Many birds nest and sleep in hedges and eat insect pests.
The reason for snakes symbolizing worth was because they ate rats and other pests.
Sparrows can be beneficial to humans as well, especially by eating insect pests.
Bats are important in eating insect pests, reducing the need for pesticides.
This could happen should genetically altered plants become weeds, or should insects designed to eat certain pests develop a taste for others.
Though a few species of ground beetles do eat plants, a vast majority eat soft-bodied pests like cutworms and slugs.
The value of bats that eat pests on cotton crops in Texas has been valued at $741,000 (£452,000) annually by researchers.
It is also attractive to hoverflies (family Syrphidae), which are useful as biological pest control agents because they eat aphids and other pests.
A single bat can eat 500 to 1,000 mosquitoes per night as well as other insect pests.
Some species of ants are used for pest control (they eat pests that destroy food for humans).