Physical Characteristics
The adult male is much bigger than the adult female. This difference in size is called sexual dimorphism.
Head Shape
Male Female Pup
As the male elephant seal matures, his head grows and broadens while the female's head is narrower and more pointed.
Eyes
The black eyes are large and round to aid in light-gathering in the depths. When on land, the elephant seal's pupil will contract to a small slit, and oily secretions will constantly wash over their eyes. Because they have no tear-ducts, this moistening liquid will run down the sides of their faces leaving visible damp trails. An additional characteristic of elephant seal eyes is that each eye can be opened and closed independently of the other.
Ears
The flapless ears appear like a pinhole not far behind each eye. Although very small, their ears still allow them to hear well on land and enable them to pinpoint the location of the source of any sound.
Nose
The nose on the adult male can grow up to two feet in length and is called a proboscis or trunk. The nostrils or nares of all elephant seals can be opened and closed independently of one another.
Whiskers
The whiskers on an elephant seal are called vibrissae. Apart from being used in the water to sense prey, these whiskers are also used on land during interaction between the seals. If a seal holds its whiskers forward, this is seen as an aggressive move by others. In addition, in a fight between males or between a female and a male, the seals may try to bite at the whiskers of the opponent to bring about a retreat.
Teeth
Elephant seals have thirty teeth, the biggest and sharpest of which are the four canines. Since their molars are not made for chewing, they tend to swallow their soft-bodied prey whole. ( By the time the pups are just over a month old, they are equipped with all thirty teeth so they can start eating solid food once they've learned how to catch it ! )
Tongue
Elephant seals are born with a cleft or divided tongue. Scientists are unsure as to the purpose of this split at the front of the tongue, but it may make it easier for the pup to grab and hold onto the mom's teat while nursing. Interestingly enough though, this specialized tongue shape does not change throughout their lives.
Cornified Chest
The pinkish cornified chest or chest shield of the older male elephant seals is calloused skin which forms as a result of years of fighting for dominance.
Fore Flippers
Each fore flipper has five webbed fingers with each digit having a fairly long claw-like nail. These nails are primarily used for scratching various parts of their itchy bodies. At other times, the fore flippers can be used to hoist the heavy front part of their bodies into an upright position, climb over rocks, steer them while swimming, help keep their balance during their vertical floats ( males ), or even to clasp, scratch, or bat away an annoying intruder.
Back Flippers
Elephant seals have a pair of webbed hind flippers that are primarily used for swimming. Each hind/tail flipper has five digits with webbing in between. A vestigal nail is located beneath a small opening above the end of each digit, but has no known use. On land, the back flippers help balance the elephant seal when he/she is in an upright position and/or is propelling him-/herself forward.
Tail
Elephant seals do have a small straight tail that is visible between the hind flippers.
Fur
The fur changes color gradually over a period of time. Different ages have different colors. The pups have a black or very dark brown coat of fur with fairly long strands of hair while the weaners have a silver-gray coat of fur. Yearlings and 2-3 year-olds have a coat of fur that is anywhere from dark gray to tan. The adult males are usually a darkish brown while the adult females are gray to tan in color, with both sexes being darker on the top than on their bellies. The fur is not their insulator, but it surely helps protect the blubber layer from cuts and superficial wounds. The fine hair of the fur may also help lessen water drag in swimming and diving.
Blubber
Elephant seal blubber is a several inches thick layer of fat that has numerous vessels both for blood and lymphatic fluid transportation. This lipid-rich, collagen fiber-laced blubber makes up the hypodermis and covers the whole torso. It is strongly attached to the muscles and skeleton of the elephant seal by a highly organized fan-shaped network of tendons and ligaments. In adult males, this layer of blubber can account for up to 50% of their body weight. The blubber is also the source of their highly efficient thermoregulation system which constantly moderates their body temperature.
During their fasting times on land, the blubber layer is the elephant seal's source of ' food '. This specialized metabolism causes water to be produced as a by-product as they draw upon their stored energy to survive. Despite having this handy built-in food-storage area, however, both adult males and adult females lose about 1/3 of their body weight during the birthing/mating season in January and February of each year.