Giraffe can browse the crowns of small trees; big bulls can reach higher than cows. Giraffe feed mainly on broad leaved deciduous foliage in the rains and on evergreen species in other seasons. A reinforced skull usually absorbs the impact of these blows, but occasionally an animal is knocked unconscious and very rarely even dies during such a fight.
In the upper neck, a complex pressure-regulation system called the rete mirabile prevents excess blood flow to the brain, when the giraffe lowers its head to drink. Conversely, the blood vessels in the lower legs are under great pressure because of the weight of fluid pressing down on them. In other animals, such pressure would force the blood out through the capillary walls. Surprisingly, even with its long neck, the giraffe has the same number of vertebrae in its neck as humans and other mammals.
Giraffe have seven cervical vertebrae, but each one can be about 25 cm long. Proudly wear your support for GCF! Proceeds from every sale help fund our conservation work in Africa. We promise not to clutter your inbox. To confuse matters further, a study undertaken in had concluded that giraffes do indeed use their necks to graze the topmost branches.
The researchers fenced off some trees with wire netting so that smaller herbivores could not reach the lower branches, but giraffes could still graze by reaching over the top of the netting.
When the fenced-off trees were compared with unfenced trees, the researchers found that the giraffes did, in fact, browse the higher branches when other species were competing for the lower leaves. So perhaps Darwin was right after all: giraffes use their long necks in order to avoid competition. Fossil evidence supplies further backing for his hypothesis: it appears that giraffes developed their long necks between fourteen and twelve million years ago, a period during which Africa underwent a general aridification and its forests gave way to savannah.
As the number of trees diminished, competition for each tree must have increased, so favouring the selection of a long neck. Fortunately, one explanation does not exclude the other: the ability to graze the higher branches is probably an advantage that shaped the evolution of the long neck for both sexes, while its use as a cudgel in competition between males is an evolutionary factor that explains the significant difference in thickness between male and female skulls.
Perhaps the lofty view it affords helps the animals spot predators, or maybe its large surface area assists in regulating body temperature. Mar 12, Reegan Buck Jan 9, I loved this article because I really loved giraffes.
I ask this question all the time and the question was answered in the article. Jan 9, May 4, Trista Jan 9, Jan 10, Aren't they amazing, Trista? Have you ever seen one up close at the zoo before? Joyce Dec 6, Hey,I just wanted to say giraffes are my best friends I would live with them If I could I also love wonderopolis. I love grafes so much i even had a brthday for them!!!!!!!!!!!!
Dec 7, Joyce Dec 7, Dec 8, We're really glad to be your Wonder Friend, Joyce! Lucy Mar 21, Mar 22, Annabelle Mar 16, Mar 17, Thanks for sharing your thoughts about this Wonder, Annabelle!
We value your opinion! Tharp Mar 15, My class really enjoyed this wonder and we learned lots of things! Elaine Mar 14, Mar 16, We're glad you liked this Wonder, Elaine! AF Mar 13, Isn't the solution to Giraffes' long necks is the theory of evolution established by Darwin? But it is still a very helpful resource to learn! Nice job Wonderopolis! Mar 15, Giraffes look so amazing! Why they are not common although they don't have many predators?
EJ Mar 13, They have long necks in order to reach food on the trees! Alazay Dorado Mar 13, Giraffes need their long necks to survive dont they? Hi, Alazay! We hope this Wonder was helpful! Maurice Jun 6, Yes, I understand why giraffes have evolved with long necks- they help them to survive. But why have not more animals done the same? Or have they faced competition from giraffes, and become extinct?
Hi, julian! Thanks for stopping by! Jun 8, Feb 14, I need a question from this article. Feb 16, Hi, Wonder Friend! Sofia Dec 12, I love Giraffes and when I went to the zoo I was amazed at how tall they were.
Wonderopolis Dec 12, It is amazing, Sofia! Breanna Mar 18, Wonderopolis Mar 18, We are so glad that you enjoyed this Wonder!
