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Author (up) Alcock, J.; Maley, C.C.; Aktipis, C.A. file  url
  Title Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms Type Journal Article
  Year 2014 Publication BioEssays : News and Reviews in Molecular, Cellular and Developmental Biology Abbreviated Journal Bioessays  
  Volume 36 Issue 10 Pages 940-949  
  Keywords Animals; *Biological Evolution; *Feeding Behavior; Gastrointestinal Tract/*microbiology; Humans; *Microbiota; Models, Biological; Obesity/etiology; Cravings; Evolutionary conflict; Host manipulation; Microbiome; Obesity  
  Abstract Microbes in the gastrointestinal tract are under selective pressure to manipulate host eating behavior to increase their fitness, sometimes at the expense of host fitness. Microbes may do this through two potential strategies: (i) generating cravings for foods that they specialize on or foods that suppress their competitors, or (ii) inducing dysphoria until we eat foods that enhance their fitness. We review several potential mechanisms for microbial control over eating behavior including microbial influence on reward and satiety pathways, production of toxins that alter mood, changes to receptors including taste receptors, and hijacking of the vagus nerve, the neural axis between the gut and the brain. We also review the evidence for alternative explanations for cravings and unhealthy eating behavior. Because microbiota are easily manipulatable by prebiotics, probiotics, antibiotics, fecal transplants, and dietary changes, altering our microbiota offers a tractable approach to otherwise intractable problems of obesity and unhealthy eating.  
  Call Number Serial 2002  
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Author (up) Delattre, M.; Felix, M.A. file  url
  Title Microevolutionary studies in nematodes: a beginning Type Journal Article
  Year 2001 Publication BioEssays : News and Reviews in Molecular, Cellular and Developmental Biology Abbreviated Journal Bioessays  
  Volume 23 Issue 9 Pages 807-819  
  Keywords Animals; *Biological Evolution; Caenorhabditis elegans/genetics; Drosophila/genetics; Genetic Techniques; Genetic Variation; Genotype; Mutagenesis; Nematoda/*classification/*genetics; *Polymorphism, Genetic  
  Abstract Comparisons between related species often allow the detailed genetic analysis of evolutionary processes. Here we advocate the use of the nematode Caenorhabditis elegans (and several other rhabditid species) as model systems for microevolutionary studies. Compared to Drosophila species, which have been a mainstay of such studies, C. elegans has a self-fertilizing mode of reproduction, a shorter life cycle and a convenient cell-level analysis of phenotypic variation. Data concerning its population genetics and ecology are still scarce, however. We review molecular, behavioral and developmental intraspecific polymorphisms for populations of C. elegans, Oscheius sp. 1 and Pristionchus pacificus. Focusing on vulval development, which has been well characterized in several species, we discuss relationships between patterns of variations: (1) for a given genotype (developmental variants), (2) after mutagenesis (mutability), (3) in different populations of the same species (polymorphisms) and (4) between closely related species. These studies have revealed that evolutionary variations between sister species affect those characters that show phenotypic developmental variants, that are mutable and that are polymorphic within species.  
  Call Number Serial 1024  
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Author (up) Griffin, A.S.; West, S.A.; Buckling, A. file  url
  Title Cooperation and competition in pathogenic bacteria Type Journal Article
  Year 2004 Publication Nature Abbreviated Journal Nature  
  Volume 430 Issue 7003 Pages 1024-1027  
  Keywords Altruism; Analysis of Variance; *Biological Evolution; Competitive Behavior; Cooperative Behavior; Host-Parasite Interactions; Humans; *Models, Biological; Pseudomonas aeruginosa/classification/genetics/*pathogenicity/*physiology; Siderophores/*biosynthesis; Virulence  
  Abstract Explaining altruistic cooperation is one of the greatest challenges for evolutionary biology. One solution to this problem is if costly cooperative behaviours are directed towards relatives. This idea of kin selection has been hugely influential and applied widely from microorganisms to vertebrates. However, a problem arises if there is local competition for resources, because this leads to competition between relatives, reducing selection for cooperation. Here we use an experimental evolution approach to test the effect of the scale of competition, and how it interacts with relatedness. The cooperative trait that we examine is the production of siderophores, iron-scavenging agents, in the pathogenic bacterium Pseudomonas aeruginosa. As expected, our results show that higher levels of cooperative siderophore production evolve in the higher relatedness treatments. However, our results also show that more local competition selects for lower levels of siderophore production and that there is a significant interaction between relatedness and the scale of competition, with relatedness having less effect when the scale of competition is more local. More generally, the scale of competition is likely to be of particular importance for the evolution of cooperation in microorganisms, and also the virulence of pathogenic microorganisms, because cooperative traits such as siderophore production have an important role in determining virulence.  
  Call Number Serial 1552  
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Author (up) Mori, N.; Mori, M. file  url
doi  openurl
  Title Neuronal Shc: a gene of longevity in the brain? Type Journal Article
  Year 2011 Publication Medical Hypotheses Abbreviated Journal Med Hypotheses  
  Volume 77 Issue 6 Pages 996-999  
  Keywords Animals; *Biological Evolution; Brain/*metabolism; Brain-Derived Neurotrophic Factor/metabolism; Humans; *Longevity; Mammals/genetics/*physiology; N-Methylaspartate/metabolism; Neurons/*metabolism; Quality of Life; Shc Signaling Adaptor Proteins/*metabolism  
  Abstract Aging is inevitable to all multi-cellular organisms, and each organism has its own lifespan. The species-specific lifespan seems determined genetically; however little is known about how the lifespan determined. During the last decades accumulative evidence indicates that there is certainly a set of genes that are involved in the lifespan determination. Among those dozens of genes, the Shc gene encoding a phosphotyrosine signal adaptor is of potential interests in mammalian aging and/or longevity determination. Shc is merely one form of a gene family, and accumulative evidence demonstrates the presence of additional Shc homologues that are strongly expressed in the nervous system. We hypothesize that lifespan is regulated primarily by the nervous system and/or brain, and neurally expressed Shc homologues play pivotal roles in relation to the evolution of longevity with quality of life. We discuss herein the recent progress of our understanding of the neuronally expressed Shc genes in comparision with p66-Shc as a candidate for the evolution of long life with higher quality of life in mammals.  
