The Goebies are a race of amphibious looking creatures with large rocks on their backs found on the planet of Mazcab (also known as Chantli.)
They do not die of old age, but instead are killed once the rock growing on their body becomes too heavy for them to carry (much like giant lobsters in the real world). The rocks on their backs contain their lungs, so attempts to chip away at the rock to keep them alive longer will instead kill them. However, this can be circumvented by having their body hung on a rack, so that the rocks on their backs are unable to crush them, as seen by the ancient goebie during the Call of the Ancestors quest.
Goebies are often subjugated by the Airut to harsh penalties, such as their villages being constantly raided. The goebies fight back with nemi poison, which weakens an Airut when injected onto them.
Although Jagex have stated they are a genderless species, many Goebies are identified with male and female pronouns in-game. Additionally, a Goebie mother and father may be encountered.
^Xinachto, "Call of The Ancestors", RuneScape. "Mazcab... This is a new sound...used by the rock-bearers. Before it...there was Chantli. A different sound...with the same meaning. They refer to the plants... To the trees... To the creatures. Mazcab is I... Chantli is I... I am life."