Like guards on duty, soldier termites stand watch at the center of their mound to protect the nest. Long passageways extend outwards from this central nest to foraging sites where worker termites collect food for the colony. If an aardvark or other predator creates a hole in the mound, these commandoes repeatedly ram their heads into the ground to create drumming alarms that alert worker termites in the corridors to quickly retreat to the nest. This vibrational communication has been observed in several species of termites, but scientists wanted to see how these alarm signals were communicated across mounds with a diameter up to 30 meters in length. So researchers opened up the mounds of Macrotermes natalensis termites in a South African mountain range and filmed the soldiers’ drumming signals using a high-speed video camera. They also implanted devices in the ground at various locations to measure the vibrational speed of the head-banging. M. natalensis termites pound their heads into the ground at a speed of about 0.6 m/s, researchers report online today in The Journal of Experimental Biology. But when the team recreated the vibrations produced by a single termite using a computer and device that produces low-frequency pulses through the mound passageways, they found that after just 40 cm, the signals were no longer strong enough to be picked up by other termites. Because worker termites can register drumming alarms meters away, the researchers suggest that the soldiers use social reamplification to extend the life of the signal. Like how the wave spreads through a crowd, soldier termites respond to the drumming of nearby nestmates by drumming themselves until every worker is alerted of the attack.
The Alaska House of Representatives has passed an operating budget, signaling the end of a stalemate over the state’s multi-billion-dollar budget deficit.The $5 billion budget includes changes agreed to by a conference committee on Wednesday. It funds a contractual cost-of-living increase for public employees, but offsets that directing the governor to make a $30 million reduction to agency operations. The compromise also restored some cuts that had been made to education and the ferry system.The vote on the bill was 32 to 7, with half of the Democratic Minority voting against it, because it did not reduce the payment of oil tax credits or advance some of their other priorities like Medicaid expansion. Rep. Lora Reinbold, a conservative Eagle River Republican who was kicked out of the majority caucus earlier this year, also voted against it, but because she thought it spent too much.However, Democrats were unanimous in their support for paying for the operating budget by making a withdrawal from the Constitutional Budget Reserve. The vote was 38 to 1, well above the three-quarter threshold to access the rainy day fund. Reinbold was the lone no vote.The Senate is scheduled to take up the budget bill, along with a sexual abuse prevention bill known as Erin’s Law later today. If the two bodies successfully end their special session on Thursday, state government will no longer be at risk of shutting down on July 1.