Wednesday, April 4, 2012

Fun Facts


The seeds of some acacia tree species cannot germinate unless they have passed through a giraffe's digestive system.

Reproductive System

Female giraffes are able to concieve when they turn 5 years old. They have a gestation period of 15 months!
Newborn giraffes are called calves and they usually stand 6 feet and weigh approx. 150 lbs. During the birthing process they are dropped about 6 feet to the ground from their mother.Then they stand on wobbly legs about 20 minutes after birth and begin to nurse within 1 hour. Male calves are weaned at about 15 months, female calves a couple of months later

Digestive System



       

Diet

Giraffes are herbivores meaning  eat a variety of leaves, shoots, vines, flowers, and herbs from plants. Their favorite food appears to be the leaves of the acacia tree. Giraffes get most of their water from their food, but occasionally will bend to drink from a pool of water

Length

Giraffes spend up to 16 or even 20 hours eating and can consume up to 145 pounds of food a day.

Tongues

Giraffes have long, muscular tongues that are dark colored to prevent sunburn. They have thick saliva and tough lips help them eat thorns, such as those of their favorite, the acacia, without getting cut!

Digestion

Giraffes are ruminants, which means they regurgitate their food after partial digestion and chew it further.They also have four compartments in their stomachs.

Circulatory System


   

Giraffes have one of the most powerful hearts of all mammals weighing approximately 24 pounds and measuring 2 feet long!

Giraffes have long necks which means that their heart must work very hard to pump the blood up the neck to the brain. This makes their blood pressure double the amount of most mammals! In the upper portion of their necks there is a complex pressure regulatation system that maintains blood flow when the giraffe bends down to drink. In their brain there are elastic blood vessels that connect to one way valves in the neck to prevent the head from swellin when they bend over. If these things did not exist a giraffe would not be able to survive.

In their legs the vessels are under great pressure, so much that any other animal would not be able to handle it. Fortunately, giraffes have a layer of tight skin on their legs to maintain pressure and keep the vessels from bursting. Their thick skin and inner fascia also prevents blood pooling and excessive bleeding if the giraffe were to ever get cut. NASA scientists are studying this adaptation of the giraffe and looking into creating a similar material for gravity-suits.
                     

Tuesday, April 3, 2012

Respiratory System


Imagine your lungs 8x the size they are now..that's how large a giraffe's lungs are!!!

Why is this? Well the giraffe needs to bring oxygen to much larger muscles than us! The air travels down the trachea into the lungs and is then delivered to the rest of their body. The trachea is very large and narrow which leaves an area of "dead space" where "old air" remains in the giraffe. To help with this giraffes breathe at 1/3 of the rate that we do. They still breathe in oxygen and expell carbon dioxide just like humans.

                                    

Nervous System

Mammals have a left reccurent laryngeal nerve that is longer than the right. Giraffes have an even longer one than all other mammals that can reach up to 6ft 7inches. this begins in the brain and branches out down their neck. These cells reach up to 5 meters in large giraffes!

Skeletal/Muscular System

 



Humans and giraffes have the same amount of bones in their neck! Their vertebrae are just much larger than ours.

Giraffes are the tallest standMing creature known today with a height maxing at approximately 19ft. The majority of their length is actuall in their neck which can weigh up to 600lbs alone!
As you can see in the picture they have a skull. This equipped with teeth adapted for consumption of leaves. Giraffes also have horns placed on top of their skull. Following the diagram you can see that the have large vertebrae in their neck, shoulder and hip joints, ribs, fore legs, hind legs, feet, heel bones, and wristbones. Unlike humans, a giraffes heel is not directly on their feet, it is higher up the leg. The front pair of legs are slightly longer than their hindlegs.

Muscular System

The reason the giraffe's forelegs are longer than their hindlegs is because of the heavy muscular development on the base of their neck, or their shoulders. Most of their muscle is found in their neck, which is fairly flexible to aid in fethcing water down low or plants up high. Another muscular adaptation is that their tongues were formed to extend up to 18 inches.