This skill is obtained by being awarded a Beetle Certificate when competing in the [Test of Khefre's Children]?.
Examining a Level 1 Beetle Certificate gives you a skill level of 2.
Examining a Level 2 Beetle Certificate increases your skill to 3.
Examining a Level 3 Beetle Certificate increases your skill to 4.
It is unknown if the skill has any use beyond allowing you to enter beetles in the higher leveled gardens (probably no longer checked when you try to buy Indonesian Bee Care and Silkworm Farming).