The giraffe's neck and natural selection?

Question

The usual explanation is about reaching branches but it seems more likely that the increased visual range for predators or promising feeding sites might have been relevant. Any thoughts?

Answer 1

Well.. Mose People Think That The Giraffe Has More Bones In Its Neck That Any Other Animal. But The Have The Same Number Of Bones In Their Necks As Humans! Unbelieveable I Know.

Anyway.. Having A Long Neck Has Both Advantages And Disadvantages. Advantage Because The Can See Ememies From A Further Distance Than Other Animals But A Disadvantage Because The Neck Is Heavy So The Cant Run That Fast.

Answer 2

your thought is actually Lamark's belief. Darwin felt that there were both long and short neck giraffes. The short neck giraffe died off from not being able to reach its food source while the long neck giraffe survived. "Survival of the fittest".

Answer 3

yep you answered your own question.

Any form of advantage like seeing predators, access to food etc would be passed down, because the animal is still alive to breed.

Answer 4

I'd say they have a long neck to reach branches. It's an advantage for them to reach vegetation in a generally dry environment.

Answer 5

It is a combination of all hose factors you mention.  The .....buck (forgot its name) is also a tree browser, but did nor evolve a long neck, but on the other hand can stand on its hind legs. I think that when you evolve one part of your anatomy, for whatever reasons, others reasons will also come to the fore. There is also a possibility that there are disadvantages too.

Peace.

Answer 6

Actually, the long neck of the giraffe is primarily a result of sexual selection.

Giraffes compete for mates through a ritual combat system known as 'necking' - in which males slam and wrestle each other by swinging their powerful necks at each other.  The strongest and longest necked males usually win, and get to mate, and pass their genes for long, powerful necks on to their offspring.

The ability to reach branches and see predators is an off-shoot benefit of this system, which reinforces the selective advantage of the trait.

Answer 7

Actually, there is another possible explanation: as giraffes evolved longer LEGS (in order to be able to browse higher than other herbivores, move faster and, perhaps, to see further over the savannah to spot predators or potential mates) they also had to evolve longer necks in order to drink without having to lower their entire bodies, which would make them vulnerable to attack by aforementioned predators (specifically, lions/lionesses).

Answer 8

Both are a great answer, but predators normally alert some other type of animal that the giraffe stays with, so it's really for eating and getting the branches

Answer 9

bmac doesn't understand Lamark, who postulated that the giraffe's neck got longer from generations of them having to stretch higher and higher for food. This sort of 'forced evolution' has been shown to be not the case, however.

As for the original question, as giraffes evolved in the somewhat open savannas of Africa, being able to spot predators, food sources is probably of secondary importance. Once they got to a certain height, any additional may not have been much more help. Full-grown giraffes are such large animals anyway that few predators will take one on because of possible injury from the hooves.

The 'necking' behavior probably evolved after the neck reached such heights, since there isn't any other way for giraffes to effectively combat. They don't have much in the way of horns, and they're too big and bulky to rear up and use their hooves on each other.