What is a notable feature of Scolytidae and Playpodidae adults?

Scolytidae, commonly known as bark beetles, and Platypodidae, known as ambrosia beetles, are primarily known for their behavior of tunneling into the bark of trees. This behavior is a significant characteristic that sets them apart from other wood-destroying insects. While they do tunnel into bark, it is also important to note that while they can affect the health of trees, their tunneling typically does not result in direct damage to structural wood used in construction.

The choice indicating that they tunnel into bark but do not damage structural wood accurately captures the essential behavior of these beetles. Their activities can lead to stress in trees, making them vulnerable to pathogens, but the structural integrity of wood intended for construction is not compromised directly by their presence.

The other options do not accurately represent the typical characteristics or behavior of these beetles. For example, while some species may display preferences when it comes to the type of wood they infest or light, it is not a defining feature across the families. Therefore, recognizing that these insects primarily affect the bark rather than structural components of wood is central to understanding their ecological role and impact.