It’s thought that aquatic elephant ancestors had a snorkel-like organ to help them breathe when swimming. This organ became more specialised to help the animal feed over time and now exists as the long trunk we know.
Over 30 million years an animal that lived in water like a hippo but had a trunk like a tapir became a terrestrial elephant with the most impressive nose in nature.
The traits an animal has are passed on to its offspring. Those with traits that are beneficial to survival tend to have more offspring, meaning their traits are passed on to more of the next generation. For example, elephants rely on being able to reach food with their trunks. Those with longer trunks are better at reaching distant veggies, and those with shorter trunks may have difficulty getting hold of food.
This means that over time, elephants with longer trunks generally survive long enough to have more offspring than weaker members of the species. An elephant needs to eat enough vegetation to sustain its body weight and have enough energy to live, play and run from predators. The trunk helps the animal to eat more than it could with the mouth alone and gives it access to better quality food sources.
This is probably the driving force behind the evolution of the trunk, and as they evolved to have larger tusks for defence, the trunk also grew.
The elephant’s elongated nose has a tip as sensitive as human lips. It contains 40,000 muscles and can lift items almost five per-cent of the elephant’s body weight.
Image from www.flickr.com/photos/stuutje