Since the Eocene, the diversity of artiodactyls has increased while that of perissodactyls has decreased. Reasons given for this contrasting pattern are that the evolution of a ruminant digestive tract and improved locomotion in artiodactyls were adaptively advantageous in the highly seasonal post-Eocene climate. We suggest that evolution of a carotid rete, a structure highly developed in artiodactyls but absent in perissodactyls, was at least as important. The rete confers an ability to regulate brain temperature independently of body temperature. The net effect is that in hot ambient conditions artiodactyls are able to conserve energy and water, and in cold ambient conditions they are able to conserve body temperature. In perissodactyls, brain and body temperature change in parallel and thermoregulation requires abundant food and water to warm/cool the body. Consequently, perissodactyls occupy habitats of low seasonality and rich in food and water, such as tropical forests. Conversely, the increased thermoregulatory flexibility of artiodactyls has facilitated invasion of new adaptive zones ranging from the Arctic Circle to deserts and tropical savannahs.
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http://dx.doi.org/10.1098/rsbl.2008.0138 | DOI Listing |
Cytokine
January 2025
Department of Gastroenterology, General Hospital of Ningxia Medical University (The First Clinical Medical College of Ningxia Medical University), 750004 Yinchuan, China.
Background: Sepsis is an infection-related systemic inflammation with high mortality rates. Activation of formyl peptide receptor 1 (FPR1) in immune cells can promote their chemotaxis and inflammatory response, which imbalances immune response during the process of sepsis. FPR1 blockade did diminish systemic inflammatory response during bacterial infection.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
Maintaining human body temperature in both high and low-temperature environments is fundamental to human survival, necessitating high-performance thermal insulation materials to prevent heat exchange with the external environment. Currently, most fibrous thermal insulation materials are characterized by large weight, suboptimal thermal insulation, and inferior mechanical and waterproof performance, thereby limiting their effectiveness in providing thermal protection for the human body. In this study, lightweight, waterproof, mechanically robust, and thermal insulating polyamide-imide (PAI) grooved micro/nanofibrous aerogels were efficiently and directly assembled by electrospinning.
View Article and Find Full Text PDFIntegr Environ Assess Manag
January 2025
Faculty of Fine Arts, Design and Architecture Department of Landscape Architecture, Tekirdağ Namık Kemal University, Tekirdağ, Türkiye.
Wetlands provide necessary ecosystem services, such as climate regulation and contribution to biodiversity at global and local scales, and they face spatial changes due to natural and anthropogenic factors. The degradation of the characteristic structure signals potential severe threats to biodiversity. This study aimed to monitor the long-term spatial changes of the Göksu Delta, a critical Ramsar site, using remote sensing techniques.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Duke University, Department of Physics, Durham, North Carolina 27708, USA.
The emergence of a quantum spin liquid (QSL), a state of matter that can result when electron spins are highly correlated but do not become ordered, has been the subject of a considerable body of research in condensed matter physics [1,2]. Spin liquid states have been proposed as hosts for high-temperature superconductivity [3] and can host topological properties with potential applications in quantum information science [4]. The excitations of most quantum spin liquids are not conventional spin waves but rather quasiparticles known as spinons, whose existence is well established experimentally only in one-dimensional systems; the unambiguous experimental realization of QSL behavior in higher dimensions remains challenging.
View Article and Find Full Text PDFElectromagn Biol Med
January 2025
Department of Mathematics, University of Gour Banga, Malda, India.
In cardiovascular research, electromagnetic fields generated by Riga plates are utilized to study or manipulate blood flow dynamics, which is particularly crucial in developing treatments for conditions such as arterial plaque deposition and understanding blood behavior under varied flow conditions. This research predicts the flow patterns of blood enhanced with gold and maghemite nanoparticles (gold-maghemite/blood) in an electromagnetic microchannel influenced by Riga plates with a temperature gradient that decays exponentially, under sudden changes in pressure gradient. The flow modeling includes key physical influences like radiation heat emission and Darcy drag forces in porous media, with the flow mathematically represented through unsteady partial differential equations solved using the Laplace transform (LT) method.
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