Called "primitives" by humans, at least three different types of "Uxarieans" were seen on the planet. The Third Doctor hypothesised that perhaps they were all mutations of the same root species. Before he could conduct any tests to determine this, Jo prodded him to "stop philosophising" and return his attention to the more pressing matters at hand. There were no animals on the planet, just some bird and insect lifeforms. (TV: Colony in Space