 Following accusations of sexism, the second series used two islands, with 14 men on one, and 14 women on the other.The third series continued the gender divide theme and featured eight men and eight women abandoned on opposite sides of a single island.The fourth series, which aired from April 2017, focused primarily on age rather than gender, featuring initially separate tribes of older people (30 to 66 years) vs younger people (18 to 30 years).