In the Pacific Ocean, a large species of marine worm called the giant tube worm lives up to a mile underground. The worms can be found inside long, white protective tubes. Each worm has a red plume that emerges from the end of its tube to exchange compounds with the surrounding environment. Bacteria in a specialized organ of the giant tube worm help the worm to convert the inorganic compounds to organic compounds.
Terrestrial systems, such as clay hills, also support communities of large worms. The stream banks and nearby hills of Victoria, Australia, are home to an earthworm called the giant Gippsland earthworm. These species usually do not leave their deep, moist burrows. The giant Gippsland earthworm obtains food by finding and taking in nutrients from the soil as it tunnels through the ground.
Both the giant tube worm and the giant Gippsland earthworm have adapted to changing conditions in their environment. Each species has developed the behavior of
a
building hidden homes that protect them from predators.
b
reproducing asexually using generalized organs.
c
becoming dependent on internal bacteria to generate food.
d
using salt from their surrounding environment to purify water.