He works for the Forestry Bureau but after work he gets home and takes care of the worm. Zhiwei keeps the worm in his backyard.
Although the average length of an earthworm is up to 70 mm, earthworms can reach up to 3 meters in length. Earthworm sizes vary by species or by the environmental factors. For example an earthworm that lives in a humid place almost all its life will tend to grow longer than a worm that lives mostly in a dry place.
Biologists will study the earthworm in more detail in order to classify it and identify why it grew so much.