"Dork deer" is a term for a deer whose upper jaw is considerably longer than its lower jaw, producing a pronounced overbite. Some also have jaws that are skewed to the side. These animals have an unusual appearance this is often remarked upon by hunters or nature watchers. This trait is generally assumed to be genetic and inherited.
Also Known As:
- Parrot jaw, parrot mouth, bird face, overbite.
It has been suggested that more and more of these deer are been seen, hunted and brought into taxidermists. Observers have suggested that this is due to the proliferation of an abnormal gene in certain populations, or inbreeding.
This deformity is know to occur in reindeer when the deer are selectively bred for white or spotted coats. And some people suspect chemical contaminants may be implicated in increased underbite rates and other deformities.
The technical term for this condition is brachygnathy inferior (abnormally short lower jaw). It is a congenital deformity cause by a number of different genes, and shown in many different deer species. This condition also occurs in a range of other species include sheep, cattle and even the rhinoceros.
- Robinette & Aldous (1955) Parrot mouth is recorded in mule deer (see also: Short 1964).
- Smits (1990) documented brachygnathia on a captive herd in Ontario. This case seems to have a different cause: osteoporosis. The appearance of these deer was much more extreme with very short jaws and protruding tongue.
- Chapman (1992) described a case of brachygnathia and abnormal coloring in a fallow deer fawn.
- Rollor (1993) described a case of brachygnathia and leg deformities in a white-tailed deer fawn.
- Scanlon (1997) observed white tail deer with brachygnathia and leg abnormalities in Virginia.
- Zachos et al (2007) studied an isolated population of red deer in Germany were many individuals has shortened lower jaws, other deformities such as a fawn born without eyes, and demonstrable loss of genetic variability due to inbreeding.
- Haas et al (2012) showed that brachygnathia is occurring at a high rate in a range of deer species.
The occurrence of "dork deer" in many different isolated populations of deer, from different species, indicates that its primary cause is high levels of inbreeding. Deer tend to be part of increasingly fragmented and isolated groups, so inbreeding is occurring at increasing rates. Thus the impression that there are more dork deer around may be entirely accurate.
- The Official Dork Deer thread
Taxidermy Net Forum interactive bulletin board for the taxidermy industry, with over 10,000 unique visitors each day.
White and piebald deer also often have a shortened lower jaw and other facial deformities.
This is logical as pale coat color, a.k.a. leucism, is a recessive trait and also associated with inbreeding.
Request for Pictures
If you have any pictures of dork deer that I could use to illustrate this hub please send them to me at psycheskinner at gmail.com. Thanks to Andy Lott, Matthew White, and David Wigley for pictures contributed so far.