Carpenter ants will battle it out at the grand opening of the Gateway Science Museum this month, featuring animatronic displays built by Garner Holt Productions in San Bernardino. With bodies 5 feet long, one animatronic ant will partially pop in and out of a hole in a giant piece of decaying “wood” as the other flails its leg in a contest. In another area, a statuesque green praying mantis, 9 feet tall, shows off its six legs — four for walking and two for grasping its prey. The sharp prongs on its upper appendages might clear up some questions about how a praying mantis can cling to a car that is speeding down a highway. Other giant insects that are part of the “Backyard Monsters” display will include a scorpion bigger than a couch and a huge dragonfly. Scott Burson of Garner Holt said the display was recently featured at the San Diego Museum of Natural History and the Bishop Museum in Honolulu. His company also recently finished a job fine-tuning the animatronic displays at Disneyland, including the “It’s a Small World” ride.