Elephant seals were named for their large proboscis (nose). In mature males, or bulls, this proboscis starts above the nostrils and hangs down in front of the mouth. This prominent characteristic is thought to be used to create the dominance hierarchies between competing males. However, some researchers believe it may also assist in creating their deep, booming vocalizations, which are a critical component in their society. Male life spans may reach up to 17 years, while females may live up to 22 years. Although female elephant seals only grow to be between 6-10ft (2-3m) long and about 882-1323lbs (400-600kg), mature males can get to be as long as 13-16ft (4-5m) and weigh up to 5071lbs (2300kg)!