Simplify the following text for a Grade 8 native English-speaking person.
Original: Their most common social unit of jackals is that of a monogamous pair which defends its territory from other pairs by vigorously chasing intruding rivals and marking landmarks around the territory with their urine and feces .
Simplified: Jackals are monogamous ( each male live with only a female ) , and a pair defends its territory from other pairs . They mark the territory with urine and feces .