifespan, it is important to consider the ecological selection pressures that shaped them over evolutionary time.

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Stable isotope mixing models (SIMMs) are an important tool used to study species' trophic ecology. These models are dependent on, and sensitive to, the choice of trophic discrimination factors (TDF) representing the offset in stable isotope delta values between a consumer and their food source when they are at equilibrium. Ideally, controlled feeding trials should be conducted to determine the appropriate TDF for each consumer, tissue type, food source, and isotope combination used in a study. In reality however, this is often not feasible nor practical. In the absence of species-specific information, many researchers either default to an average TDF value for the major taxonomic group of their consumer, or they choose the nearest phylogenetic neighbour for which a TDF is available. Here, we present the SIDER package for R, which uses a phylogenetic regression model based on a compiled dataset to impute (estimate) a TDF of a consumer. We apply information on the tissue type and feeding ecology of the consumer, all of which are known to affect TDFs, using Bayesian inference. Presently, our approach can estimate TDFs for two commonly used isotopes (nitrogen and carbon), for species of mammals and birds with or without previous TDF information. The estimated posterior probability provides both a mean and variance, reflecting the uncertainty of the estimate, and can be subsequently used in the current suite of SIMM software. SIDER allows users to place a greater degree of confidence on their choice of TDF and its associated uncertainty, thereby leading to more robust predictions about trophic relationships in cases where study-specific data from feeding trials is unavailable. The underlying database can be updated readily to incorporate more stable isotope tracers, replicates and taxonomic groups to further increase the confidence in dietary estimates from stable isotope mixing models, as this information becomes available.

Observations highlight the complex tectonic, magmatic, and geodynamic phases of the Cenozoic post-collisional evolution of the Himalayan-Tibetan orogen and show that these phases migrate erratically among terranes accreted to Asia prior to the Indian collision. This behavior contrasts sharply with the expected evolution of large, hot orogens formed by collision of lithospheres with laterally uniform properties. Motivated by this problem, we use two-dimensional numerical geodynamical model experiments to show that the enigmatic behavior of the Himalayan-Tibetan orogeny can result from crust-mantle decoupling, transport of crust relative to the mantle lithosphere, and diverse styles of lithospheric mantle delamination, which emerge self-consistently as phases in the evolution of the system. These model styles are explained by contrasting inherited mantle lithosphere properties of the Asian upper-plate accreted terranes. Deformation and lithospheric delamination preferentially localize in terranes with the most dense and weak mantle lithosphere, first in the Qiangtang and then in the Lhasa mantle lithospheres. The model results are shown to be consistent with 11 observed complexities in the evolution of the Himalayan-Tibetan orogen. The broad implication is that all large orogens containing previously accreted terranes are expected to have an idiosyncratic evolution determined by the properties of these terranes, and will be shown to deviate from predictions of uniform lithosphere models.

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36Many collisional orogens contain exotic terranes that were accreted to either the 37 subducting or overriding plate prior to terminal continent-continent collision. The ways in 38 which the physical properties of these terranes influence collision remain poorly 39 understood. We use 2D thermomechanical finite element models to examine the effects of prior 'soft' terrane accretion to a continental upper plate (retro-lithosphere) on the ensuing continent-continent collision. The experiments explore how the style of collision changes in 2 40 41 42 response to variations in the density and viscosity of the accreted terrane lithospheric 43 mantle, as well as the density of the pro-lithospheric mantle, which determines its 44 propensity to subduct or compress the accreted terrane and retro-lithosphere. The models 45 evolve self-consistently through several emergent phases: breakoff of subducted oceanic 46 lithosphere; pro-continent subduction; shortening of the retro-lithosphere accreted 47 terrane, sometimes accompanied by lithospheric delamination; and, terminal 48 underthrusting of pro-lithospheric mantle beneath the accreted terrane crust or mantle. 49 The modeled variations in the properties of the accreted terrane lithospheric mantle can be 50 interpreted to reflect metasomatism during earlier oceanic subduction beneath the terrane. 51 Strongly metasomatized (i.e., dense and weak) mantle is easily removed by delamination or 52 entrainment by the subducting pro-lithosphere, and facilitates later flat-slab 53 underthrusting. The models are a prototype representation of the Himalayan-Tibetan 54 orogeny in which there is only one accreted terrane, representing the Lhasa terrane, but 55 they nonetheless exhibit processes like those inferred for the more complex Himalayan-56 Tibetan system. Present-day underthrusting of the Tibetan Plateau crust by Indian mantle 57 lithosphere requires that the Lhasa terrane lithospheric mantle has been removed. Some of 58 the model results support previous conceptual interpretations that Tibetan lithospheric 59 mantle was removed by convective coupling to the pro-lithosphere. They can also be 60 interpreted to suggest that delamination beneath Tibet was facilitated by densification and 61 weakening of the plateau lithosphere, perhaps owing to long-lived pre-to syn-collisional 62 subduction-related metasomatism beneath the Asian margin.63 64

1. Bird species are declining across Europe. Current European policy, that is, the Birds and Habitats Directives, focus on habitat management as a way of halting the declines. This paper explores the role of predation in causing bird population declines and asks if we need to reconsider our approach to the management of generalist predators. 2. We analysed bird population trends and distribution changes across Europe, Britain and Ireland, reflecting an increasing gradient of generalist predator abundance (principally red fox Vulpes vulpes and species of the family Corvidae). We tested if ground-nesting bird species, considered more vulnerable to predation, were in greater decline compared to other nesting strategies. We also compared Annex I designated species to non-designated species as a proxy for habitat management. 3. We found that across Europe, 74% of ground-nesting bird species were in decline, compared to 41% of other species. This was especially evident in Britain, where the pattern was 66% compared to 31%, and in Ireland, 71% compared to 20%. Ground-nesting species were significantly more likely to be declining than other species. 4. These patterns are consistent with the idea that population declines are at least partially related to the increased abundance of generalist predators. In Britain, ground-nesting species were less likely to be in decline if covered by Annex I designation. However, in Europe and Ireland, Annex I status did not mitigate the effect of nesting strategy. 5. Policy implications. Current legislation is clearly insufficient to prevent widespread declines in ground-nesting birds, and this is the case across Europe, in Britain and Ireland. Ignoring the role of generalist predators in modern landscapes may lead to further declines and losses. We urgently need large-scale experiments to establish causality in the impact of generalist predators on ground-nesting birds in different landscapes. If we value our ground-nesting bird species, consideration needs to be given to the control of widespread generalist predators, at least until landscapes are restored.

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