Why do Giraffes Have Long Necks?
Many observers of giraffes have noted their extraordinarily long necks, leading to a great deal of speculation about why giraffes have long necks. There are a number of theories, but the most probable explanation is that giraffes with longer necks are more successful in fights, and giraffes which win fights are able to breed. The famous neck of the giraffe has apparently evolved out of a desire to win battles, and centuries of natural selection for longer, thicker necks has led to the modern giraffe.
The long neck of the giraffe is supported with extremely strong anchoring muscles which help the animal keep its head upright. As a result of the evolution of long necks, giraffes have had to make several adaptations to survive, including the development of a very powerful circulatory system which pushes blood from the heart to the brain. Considering the physical stress created by having such a long neck, there's no clear biological advantage for giraffes, as demonstrated by the general lack of long-necked animals in the world.
Some people claim that giraffes have long necks so that they can reach high foliage on trees and shrubs, under the argument that being able to reach high foliage would allow giraffes to access food during drought periods when leaves are scarce. Researchers who studied giraffe feeding patterns found that, in fact, giraffes tend to browse low, lowering their heads to eat. In the wet seasons, when there is a great deal of foliage overhead, giraffes may browse on high leaves.
Other people have suggested that giraffes developed their long necks so that they can clearly see approaching predators. Biologists have largely dismissed this theory, arguing that if being able to see across great distances was such an advantage, more animals would have long legs and necks. While the fact that giraffes have long necks has certainly made it easier to spot predators, it is unlikely that giraffes evolved long necks specifically for this purpose.
Giraffes and many of their relatives fight by essentially beating each other with their necks and heads, in a process known as necking. Male giraffes use their necks like deadly weapons, whipping their necks around and clubbing their opponents with their heavy skulls. The longer and thicker the neck, the more of a punch it packs, so it seems that giraffes have long necks so that they can fight more effectively.
For those who are interested in another factoid about these African mammals, in addition to having lengthy necks, giraffes also have very long tongues. The animals use their tongues to reach around the thorns of acacia trees to reach the leaves without hurting their muzzles.
Answer me this. I am a giraffe and I have decided I should have a longer neck. How do I start that process? By wishing really hard? I also want every giraffe born after me to have longer necks too. I've heard many people say that their necks got longer over time because the food source was higher. So if I raised the basketball hoop in my yard from 10' to 11,' will everybody born after I do be taller in my family?
Actually, Serena, they did find that male giraffes have an average neck length of 7ft and females at 5ft. This further supports the hypothesis.
And, literally45, did you read the article? Several observers followed giraffes through all seasons (drought and wet) and found that they prefer lower bushes over trees.
@serensurface-- Why do giraffes have such long necks? It's actually not a puzzle. We know that it's due to natural selection. The confusion is about why natural selection favored giraffes with longer necks.
Also, if evolutionary theories do not explain it, one could also support the creationist view that God willed it so.
It used to be thought that sexual selection was the cause of long necks in giraffes. But studies have been done on it and no significant difference was found in the neck length of male and female giraffes. Scientists believe that if sexual selection had been the cause, the neck length of males would be longer but that is not the case.
The cause of long necks in giraffes seems to be a puzzle.
There may be many evolutionary reasons as to why giraffes have long necks. Even though the article argues otherwise, I'm also of the view that the long neck allows giraffes to feed off of trees.
I think that nature has a perfect balance. There is a cycle where one living thing feeds off of another and somehow there is such a balance that if an external factor doesn't disrupt it, everything keeps on living. Neither do certain populations of animals, bugs or plants grow in large numbers, neither do they go extinct if this balance is kept.
I'm sure that giraffes contribute to this balance with their long necks and their feeding off of trees.
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