theory. What would be the point of males continually increasing in size if females were still able to obtain food at their smaller size? Another factor affecting Darwin's theory is that the giraffes in the Serengeti spend most of the dry season feeding from low bushes and during the wet season, they eat from the tall trees where the new leaves are plentiful (Simmons 775). This information points out that the main idea behind Darwin's theory is false. During the dry season, giraffes are not more likely to eat food from higher trees, the opposite is true. Therefore, there is no direct advantage for the sexes to have their long necks because most of the time they do not feed at a higher level. Females were especially more likely to eat below the shoulder level, but males also feed regularly from below or at that level. If necks had evolved solely for food competition, there would be serious consequences in the event of a drought. Male giraffes are on average two feet taller than females, indicating that the females would be selected against during a rougher climate year (Brownlee 1022). When fossils were observed, it appears that selection actually "favored heavier bodies and large, heavy necks" (Simmons 776). There was no direct evidence that indicated that elongation had taken place. This information points out another flaw in the original theory about giraffes and the evolution of their necks. Instead of selection occurring throughout the body, it appears to be based specifically on the neck. One problem with the sexual selection theory presented by Simmons and Scheepers is that it too does not offer a viable explanation as to the reason that females also have long necks. If the necks evolved for sexual selection, there would be no reason for females to also have larger necks: they are not involved in competition and necking does not occur between them. The two scientists offer alternate theories as to why female necks al...
