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Aim Species are responding to climate warming by shifting their distributions toward historically cooler regions, but the degree to which expansions at cool range limits are balanced by contractions at warm limits is unknown. We synthesized published data documenting shifts at species’ warm versus cool range limits along elevational gradients to (a) test classic ecological theory that predicts temperature more directly influences species’ cool range limits than their warm range limits, and (b) determine how warming‐associated shifts have changed the extent and area of species’ elevational distributions. Location Global. Time period 1802–2012. Major taxa studied Vascular plants, endotherms, ectotherms. Methods We compiled a dataset of 975 species from 32 elevational gradients for which range shifts have been measured at both warm and cool range limits. We compared the magnitude and variance of shifts at species’ warm versus cool limits, and quantified how range shifts have impacted species’ elevational extents and areas. Results On average species have shifted upslope associated with temperature increases at both warm and cool limits (warm limit: 92 ± 455 m/C; cool limit: 131 ± 465 m/C; overall mean ± SD). There was no systematic difference in the magnitude or variance of shifts at warm versus cool limits and thus no indication that cool limits are more directly controlled by temperature. Species’ elevational extents and available area significantly decreased for mountaintop species. Main conclusions Our results do not support the long‐standing hypothesis that cool limits are more sensitive or responsive to temperature. We find that, across the globe, mountaintop species’ ranges are significantly shrinking as they shift upslope, supporting predictions that high elevation species are especially vulnerable to temperature increases. Our synthesis highlights the extreme variation in species’ distributional responses to warming, which may indicate that biotic interactions play a more prominent role in setting range limits than previously thought.

As global temperatures reach record highs, threats posed by climate change to biodiversity become ever more severe. For endotherms, maintaining body temperature within safe bounds is fundamental for performance and survival. Animals routinely modify their behavior to buffer physiological impacts of high temperatures (eg ceasing activity, seeking shade). However, this can impose substantial costs related to missed opportunities to engage in other important activities, with potentially large but often overlooked consequences for survival and reproduction. Here, we outline behavioral trade-offs birds and mammals face in navigating thermal landscapes and associated challenges of balancing energy, water, and time budgets; review the rapidly expanding knowledge in this field; and summarize examples – across taxa – of fitness costs during hot weather. We argue that a shift is needed in evaluating the impacts of heat on birds and mammals, and that fitness costs of missed opportunities must be explicitly integrated into climate-change vulnerability frameworks.

Many biological surfaces of animals and plants (e.g., bird feathers, insect wings, plant leaves, etc.) are superhydrophobic with rough surfaces at different length scales. Previous studies have focused on a simple drop-bouncing behavior on biological surfaces with low-speed impacts. However, we observed that an impacting drop at high speeds exhibits more complicated dynamics with unexpected shock-like patterns: Hundreds of shock-like waves are formed on the spreading drop, and the drop is then abruptly fragmented along with multiple nucleating holes. Such drop dynamics result in the rapid retraction of the spreading drop and thereby a more than twofold decrease in contact time. Our results may shed light on potential biological advantages of hypothermia risk reduction for endothermic animals and spore spreading enhancement for fungi via wave-induced drop fragmentation.

Endothermy, i.e. the endogenous production of metabolic heat, has evolved multiple times among vertebrates, and several strategies of heat production have been studied extensively by physiologists over the course of the twentieth century. The independent acquisition of endothermy by mammals and birds has been the subject of many hypotheses regarding their origin and associated evolutionary constraints. Many groups of vertebrates, however, are thought to possess other mechanisms of heat production, and alternative ways to regulate thermogenesis that are not always considered in the palaeontological literature. Here, we perform a review of the mechanisms involved in heat production, with a focus on cellular and molecular mechanisms, in a phylogenetic context encompassing the entire vertebrate diversity. We show that endothermy in mammals and birds is not as well defined as commonly assumed by evolutionary biologists and consists of a vast array of physiological strategies, many of which are currently unknown. We also describe strategies found in other vertebrates, which may not always be considered endothermy, but nonetheless correspond to a process of active thermogenesis. We conclude that endothermy is a highly plastic character in vertebrates and provides a guideline on terminology and occurrences of the different types of heat production in vertebrate evolution. This article is part of the theme issue ‘Vertebrate palaeophysiology’.

