first_imgZebras’ bold striped patterns have puzzled scientists for nearly 150 years. Researchers have offered a lengthy list of possible explanations, from confusing predators by creating a distracting dazzle when a herd gallops away, to helping the animals avoid biting flies. Support for the dazzler hypothesis comes from computer tests using people, who have trouble tracking striped, moving objects on a computer; while other studies have shown that the flies prefer to land on uniformly colored, not striped, surfaces. Now, a team of scientists reports online today in Nature Communications that it has tested these hypotheses—as well as suggestions that the stripes might cool zebras down or make them more attractive to mates—to see which one makes the most ecological sense. The winner: those pesky, blood-sucking, disease-carrying (such as parasitic trypanosomiasis) biting flies. The team discovered that the ranges of the horse fly and tsetse fly species and the three most distinctively striped zebra species (Equus burchelli, E. zebra, and E. grevyi) overlap to a remarkable degree. They did not find a similar ecological match for any of the other hypotheses, not even those involving predators. Instead, the researchers argue that biting flies are the most likely reason that zebras, such as those shown above grazing in Tanzania’s Katavi National Park, evolved their distinctive ornamentation. The insects, they note, harass the equids almost year-round, and are known to torment domesticated horses in these areas. The zebras’ black-and-white patterns, which others have shown seem to interfere with the flies’ vision, at least give them a bit of a break. Why equids are so susceptible to the flies’ attacks remains mysterious, but, as the researchers found, the zebras’ short coats may make them particularly vulnerable, and the diseases the flies carry are often fatal.See more ScienceShots.Sign up for our daily newsletterGet more great content like this delivered right to you!Country *AfghanistanAland IslandsAlbaniaAlgeriaAndorraAngolaAnguillaAntarcticaAntigua and BarbudaArgentinaArmeniaArubaAustraliaAustriaAzerbaijanBahamasBahrainBangladeshBarbadosBelarusBelgiumBelizeBeninBermudaBhutanBolivia, Plurinational State ofBonaire, Sint Eustatius and SabaBosnia and HerzegovinaBotswanaBouvet IslandBrazilBritish Indian Ocean TerritoryBrunei DarussalamBulgariaBurkina FasoBurundiCambodiaCameroonCanadaCape VerdeCayman IslandsCentral African RepublicChadChileChinaChristmas IslandCocos (Keeling) IslandsColombiaComorosCongoCongo, The Democratic Republic of theCook IslandsCosta RicaCote D’IvoireCroatiaCubaCuraçaoCyprusCzech RepublicDenmarkDjiboutiDominicaDominican RepublicEcuadorEgyptEl SalvadorEquatorial GuineaEritreaEstoniaEthiopiaFalkland Islands (Malvinas)Faroe IslandsFijiFinlandFranceFrench GuianaFrench PolynesiaFrench Southern TerritoriesGabonGambiaGeorgiaGermanyGhanaGibraltarGreeceGreenlandGrenadaGuadeloupeGuatemalaGuernseyGuineaGuinea-BissauGuyanaHaitiHeard Island and Mcdonald IslandsHoly See (Vatican City State)HondurasHong KongHungaryIcelandIndiaIndonesiaIran, Islamic Republic ofIraqIrelandIsle of ManIsraelItalyJamaicaJapanJerseyJordanKazakhstanKenyaKiribatiKorea, Democratic People’s Republic ofKorea, Republic ofKuwaitKyrgyzstanLao People’s Democratic RepublicLatviaLebanonLesothoLiberiaLibyan Arab JamahiriyaLiechtensteinLithuaniaLuxembourgMacaoMacedonia, The Former Yugoslav Republic ofMadagascarMalawiMalaysiaMaldivesMaliMaltaMartiniqueMauritaniaMauritiusMayotteMexicoMoldova, Republic ofMonacoMongoliaMontenegroMontserratMoroccoMozambiqueMyanmarNamibiaNauruNepalNetherlandsNew CaledoniaNew ZealandNicaraguaNigerNigeriaNiueNorfolk IslandNorwayOmanPakistanPalestinianPanamaPapua New GuineaParaguayPeruPhilippinesPitcairnPolandPortugalQatarReunionRomaniaRussian FederationRWANDASaint Barthélemy Saint Helena, Ascension