Antlers refers to the extension of the skull that is usually grown by the male elk. The antlers normally grow in a symmetrical fashion, extending in all direction. The major function of the antlers in the male elk is sexual attraction, the antlers are used by males to attract females for sexual reproduction. The antler is also used as weapon in fighting especially fighting over females.
Large antler in elk give a distinctive reproductive advantage to a male because a male with a large antler will be more likely to succeed when it come to male to male battle competition for female and also female mate choice [a female will naturally prefer a male with large antlers].