Beetles are wood-boring insects (they live & grow in wood). They can damage both softwood and hardwood. The larvae of the beetle (offspring) dig through the wood digesting the cellulose of the wood. After about three (3) years they form a pupal chamber near the surface and there they will become adult beetles.
In the summer time beetles bite and claw their way out of the wood they were foraged in to the surface. Here they form the common round flight-holes that are 1.5 mm in diameter typically seen near beetle homes. Once they have finished mating, females lay their eggs in any cracks, crevices or old flight-holes that may have previously been created. Their eggs will hatch and a new generation of beetles begin a fresh life cycle of feeding and foraging.