Despite its length, the neck of giraffes is composed of only 7 cervical vertebrae like most mammals. It would result from conserved random genetic mutations. Giraffes with abnormally large and very flexible necks could reach food sources, for example branches of acacia, untapped because out of reach of other animals. No longer having to fight for food, these long-necked giraffes were able to live longer, reproduce more easily and settle permanently while specimens struggling with other species gradually disappeared.