{"302951":{"#nid":"302951","#data":{"type":"news","title":"Going Inside an Ant Raft","body":[{"value":"\u003Cp\u003EThree years ago, Georgia Institute of Technology researchers took a close look at \u003Ca href=\u0022http:\/\/www.news.gatech.edu\/2011\/04\/26\/how-fire-ants-build-waterproof-rafts\u0022\u003Ehow fire ants work together to build waterproof rafts\u003C\/a\u003E to stay alive. By looking at the edges and tops of rafts, the team discovered that ants grip each other with their mandibles and legs at a force of 400 times their body weight.\u003C\/p\u003E\u003Cp\u003ENow, the researchers have taken an even closer peek. They froze ant rafts and scanned them with a miniature CT scan machine to look at the strongest part of the structure \u2013 the inside \u2013 to discover how opaque ants connect, arrange and orient themselves with each other.\u003C\/p\u003E\u003Cp\u003E\u201cNow we can see how every brick is connected,\u201d said Georgia Tech Assistant Professor David Hu. \u201cIt\u2019s kind of like looking inside a warehouse and seeing the scaffolding and I-beams.\u201d\u003C\/p\u003E\u003Cp\u003EHe found a lot of beams.\u003C\/p\u003E\u003Cp\u003EOn average, each ant in a raft connects to 4.8 neighbors. Ants have six legs, but using their claws, adhesive pads and mandibles, each critter averages nearly 14 connections. Large ants can have up to 21. Out of the 440 ants scanned, 99 percent of them had all of their legs attached to their neighbors. The connectivity produces enough strength to keep rafts intact despite the pull of rough currents.\u003C\/p\u003E\u003Cp\u003EHu and his team also noticed that the insects use their legs to extend the distances between their neighbors.\u003C\/p\u003E\u003Cp\u003E\u201cIncreasing the distance keeps the raft porous and buoyant, allowing the structure to stay afloat and bounce back to the surface when strong river currents submerge it,\u201d said Nathan Mlot, a Georgia Tech graduate student in the George W. Woodruff School of Mechanical Engineering who worked on both studies.\u003C\/p\u003E\u003Cp\u003EMlot and the rest of the research team also found that smaller ants tend to fill in the spaces around large ants. This keeps water from seeping in and prevents weak spots in the raft. The insects, large and small, arrange perpendicularly rather than parallel. This adds to the adaptability of the raft, allowing it to expand and contract based on the conditions. The same is true when ants build towers and bridges for safety and survivability.\u003C\/p\u003E\u003Cp\u003EOne thing the CT scan can\u2019t solve, however: how the ants know where to go and what to do. Their cooperation is a mystery the research team hasn\u2019t figured out \u2013 yet. \u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u201cFire ants are special engineers,\u201d said Hu, a faculty member in the Schools of Mechanical Engineering and Biology. \u201cThey are the bricklayers and the bricks. Somehow they build and repair their structures without a leader or knowing what is happening. They just react and interact.\u201d\u003C\/p\u003E\u003Cp\u003EBetter understanding of this phenomenon could lead to new applications for people and machines. For instance, Hu envisions robots than can link together to build larger robots or bridges made of materials that can self-repair.\u003C\/p\u003E\u003Cp\u003E\u201cIf ants can do it, maybe humans can create things that can too.\u201d\u003C\/p\u003E\u003Cp\u003EThis study appears in the June 11 edition of \u003Ca href=\u0022http:\/\/jeb.biologists.org\/content\/217\/12\/2089.abstract\u0022\u003EThe Journal of Experimental Biology\u003C\/a\u003E.\u003C\/p\u003E\u003Cp class=\u0022Author\u0022\u003EReference: Foster, P. C., Mlot, N. J., Lin, A. and Hu, D. L. (2014). Fire ants actively control spacing and orientation within self-assemblages. \u003Cem\u003EJ. Exp. Biol.\u003C\/em\u003E 217, 2089-2100.