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first_imgFilthy, smelly, repulsive. There are a lot of ways to describe cockroaches, but “full of personality” usually isn’t one of them. Yet a team of scientists has not only found evidence that the scuttling insects have personalities, but also discovered that when cockroaches get together, they create a group personality. The group personalities of cockroaches vary, too.“A lot of studies show personality in other invertebrates,” says Isaac Planas-Sitjà, a behavioral ecologist at the Free University of Brussels and the lead author of the study. “But no one had looked at the American cockroach.”Over the last 2 decades, scientists have documented personalities—that is, consistent behaviors, such as boldness, shyness, sociability, or aggressiveness—in a range of invertebrate species, from octopuses to water striders to social spiders. Planas-Sitjà was drawn to cockroaches not out of fondness, but because they don’t live in societies with leaders and followers—social castes that can make it difficult to spot an individual’s personality. “They are all independent, even though they are gregarious,” he says.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(*)To find out if the cockroaches had personalities, Planas-Sitjà and his colleagues glued tiny radio frequency identification chips to the thoraxes of 304 roaches so that they could track each insect after it was placed in a new environment. The scientists divided the animals into 19 groups of 16 individuals (all males about 4 months of age, because an animal’s age and gender can affect its behavior, making it more difficult to tease out its personality type). Three times a week, the team placed each group in the middle of a brightly lit, plastic circular arena that was surrounded by an electric fence so that the roaches could not escape. Two identical Plexiglas disks covered with red filters hovered just above the arena, creating red circles that the light-phobic insects perceived as shelters. Each shelter was large enough for all 16 cockroaches to gather beneath.Over a 3-hour period, the scientists measured the amount of time individual cockroaches spent inside a shelter and how much time each took to pay its first visit. To see if the insects reached a consensus about where to gather (an indicator of group personality), they tallied how many insects were beneath each disk at the end of the experiment. Their analysis showed that like other species, from spiders to lions, these cockroaches had shy and bold individuals. The shy roaches ran for cover as soon as they entered the arena, whereas bold individuals spent more time exploring, the team reports online today in the Proceedings of the Royal Society B. And the roaches consistently behaved in these same ways in each test.Despite these individual personality differences, by the end of each experiment the groups always ended up crowded together beneath the same shelter. “There is a collective dynamic—a social influence—that dilutes the individual personality differences,” Planas-Sitjà says. “So in the group, you end up with a similar behavior in everyone.” This conformity happens even though the researchers know, based on previous experiments, that some cockroaches when left alone in the arena never dash to a shelter, whereas others spend only a short amount of time beneath one. Yet they change their behaviors as soon as they’re in a group. “Then they all run to the shelter,” says Planas-Sitjà, who hopes to tease out why and how this happens with further experiments.The team’s discovery that “the collective outcome [the group personality] is different from the sum of the personalities is very cool,” says Noa Pinter-Wollman, an animal behaviorist at the University of California, San Diego, who was not involved in the study. “It implies that the whole is greater than the sum of its parts.” Social spiders, bees, and ants are also known to have group or colony personalities.“To be able to show group personality as they have done is very exciting and intriguing,” adds Odile Petit, an ethologist at the French national research agency CNRS in Strasbourg. “And they’ve shown that individuals and their personalities matter even in simple animals.” Yes, even in cockroaches.last_img read more

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first_img This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. 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 Editor Consumer electronics don’t tend to have the best environmental credentials. No matter what feel-good terms like “recycling” phones imply, the truth is that e-waste is a huge problem that’s only getting worse. Korvaa, the pair of headphones pictured above, may offer part of the solution. Rather than being made from the usual environmentally troubling mix of plastic, leather and mesh, they’re made from yeast, mushrooms and microbe-grown materials.Related: Best headphonesA joint effort from Finnish design studio Aivan, VTT Technical Research Centre of Finland and Aalto University, Korvaa is just a prototype for now, and crucially doesn’t actually function as much more than a set of green earmuffs – there are no electronics contained within. But it is potentially a sign of how things could go if we humans take drastic steps to get to grips with our e-waste addiction.“Synthetic organisms can produce a variety of desired chemicals, materials, medicine or fuels from renewable raw materials, waste fractions and CO₂,” Aivan explains. “This technology will have a paramount role in the transition from a fossil-based economy to a sustainable, circular bioeconomy.”And the name? It’s a Finnish pun. “Korva” means “ear”, while “Korvaa” is a verb meaning “to substitute, compensate or replace.” Pretty smart for a headphone design based on substitutions.Related: Best wireless headphonesThe headband is 3D-printed bioplastic, made from yeast-produced lactic acid. The ear padding is Hydrophobin – a foamy protein produced by fungus and plant cellulose. The faux leather comes from another fungus, while the mesh over the speakers (or rather, where the speakers would go) is biosynthetic spider silk that comes courtesy of microbes. The outer foam – and looking closely, the least convincing part of the design at the moment – is a mycelium-cellulose composite.Here are all the pieces broken down:Would you be happy with a fungus-based headset? Let us know what you think of the design on Twitter: @TrustedReviews. 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.last_img read more