Scientists say they now understand why elephants evolved such long trunks.
According to a study in the journal Acta Zoologica, trunks help elephants to eat more than they would otherwise manage given the size of their mouths and the shape of their skulls.
The elephants' trunks were found to increase the volume of plant material they were able to hold in their mouths.
A South-African based team of researchers led by Yolanda Pretorius and Willem F de Boer came to these conclusions while investigating how plants shaped the development of herbivores' mouths.
The researchers found that, without their trunks, elephants would not eat enough to sustain their size.
The study also noted that the long tongues of giraffes had a similar purpose and origin.