Many animals share the deer’s basic body plan: slender legs, herbivorous diets, and a digestive system specialized for fermenting tough plant matter. A true deer is a hoofed, cud-chewing mammal belonging specifically to the family Cervidae. This family is defined by the presence of antlers, which are bony extensions of the skull that are shed and regrown annually by the males of almost all species. Animals that exhibit a deer-like silhouette but belong to a different family are typically artiodactyls, or even-toed ungulates, that have independently developed similar features.
The Unique Pronghorn
The Pronghorn (Antilocapra americana) is a striking example of a deer look-alike, yet it is so genetically distinct that it is the sole surviving member of its own family, Antilocapridae. Often misidentified as an antelope, the Pronghorn shares no close relation with the true antelopes of the Old World, which belong to the Bovidae family. This animal is the fastest land mammal in the Western Hemisphere, capable of reaching sustained speeds of up to 55 to 60 miles per hour.
The Pronghorn’s visual acuity is exceptional, possessing large eyes that grant it a nearly 300-degree field of vision and the ability to spot movement up to four miles away, an adaptation suited for its open grassland habitat. The structure of the Pronghorn’s headgear is the clearest distinction from true deer antlers. Unlike antlers, which are pure bone, the Pronghorn grows a horn consisting of a permanent, bony core covered by a sheath of keratinized hair. The unique feature is that this keratin sheath is shed every year after the breeding season, a trait found in no other animal globally. This sheath also features a forward-pointing projection, giving the horn its characteristic pronged shape.
Tiny Imposters: Chevrotains
The dense tropical forests of Asia and Africa are home to the Chevrotains, also known as mouse-deer, which constitute the family Tragulidae. These diminutive animals are the smallest of all living hoofed mammals, with the smallest species weighing only about four to six pounds, roughly the size of a domestic rabbit. They represent an ancient and primitive lineage of ruminants.
Chevrotains lack any form of head ornamentation, possessing neither antlers nor true horns in either sex. Instead, the males have elongated upper canine teeth that protrude conspicuously from the mouth, resembling small tusks. These canines are used for sparring with rivals over territory or mates, similar to the function of antlers in deer. Their primitive status is confirmed by their skeletal and digestive anatomy, which displays traits closer to non-ruminants like pigs. For instance, their stomach features only three distinct chambers instead of the typical four found in more advanced ruminants, such as true deer.
African Forest Ruminants
The African continent hosts a variety of small antelopes often mistaken for diminutive deer, most notably the Duikers and Dik-Diks, both members of the Bovidae family. True horns are permanent structures composed of a bony core covered by a keratin sheath, which are never shed, setting them apart from the deciduous antlers of the Cervidae family.
Duikers are small, shy antelopes found in the dense bush and forests of sub-Saharan Africa. The name “duiker” comes from the Afrikaans word for “diver,” referring to their habit of escaping predators by plunging, or diving, headfirst into thick vegetation. Their body shape is hunched, with hind legs slightly longer than their forelegs, which facilitates this unique, head-down escape behavior.
Dik-Diks are even smaller, standing only about 12 to 16 inches tall at the shoulder, with their name derived from the whistling alarm call made by the female when sensing danger. Only the males possess small, spike-like horns, which are often partially obscured by a prominent tuft of hair on their forehead. Both Duikers and Dik-Diks use large, dark glands located just below their eyes, called preorbital glands, to secrete a sticky fluid that marks their territory on twigs and grass stems.