Anomalies is the term used by the X-Series to describe other Transgenics that do not look human.
The term was first used by a younger Ben when he used to tell the other X5's stories.
Genetic Enhancements
The anomalies were created with extra DNA from a kind of animal or the like so they would better be able to with stand harsh environments or certain jobs, such as building trenches.
Joshua has also been shown to be stronger than the X5 series.