\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EThis research was partially supported by the National Science Foundation (NSF) under grant PHY-1255127. Any conclusions expressed are those of the principal investigator and may not necessarily represent the official views of the NSF.\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EThis material is based upon work supported by the Army Research Office under Award Number \u003C\/em\u003EW911NF-12-R-0011\u003Cem\u003E. Any opinions, findings and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the Army Research Office.\u003C\/em\u003E\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Researchers look to CT scan to visualize connectivity phenomenon"}],"field_summary":[{"value":"\u003Cp\u003EResearcher froze ant rafts and scanned them with a miniature CT scan machine to look at the strongest part of the structure \u2013 the inside \u2013 to discover how opaque ants connect, arrange and orient themselves with each other.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"On average, each ant in a raft connects to 4.8 neighbors and has 14 connections."}],"uid":"27560","created_gmt":"2014-06-12 09:19:48","changed_gmt":"2016-10-08 03:16:33","author":"Jason Maderer","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2014-06-12T00:00:00-04:00","iso_date":"2014-06-12T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"302911":{"id":"302911","type":"image","title":"Ant raft","body":null,"created":"1449244592","gmt_created":"2015-12-04 15:56:32","changed":"1475895007","gmt_changed":"2016-10-08 02:50:07","alt":"Ant raft","file":{"fid":"199599","name":"ant_raft.jpg","image_path":"\/sites\/default\/files\/images\/ant_raft.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/ant_raft.jpg","mime":"image\/jpeg","size":995240,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/ant_raft.jpg?itok=pTt3Pbkd"}},"302891":{"id":"302891","type":"image","title":"Microscopic view of ants","body":null,"created":"1449244592","gmt_created":"2015-12-04 15:56:32","changed":"1475895007","gmt_changed":"2016-10-08 02:50:07","alt":"Microscopic view of ants","file":{"fid":"199597","name":"ants.png","image_path":"\/sites\/default\/files\/images\/ants_0.png","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/ants_0.png","mime":"image\/png","size":1702811,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/ants_0.png?itok=Wy5_TnIp"}},"302901":{"id":"302901","type":"image","title":"Ant assemblages","body":null,"created":"1449244592","gmt_created":"2015-12-04 15:56:32","changed":"1475895007","gmt_changed":"2016-10-08 02:50:07","alt":"Ant assemblages","file":{"fid":"199598","name":"assemblages.png","image_path":"\/sites\/default\/files\/images\/assemblages_0.png","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/assemblages_0.png","mime":"image\/png","size":2882302,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/assemblages_0.png?itok=oqIkE5qT"}}},"media_ids":["302911","302891","302901"],"related_links":[{"url":"http:\/\/jeb.biologists.org\/content\/217\/12\/2089.abstract","title":"Journal Article"},{"url":"http:\/\/hoogle.gatech.edu\/","title":"David Hu Research Website"},{"url":"http:\/\/coe.gatech.edu\/schools\/me","title":"George W. Woodruff School of Mechanical Engineering"},{"url":"http:\/\/www.biology.gatech.edu\/","title":"School of Biology"}],"groups":[{"id":"1214","name":"News Room"}],"categories":[],"keywords":[{"id":"66521","name":"ant"},{"id":"20471","name":"Ants"},{"id":"95361","name":"CT Scan"},{"id":"297","name":"David Hu"},{"id":"14335","name":"Fire Ants"},{"id":"95351","name":"Raft"}],"core_research_areas":[{"id":"39471","name":"Materials"},{"id":"39521","name":"Robotics"}],"news_room_topics":[{"id":"71881","name":"Science and Technology"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EJason Maderer\u003Cbr \/\u003EMedia Relations\u003Cbr \/\u003E\u003Ca href=\u0022mailto:maderer@gatech.edu\u0022\u003Emaderer@gatech.edu\u003C\/a\u003E\u003Cbr \/\u003E404-385-2966\u003C\/p\u003E","format":"limited_html"}],"email":["maderer@gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}