Respuesta :
The reason is :a.They can gain more food for their offspring
Animals tend to protect their territory because they don't want  intruders to invade their territory.
Animals majorly protect their territory in order to protect their foods from been eating by intruders as this will enables their offerings to have enough foods to eat.
They as well guard  their territory in order to prevent intruders from invading the place they have prepare as their mating place.
Inconclusion  The reason why some animals defend  their territory after they have mated
and reproduced is :a.They can gain more food for their offspring
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