and Tristan da CunhaSaint Kitts and NevisSaint LuciaSaint Martin (French part)Saint Pierre and MiquelonSaint Vincent and the GrenadinesSamoaSan MarinoSao Tome and PrincipeSaudi ArabiaSenegalSerbiaSeychellesSierra LeoneSingaporeSint Maarten (Dutch part)SlovakiaSloveniaSolomon IslandsSomaliaSouth AfricaSouth Georgia and the South Sandwich IslandsSouth SudanSpainSri LankaSudanSurinameSvalbard and Jan MayenSwazilandSwedenSwitzerlandSyrian Arab RepublicTaiwanTajikistanTanzania, United Republic ofThailandTimor-LesteTogoTokelauTongaTrinidad and TobagoTunisiaTurkeyTurkmenistanTurks and Caicos IslandsTuvaluUgandaUkraineUnited Arab EmiratesUnited KingdomUnited StatesUruguayUzbekistanVanuatuVenezuela, Bolivarian Republic ofVietnamVirgin Islands, BritishWallis and FutunaWestern SaharaYemenZambiaZimbabweI also wish to receive emails from AAAS/Science and Science advertisers, including information on products, services and special offers which may include but are not limited to news, careers information & upcoming events.Required fields are included by an asterisk(*)last_img read more

first_imgWith the NBA Finals currently underway in the United States, there’s never been a better time to delve into NBA 2K19. And what better way to delve into NBA 2K19 than with an Xbox One X at the lowest price ever.Yes, eBay is offering an Xbox One X 1TB console with a wireless controller and a digital download of the NBA 2K19 game for just $300. That’s a whopping $200 saving on the current list price on the official Xbox store in the United States.So far it only appears as if the deal – which is revealed at checkout – is available in the United States, where 809 units have been sold at the time of writing. There’s no indications of the stock levels available through the independent seller (who has 98.9% positive feedback from more than a quarter of a million reviews), so jump on it while you can.BUY NOW: Xbox One X 2K19 bundle for $300 (save $200)The deal is likely a tie in with the NBA Finals, although there’s no official reference to that on eBay’s website. Either way it’s an absolutely outstanding deal, ranking among the best we’ve ever seen for the top Xbox One console Microsoft offers.Our review called the Xbox One X “the pinnacle of console gaming”, offering native 4K HDR gaming, improved performance on some optimised games and surprisingly quiet running. It’s also the most powerful console money can buy, by the way.There’s an eight-core AMD processor running at 2.3GHz, and a much-improved AMD graphics chip with 40 Compute Units (versus 12 on the older models). There’s 12GB of high-speed memory for the console to use, with around 9GB set aside for games and graphics.Our reviewer added: “For me, the One X is a more compelling purchase than the One S – it’s the very latest in console hardware and the guarantee of smooth performance and some stonking visuals is mightily tempting.” This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Sign up for the Mobile NewsletterSign Up Please keep me up to date with special offers and news from Goodtoknow and other brands operated by TI Media Limited via email. You can unsubscribe at any time. We’d also like to send you special offers and news just by email from other carefully selected companies we think you might like. Your personal details will not be shared with those companies – we send the emails and you can unsubscribe at any time. Please tick here if you are happy to receive these messages.By submitting your information, you agree to the Terms & Conditions and Privacy & Cookies Policy. Show More Unlike other sites, we thoroughly review everything we recommend, using industry standard tests to evaluate products. We’ll always tell you what we find. We may get a commission if you buy via our price links.Tell us what you think – email the Editorlast_img read more