This paper presents an up-to-date overview of the various advanced materials as adsorbent used in the recovery of precious metals from wastewater. The precious metals concentrated here include gold, silver, palladium and platinum, whose recovery is interesting mainly due to their vast industrial applications and high market prices. Among various methods, adsorption approach is one of the most efficient techniques for the recovery of precious metal ions from aqueous solutions. There are a number of absorbents such as carbon materials, metal-organic frameworks (MOFs), biopolymers, silicas, resins, and transition-metal sulfides, which have been developed and explored to efficient recovery of precious metal ions from wastewater. Thermodynamics and kinetics were further discussed for exploring the adsorption mechanism of precious metal ions in these advanced materials. It was found that the adsorption process of these metals is mostly spontaneous (ΔG < 0) and endothermic (ΔH > 0) in nature. This review would contribute to the development of advanced materials for recovery of precious metals from secondary sources such as wastewater.

A pH-sensitive chitosan/sepiolite clay/algae biocomposite (Chi/Sep/Alg) was fabricated to remove cationic (malachite green, MG) and anionic (remazol brilliant blue R, RBBR) dyes from aqueous. The characteristics of Chi/Sep/Alg biocomposite were investigated by pHpzc, pH-potentiometric titration, CHNS, XRD, SEM–EDX, FTIR, and BET analyses. A Box–Behnken design (BBD) was adopted to optimize the adsorptive performance of the Chi/Sep/Alg biocomposite towards removal of MG and RBBR dyes using three controllable operating factors, namely Chi/Sep/Alg dose (0.02–0.1 g), solution pH (4–8), and process time (5–30 min). The ideal BBD model circumstances for MG dye removal efficiency were as follows: Chi/Sep/Alg dose (0.1 g/L), solution pH 8, and time (17.5 min), while for RBBR dye, the ideal circumstances were Chi/Sep/Alg dose (0.1 g/L), pH ~ 4, and time (17.5 min). The adsorption kinetic and isotherm reflect that the adsorption of MG and RBBR dyes onto Chi/Sep/Alg biocomposite obeyed pseudo-second-order and Freundlich isotherm model, respectively. The maximum adsorption capacities of Chi/Sep/Alg biocomposite towards MG (515.7 mg/g) at basic pH environment (pH 8) and RBBR (292.4 mg/g) at acidic pH environment (pH 4). An endothermic and spontaneous adsorption process of MG and RBBR dyes was confirmed by the calculated thermodynamic functions. The adsorption mechanism of MG and RBBR dyes on the surface of Chi/Sep/Alg biocomposite can be attributed to various interactions such as electrostatic, H-bonding, and n-π interactions. Thus, this pH-sensitive Chi/Sep/Alg biocomposite exhibits a great affinity towards capturing cationic and anionic dyes by adjusting the solution pH.

Recent discoveries of spectacular dinosaur fossils overwhelmingly support the hypothesis that birds are descended from maniraptoran theropod dinosaurs, and furthermore, demonstrate that distinctive bird characteristics such as feathers, flight, endothermic physiology, unique strategies for reproduction and growth, and a novel pulmonary system originated among Mesozoic terrestrial dinosaurs. The transition from ground-living to flight-capable theropod dinosaurs now probably represents one of the best-documented major evolutionary transitions in life history. Recent studies in developmental biology and other disciplines provide additional insights into how bird characteristics originated and evolved. The iconic features of extant birds for the most part evolved in a gradual and stepwise fashion throughout archosaur evolution. However, new data also highlight occasional bursts of morphological novelty at certain stages particularly close to the origin of birds and an unavoidable complex, mosaic evolutionary distribution of major bird characteristics on the theropod tree. Research into bird origins provides a premier example of how paleontological and neontological data can interact to reveal the complexity of major innovations, to answer key evolutionary questions, and to lead to new research directions. A better understanding of bird origins requires multifaceted and integrative approaches, yet fossils necessarily provide the final test of any evolutionary model. Research on the origin and evolution of birds has gathered pace in recent years, aided by a continuous stream of new fossil finds as well as molecular phylogenies. Bird origins, in particular, are now better understood than those of mammals, for which the early fossil record is relatively poor compared with that of birds. Xu et al. review progress in tracing the origins of birds from theropod dinosaurs, focusing especially on recent fossil finds of feathered dinosaurs of northeastern China. They integrate current research on developmental biology and functional anatomy with the paleontological record, to show how key features of birds—feathers, wings, and flight—originated and evolved, and radiated from their dinosaur forebears. Science , this issue 10.1126/science.1253293

