Poaching is also a dire problem for the species and many also fall prey to lions and crocodiles, their only real predators besides humans.  There are nine remaining sub-species of giraffe living in scattered geographic regions of the continent, each with its own coloring and pattern.  They are the Nigerian, Nubian, Baringo (or Rothschild’s), Masai, Reticulated, Thornicroft’s, Kordofan, Angolan and the Southern Giraffe.  All species have a life expectancy of around 25 years in the wild and 35 years in captivity.  The distinctive rusty, orangish, or blackish coats are broken into patches with whitish outlines which are used for camouflage.  All-whitish giraffes exist but are an extremely rare find.   Giraffes are only found naturally on the continent of Africa and their ranges keep diminishing due to human encroachment, population growth and habitat degradation. 

The males many times will spar by swinging their heads viciously at one another.  This behavior to establish dominance is called “necking” and it can become quite violent with powerful blows, but is rarely ever fatal.  As male giraffes age, calcium deposits form on their skulls and other horn-like bumps begin to develop.  They can have up to three of these large bumps, one in the forehead region and two in the rear of the skull, making it appear like they have five horns.  Males are called bulls and females are called cows.  The females travel in loosely structured herds and the older males are usually solitary, spending most of their time in search of female herds that contain prospective mates.  Both bulls and cows are born with horns on their heads, called ossicones.  The horns are formed from ossified cartilage that has transformed into bone and are covered by skin and tufts of hair.  The ossicones help to distinguish between males and females, as males usually have much larger bare ones that have been worn away over time during combat with other giraffes.   

The young calves receive a rather rude awakening at birth, falling more than five feet to the ground.  Infants can stand up and nurse within around half an hour and within ten hours after birth they are running with their mother.  They grow about an inch each day and double their height within about 11-12 months.  Within that first year, about half of the young giraffes fall prey to hyenas, the great cats, wild dogs, and other predators. Female giraffes form a type of daycare for the the group to watch out for the young.  One of the females in the herd will stay behind and babysit all of the youngsters while the others go out foraging for food.  She protects and defends them using her soup bowl-sized hooves as weapons.  The defensive kick of an adult giraffe is enough to seriously injure even the most determined predator and is strong enough to kill a lion.  

Giraffes have the highest blood pressure of any animal in the world, with the heart pumping around 16 gallons of blood each minute.  If they run too long or hard they will suffer a heart attack due to the elevated blood pressure. The jugular vein contains a series of one-way valves that prevent the back flow of blood when the giraffe’s head is down to drink water, preventing blackouts.   Despite its extreme length, the giraffe’s neck is actually not long enough to reach the ground.  This makes it difficult and dangerous for giraffes to drink at a water hole.  In order to do so, they must awkwardly spread their front legs or kneel to the ground making them vulnerable to attack.  Despite their size they are always on the look-out for predators and only sleep for around half and hour at a time.  Members of the herd tend to drink or sleep in shifts, so one animal can keep a look out for lions, leopard or hyena, which could attack a calf.  Throughout the night, a giraffe may deeply sleep for five to 10 minutes lying down, yet they rarely sleep more than 20 minutes total per day.  Although rarely heard, giraffes can moo, roar, hiss and whistle to communicate with one another.