Colour has many different functions in animals, such as an involvement in thermoregulation, crypsis, and social interactions. Species capable of physiological colour change may alter their coloration in response to ecological conditions. The Moorish gecko, Tarentola mauritanica, is capable of actively changing its body coloration. In the present study, we investigated colour change in this gecko as a function of background, temperature, and light. Our results demonstrate that the Moorish gecko indeed changes its dorsal colour in response to changes in environmental conditions. By contrast to several other reptilian species, this rapid colour change does not appear to be associated with thermoregulation. Background matching, however, did appear to be a prominent function, although illumination appears to be an essential trigger. Future research should concentrate on individual variation and its effectiveness with respect to antipredatory mechanisms. physiological color change in Sceloporus occidentalis by epinephrine. Copeia 2: 341-342. Cuthill IC, Bennett ATD, Partridge JC, Maier EJ. 1999. Plumage reflectance and the objective assessment of avian sexual dichromatism. American Naturalist 160: 183-200. De Jong PW, Gussekloo WS, Brakefield PM. 1996. Differences in thermal balance, body temperature and activity between non-melanic and melanic two-spot ladybird beetles (Adalia bipunctata) under controlled conditions. Journal of Experimental Biology 199: 2655-2666. Endler JA. 1978. A predator's view of animal color patterns. Evolutionary Biology 11: 319-364. Endler JA. 1980. Natural selection on color patterns in Poecilia reticulata. Evolution 34: 76-91. Fields PG, McNeil JN. 1988. The importance of seasonal variation in hair coloration for thermoregulation of Ctenucha virginica larvae (Lepidoptera: Arctiidae). Physiological Entomology 13: 165-175. Forsman A. 1995. Heating rates and body temperature variation in melanistic and zigzag Vipera berus: does colour make a difference? Annales Zoologici Fennici 32: 365-374. Garcia TS, Straus R, Sih A. 2003. Temperature and ontogenetic effects on color change in the larval salamander species Ambystoma barbouri and Abystoma texanum. Canadian Journal of Zoology 81: 710-715. Germano DJ, Williams DF. 2007. Ontogenetic and seasonal changes in coloration of the blunt-nosed leopard lizard (Gambelia sila). The Southwestern Naturalist 52: 46-53. Gibson R, Falls JB. 1979. Thermal biology of the common garter snake Thamnophis sirtalis (L.). II. The effects of melanism. Oecologia 43: 99-109. Gibsons JRH, Lillywhite HB. 1981. Ecological segregation, color matching, and speciation in lizards of the Amphibolurus decresii species complex (Lacertilia: Agamidae). Ecology 62: 1572-1584. Gil MJ, Pérez-Mellado V, Guerrero F. 1993. Eine vegleichende Studie des Nahrungserwebs von Tarentola mauritanica (Reptilia: Gekkonidae) in Habitaten auf dem Festland und auf Inseln. Sauria 15: 9-17. Greenberg B, Noble GK. 1944. Social behavior of the American chameleon (Anolis carolinensis Voight). Physiological Z...

BackgroundThis article examines the use of a novel nano-system, gold nanoparticles coated with indolicidin (AuNPs–indolicidin), against pathogenic Candida albicans biofilms. Candida species cause frequent infections owing to their ability to form biofilms, primarily on implant devices.Materials and methodsWe used an integrated approach, evaluating the effect of AuNPs-indolicidin on prevention and eradication of Candida biofilms formed in multi-well polystyrene plates, with relative gene expression assays. Four biofilm-associated genes (FG1, HWP1, ALS1 and ALS3, and CDR1 and CDR2) involved in efflux pump were analyzed using reverse transcription polymerase chain reaction.ResultsTreatment with the nano-complex significantly inhibits the capacity of C. albicans to form biofilms and impairs preformed mature biofilms. Treatment with AuNPs–indolicidin results in an increase in the kinetics of Rhodamine 6G efflux and a reduction in the expression of biofilm-related genes.ConclusionThese data provide a chance to develop novel therapies against nosocomially acquired refractory C. albicans biofilms.

Artificial selection affects phenotypes differently by natural selection. Domestic traits, which pass into the wild, are usually negatively selected. Yet, exceptionally, this axiom may fail to apply if genes, from the domestic animals, increase fertility in the wild. We studied a rare case of a wild boar population under the framework of Wright's interdemic selection model, which could explain gene flow between wild boar and pig, both considered as demes. We analysed the MC1R gene and microsatellite neutral loci in 62 pregnant wild boars as markers of hybridization, and we correlated nucleotide mutations on MC1R (which are common in domestic breeds) to litter size, as an evaluation of fitness in wild sow. Regardless of body size and phyletic effects, wild boar sows bearing nonsynonymous MC1R mutations produced larger litters. This directly suggests that artificially selected traits reaching wild populations, through interdemic gene flow, could bypass natural selection if and only if they increase the fitness in the wild.

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Unpredictable environmental conditions and highly fluctuating population densities are believed to have produced a ‘reversed island syndrome’ (RIS) in an insular population of the Wall lizard on Licosa Islet, Italy. Several of the physiological, behavioural, and life‐history changes that constitute the RIS could result from positive selection on increased activity of melanocortins. For example, increased levels of α‐melanocyte‐stimulating hormone (MSH) should lead to increased investment in reproduction and increased immunocompetence in the island population. We tested the crucial assumption of this idea that plasma levels of α‐MSH in Licosa Islet lizards are elevated compared to those of the mainland relatives. We also tested for differences in reproductive effort between populations, by measuring plasma levels of 5‐α‐dihydrotestosterone in males and clutch mass in females. In addition, we assessed ectoparasite load as an indicator for the lizards’ resistance to environmental stress. In agreement with the RIS, we found that insular lizards exhibit higher α‐MSH levels, allocate more energy to reproduction, and have a reduced ectoparasite load compared to the nearest mainland population. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ●●, ●●–●●.