  Call Number Serial 109  
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Author (up) Root, T.L.; Price, J.T.; Hall, K.R.; Schneider, S.H.; Rosenzweig, C.; Pounds, J.A. file  url
doi  openurl
  Title Fingerprints of global warming on wild animals and plants Type Journal Article
  Year 2003 Publication Nature Abbreviated Journal Nature  
  Volume 421 Issue 6918 Pages 57-60  
  Keywords Animals; Animals, Wild/*physiology; Bias (Epidemiology); *Biological Evolution; *Ecosystem; *Greenhouse Effect; *Plant Physiological Phenomena; Temperature; Time Factors  
  Abstract Over the past 100 years, the global average temperature has increased by approximately 0.6 degrees C and is projected to continue to rise at a rapid rate. Although species have responded to climatic changes throughout their evolutionary history, a primary concern for wild species and their ecosystems is this rapid rate of change. We gathered information on species and global warming from 143 studies for our meta-analyses. These analyses reveal a consistent temperature-related shift, or 'fingerprint', in species ranging from molluscs to mammals and from grasses to trees. Indeed, more than 80% of the species that show changes are shifting in the direction expected on the basis of known physiological constraints of species. Consequently, the balance of evidence from these studies strongly suggests that a significant impact of global warming is already discernible in animal and plant populations. The synergism of rapid temperature rise and other stresses, in particular habitat destruction, could easily disrupt the connectedness among species and lead to a reformulation of species communities, reflecting differential changes in species, and to numerous extirpations and possibly extinctions.  
  Call Number Serial 175  
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Author (up) Simon, A.; Tanaka, E.M. file  url
doi  openurl
  Title Limb regeneration Type Journal Article
  Year 2013 Publication Wiley Interdisciplinary Reviews. Developmental Biology Abbreviated Journal Wiley Interdiscip Rev Dev Biol  
  Volume 2 Issue 2 Pages 291-300  
  Keywords Ambystoma mexicanum/growth & development; Animals; *Biological Evolution; Extremities/*growth & development; Ranidae/growth & development; Regeneration/*genetics/physiology; Salamandridae/growth & development  
  Abstract Limb regeneration is observed in certain members of the animal phyla. Some animals keep this ability during their entire life while others lose it at some time during development. How do animals regenerate limbs? Is it possible to find unifying, conserved mechanisms of limb regeneration or have different species evolved distinct means of replacing a lost limb? How is limb regeneration similar or different to limb development? Studies on many organisms, including echinoderms, arthropods, and chordates have provided significant knowledge about limb regeneration. In this focus article, we concentrate on tetrapod limb regeneration as studied in three model amphibians: newts, axolotls, and frogs. We review recent progress on tissue interactions during limb regeneration, and place those findings into an evolutionary context.  
  Call Number Serial 1096  
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Author (up) Wilkinson, D.M.; Ruxton, G.D. file  url
  Title Understanding selection for long necks in different taxa Type Journal Article
  Year 2012 Publication Biological Reviews of the Cambridge Philosophical Society Abbreviated Journal Biol Rev Camb Philos Soc  
  Volume 87 Issue 3 Pages 616-630  
  Keywords Animals; *Biological Evolution; Extremities/anatomy & histology; *Feeding Behavior; Neck/*anatomy & histology  
  Abstract There has been recent discussion about the evolutionary pressures underlying the long necks of extant giraffes and extinct sauropod dinosaurs. Here we summarise these debates and place them in a wider taxonomic context. We consider the evolution of long necks across a wide range of (both living and extinct) taxa and ask whether there has been a common selective factor or whether each case has a separate explanation. We conclude that in most cases long necks can be explained in terms of foraging requirements, and that alternative explanations in terms of sexual selection, thermoregulation and predation pressure are not as well supported. Specifically, in giraffe, tortoises, and perhaps sauropods there is likely to have been selection for high browsing. It the last case there may also have been selection for reaching otherwise inaccessible aquatic plants or for increasing the energetic efficiency of low browsing. For camels, wading birds and ratites, original selection was likely for increased leg length, with correlated selection for a longer neck to allow feeding and drinking at or near substrate level. For fish-eating long-necked birds and plesiosaurs a small head at the end of a long neck allows fast acceleration of the mouth to allow capture of elusive prey. A swan's long neck allows access to benthic vegetation, for vultures the long neck allows reaching deep into a carcass. Geese may be an unusual case where anti-predator vigilance is important, but so may be energetically efficient low browsing. The one group for which we feel unable to draw firm conclusions are the pterosaurs, this is in keeping with the current uncertainty about the biology of this group. Despite foraging emerging as a dominant theme in selection for long necks, for almost every taxonomic group we have identified useful empirical work that would increase understanding of the selective costs and benefits of a long neck.  
  Call Number Serial 1599  
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