Natural versus Cropped Ears
Many images of Great Danes show them with upright (cropped) ears. Many people are unaware that there is a medical procedure required to get the ears to look like this. It is illegal in most countries. The USA is one of the countries where it is still allowed. It is banned in South Africa.
Great Dane ear cropping is a veterinary procedure involving the removal of part or all of the pinnae, or the externally visible flap of the ear, on a dog. During the surgery, the floppy part of the dog’s ear is surgically removed. Afterward, care involves pinning the ears up in efforts of achieving a pointed appearance. (https://greatdanecare.com/great-dane-ear-cropping-101/)
Ear cropping is an ancient practice and was first seen in Great Danes when the breed was used primarily to hunt wild boar in Europe. The ears were cut smaller to prevent them being cut and torn by the boar or branches and undergrowth.
Since ear cropping no longer serves the purpose of protecting against other animals while hunting, cropping ears nowadays is merely a personal preference in certain countries.
If you see a cropped Dane in South Africa it was probably imported already cropped.