Reyna's 4th Grade Homeroo Sep 18, How are the babies fed if they can't reach? Do they nuzzle each other to show affection? We see this on cards all of the time : And what is with their pattern? It is similar to a leopard's and makes us think they are mimicking. We are really wondering this morning!
Wonderopolis Sep 19, Stringer's 4th Grade Home We are still wondering about why giraffes fight other giraffes and how big a giraffe baby could be. We were also thinking about the similarities between a giraffe and some long necked dinosaurs Casimiro Apr 17, Well, they have long necks because they reach their food in the trees. The giraffe only lives to be about 25 years old.
The horns on the giraffe's head are not for defense. It uses it to push the branches out of the way so they can get more food. Wonderopolis Apr 17, Pruetz's 4th Grade Orange Apr 20, Wonderopolis, Thank you very much for providing this wonderful video about giraffes. We had a lot of fun and enjoyed our time learning. Pruetz's 4th Grade Orange Group. Wonderopolis Apr 20, Team McNeil 9 Apr 17, Hi Wonderopolis! I was very interested when I found this topic! I love giraffes! One new fact that I learned was that giraffes fight by beating each other with their heads and necks, and that this process is called "necking".
I also didn't know that giraffes have a deadly kick, and that they can run up to 30 miles per hour!! I also learned two knew vocabulary words! One is drought, which means that there is hardly any water or rain in an area. Another vocabulary word that I learned was scarce, which means that a natural resource, animal species, etc Campbell's 5th Grade Yell Apr 17, Wonderopolis, We are students at Condit Elementary and we are in the fifth grade yellow group.
We enjoyed reading and listening to the information about giraffes. We generated a list of questions and voted for one more thing to find out about giraffes. We would like to know if there is an animal that the giraffe is thought to have evolved from? Campbell's Fifth Grade Yellow Group.
Campbell's 4th Grade Yell Wonderopolis, Our fourth grade yellow group also enjoyed your information on giraffes. They had some questions about giraffes around the world too. We would like to know how tall and heavy the largest giraffe in all of history has been? Campbell's fourth grade yellow group. Campbell Apr 12, Wonderopolis, We enjoyed your post about giraffes.
We all had some questions that were not answered in your video and we voted on one to ask you. We are curious to know more information about a giraffe's heart. Is it bigger than a human heart? We know that the heart gives out after about 25 years, but we wonder if it proportionately bigger than our heart? Wonderopolis Apr 12, Megan Apr 10, Thanks for a great wonder. Giraffes are my favorite animal, but I think more could of been in the article!
Wonderopolis Apr 10, Team Unger 8 Mar 29, In this article, I learned some new facts about giraffes. One of them is that they can run 30 miles per hour! Another thing I learned is that their necks reach more than 7 feet tall! Also I learned what necking is-when they fight. Finally, I learned the word foliage. I do have one question; how long are the young giraffes necks when they are born?
Thanks for making me wonder! Wonderopolis Mar 29, Bob Mar 23, Wonderopolis Mar 24, Kamryn Mar 15, Wonderopolis Mar 15, They're pretty awesome, Kamryn, we agree! Landon Mar 12, Giraffes have long necks because they use them to eat leaves. I also noticed that they have long legs, long tongues and long tails.
Wonderopolis Mar 12, Carry Mar 10, If I had a long neck, I don't know what I would do with it, but somehow giraffes use them! I really enjoyed this wonder today! Bye for now, I'm going to comment on the wonder of the day!
Wonderopolis Mar 10, Alex Mar 8, I think giraffes have long necks so they can get leaves from trees. Wonderopolis Mar 8, Wonderopolis Mar 7, Way to go! Flinn's Kindergarten Class Mar 5, We are still wondering how tall a teenager giraffe is? How long are girl giraffes? We learned giraffes are 15 feet tall. Giraffes kick and bend necks when they see predators. Giraffes have long necks to see predators. Giraffes are the tallest land animals in the world. Wonderopolis Mar 5, Good Wonder!!
This made my brother think why giraffes have long necks! Thanks very much! Wonderopolis Mar 3, Paige Mar 2, Dear Wonderopolis, Cool wonder!
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