Complex sentence: The jack jumper ant's sting generally only causes a mild local reaction; however, along with other ants in the "Myrmecia" genus, it is one of the very few ant species that can be dangerous to humans.
Split into simpler sentences: The jack jumper's sting generally only causes a mild local reaction. However, along with other ants in the "Myrmecia" genus, it is one of the very few ant species that can be dangerous to humans.