Complex sentence: These dewlaps are usually of a different color from the rest of their body and when enlarged they make the lizard seem much bigger than it really is, used primarily when indicating territorial boundaries and for males to attract females during the mating season.
Split into simpler sentences: These dewlaps are usually of a different color from the rest of their body and, when enlarged, make the lizard seem much bigger than it really is. The dewlap is primarily used when indicating territorial boundaries and for males to attract females during the mating season.