AUSTIN (KXAN) — It might sound unbelievable, but viewers are sending in videos of fire ants floating on floodwaters, forming living rafts out of their own bodies. On Wednesday morning, a man shared video of one such raft drifting on Lake Travis.
When their underground nests flood, fire ants link their legs and jaws together to create buoyant, self-assembled mounds. These floating colonies can contain thousands of ants — and they can still bite or sting if disturbed.
These fire ant colonies can contain thousands of worker ants, and can still bite or sting those who interfere with the floating colony.
Fire ants are widespread in Texas, and researchers at Texas A&M University are studying how they respond to flooding. The insects bite one another and interlock their limbs, forming tightly packed rafts that don’t sink. Their waxy skin helps repel water and keep the group afloat.
“It’s called a self-organizing or self-assembling process. And it’s something only social insects do,” LeBrun said. A research scientist at the University of Texas’ Brackenridge Field Lab in central Austin, LeBrun has researched ants for three decades.
“There are a lot of other structures that ants make in a similar way. For example, army ants will make bridges across rivers,” LeBrun said, but still, this raft is rare. Fire ants he believes are the only ants that do this.
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