The chitosan (Ch)—bentonite (B) composite was synthesized and its adsorption properties were investigated for lead ions. The characterization of the Ch-B composite was clarified by FT-IR, SEM, and pzc studies. Factors affecting Pb2+ ion adsorption from aqueous solution; pH, temperature, adsorbent dose, adsorbate concentration, adsorption time, and temperature were examined within the scope of the study. Adsorption was found to increase with increasing pH under acidic conditions, and the adsorbent surface was found to be positive under pH: 5.95. It was found that the adsorption isotherm was suitable for the Langmuir isotherm model and the adsorption capacity from this model was 0.425 mol kg−1. It was observed that the adsorption kinetics fit the PSO and IPD models. Thermodynamic analysis of the adsorption was made and it was determined that the adsorption process was endothermic, with increasing entropy and spontaneous. The reuse conditions of the adsorbent were investigated and it was found that the adsorbed ion was recovered 84% in 0.1 M HCl.

The acquisition of mammalian endothermy is poorly constrained both phylogenetically and temporally. Here, we inferred the resting metabolic rates (RMRs) and the thermometabolic regimes (endothermy or ectothermy) of a sample of eight extinct synapsids using palaeohistology, phylogenetic eigenvector maps (PEMs), and a sample of 17 extant tetrapods of known RMR (quantified using respirometry). We inferred high RMR values and an endothermic metabolism for the anomodonts ( Lystrosaurus sp., Oudenodon bainii ) and low RMR values and an ectothermic metabolism for Clepsydrops collettii, Dimetrodon sp., Edaphosaurus boanerges, Mycterosaurus sp., Ophiacodon uniformis and Sphenacodon sp. A maximum-likelihood ancestral states reconstruction of RMRs performed using the values inferred for extinct synapsids, and the values measured using respirometry in extant tetrapods, shows that the nodes Anomodontia and Mammalia were primitively endotherms. Finally, we performed a parsimony optimization of the presence of endothermy using the results obtained in the present study and those obtained in previous studies that used PEMs. For this, we assigned to each extinct taxon a thermometabolic regime (ectothermy or endothermy) depending on whether the inferred values were significantly higher, lower or not significantly different from the RMR value separating ectotherms from endotherms (1.5 ml O 2 h −1 g −0.67 ). According to this optimization, endothermy arose independently in Archosauromorpha, Sauropterygia and Therapsida. This article is part of the theme issue ‘Vertebrate palaeophysiology’.

Understanding the thermodynamic interactions of cellulose nanomaterials with their environment is important to understand the forces behind their self-organization and co-organisation with other compounds, and to be able to use self-assembly to form new functional multicomponent materials. This review analyzes published studies that determined the thermodynamic parameters of the surface interactions of and adsorption of various compounds (proteins, polymers, and small molecules/ions) onto cellulose nanomaterials. We compiled the data reported and performed a meta-analysis for better comparison and to find trends in the published data. We first introduce the methods employed and describe the adsorption isotherm models typically used to describe the adsorption thermodynamics on nanocellulose surfaces. We then discuss and analyze the published results for the interaction of the various compounds with nanocellulose surfaces. The systems that have been reported on most were adsorption of natural binding proteins and various pollutants from water, such as heavy metal ions, dyes, and drugs. Interactions between cellulose surfaces and the cellulose binding module were generally both enthalpy- and entropy-driven, where the negative binding enthalpy indicates the formation of specific interactions between peptides and the carbohydrate backbone. On the other hand, interactions with charged molecules were mostly endothermic and purely entropy-driven, indicating that the adsorption on nanocellulose surfaces can be described as an interaction between opposite charges, where the entropy increase that arises from the release of surface-structured water molecules and counterions from the electronic double layer supplies the major contribution to the free energy of adsorption. We performed a meta-analysis on all published data, and found a linear relationship between ∆H and ∆S with the slope equal to the reference temperature, irrespective of whether the interacting compound is a specific cellulose binding protein, a non-specific binding protein, a polymer, or a small molecule/ion. This indicates that the process of adsorption is the same for all compounds and takes place with a constant change in Gibbs free energy of interaction, ∆G, where a change in interaction enthalpy is offset by change in entropy change upon binding and vice versa. Graphical abstract