Spotted Zebras, Yellow Cardinals, and Three-Antlered Deer: What Causes these Animal Oddities?

Albinism, extra appendages, unique coat patterns—all are caused by changes in a species’ genetic makeup. Genetic mutations can alter how a species looks, how it behaves, and how its body functions. Whether harmful or beneficial, genetic mutations help make a population diverse and allow for a wide variety of individuals. Below are eight animals spotted in 2019 with genetic mutations that created unique features and characteristics.  

1. Gynandromorphic Cardinal 

A gynandromorphic—meaning half-male, half-female—northern cardinal was spotted in Erie, Pennsylvania, in January 2019. This genetic anomaly is referred to as bilateral gynandromorphism because it causes a split right down the middle with half of the species’ body resembling a male and the other half a female. Gynandromorphism likely occurs because of an error during egg formation. The cardinal not only appears half-male, half-female, but it also has the genetic makeup for both sexes. So, its brain is likely half-male, half-female, too.  

Gynandromorphism is a very rare condition that is known to occur in insects, snakes, crustaceans, and birds. This mutation is likely present across all bird species, but it is harder to detect in a species where adult males and females look similar, Daniel Hooper, a postdoctoral fellow at the Cornell Lab of Ornithology, told National Geographic. Because gynandromorphic birds are so rare, most of what is known about their behavior and the effects of this mutation comes from just one bird—a half-male, half-female northern cardinal found in 2008.

2. Piebald Deer

A piebald white-tailed deer was seen in Cary, North Carolina, last December. Piebaldism is a genetic phenomenon that causes a lack of pigmentation in patches around the body. Piebaldism is a recessive trait, which means both parents must carry the recessive gene for this coat coloration in order for them to produce a piebald offspring. That makes this characteristic very rare, affecting less than two percent of the white-tailed deer population, according to David Osborn, wildlife research coordinator at the University of Georgia Deer Research Facility. 

Piebaldism does not just affect coat coloration. It can also cause an array of possible deformities, including changes to skeletal alignment like short legs and curved spines. Piebaldism also makes deer susceptible to predation as they are easier to see with white coloring. It is illegal to kill albino deer, which lack all pigment and are completely white, in several states, including Illinois, Iowa, and parts of Montana, Tennessee, and Wisconsin. Piebald deer, however, are protected in fewer states, and this protection is often based on how much of the deer’s coat is white. 

 3. Spotted Zebra

A plains zebra foal with a highly unusual dark coat and white polka dots was spotted in Kenya’s Masai Mara National Reserve last September. This zebra, which was named “Tira” after the Maasai guide who found it, had a striking, spotted coat pattern, rather than the trademark white coat with black stripes. Some scientists believe that this coloration is due to a condition called pseudomelanism, a rare genetic mutation that, like albinism, is caused by a disruption in melanin production. With this mutation, melanin is still produced, but it does not manifest correctly as stripes. 

Unfortunately, many zebras with unusual coloration may not survive very long, Ren Larison, a biologist at the University of California, Los Angeles, told National Geographic. A lack of stripes may affect the zebra’s ability to camouflage from predators, regulate temperature, and deter biting flies that carry diseases like equine influenza. 

4. Black Leopard

Another unique animal was seen in Kenya last year at the Laikipia Wilderness Camp—an elusive African black leopard, also known as a black panther. Its distinct coat coloration is caused by a genetic mutation called melanism, which has the opposite effect of albinism. This mutation affects the regulation of melanin, resulting in an overproduction of dark pigments and the black coloration. The only difference between a black leopard and other leopards is the color of its coat. It is not a separate species. Scientists stated that the last confirmed sighting of a black leopard on the African continent was in 1909 in Ethiopia. Melanism is found in about 11 percent of leopards globally, but most of these leopards live in the forested habitats of Southeast Asia.

The leopard’s dark coloration may help it better camouflage at night, warm faster in the sun, and even ward off parasites. But, there is also a major disadvantage of melanism for these big cats. A 2019 study in PLOS ONE suggested that markings critical to feline communication are hidden in melanistic leopards. A black leopard lacks the white markings on its ears and tail that other leopards use to signal to each other. These markings indicate a variety of messages, ranging from friendly signals to “back off!”

“One example is that mother cats can lift their heads and stretch their ears to flash the white marks to signal possible danger to their cubs, or to keep quiet if prey is nearby,” zoologist Maurício Graipel of the Federal University of Santa Catarina in Brazil told Smithsonian Magazine. “But consider a melanistic mother cat with spotted kittens. She could read the kittens’ signals, but they might not be able to see or understand their mother’s. As a result, they may be loud when they need to be quiet, or they may stumble into danger.”

5. “Strawberry” Leopard 

In 2019, another rare leopard was spotted in Africa, as well. A pink-hued or “strawberry” leopard was photographed by a motion sensor camera at the Thaba Tholo Wilderness Reserve in South Africa last July. The leopard, whose unusual reddish pigmentation is known as erythrism, was nicknamed “Goldie” by the owner of Black Leopard Mountain Lodge. Unlike a leopard with melanism, this feline had a coat with light, pink coloration. Erythrism is caused by a rare mutation and very little is known about it. This recessive trait causes either an overproduction of red pigments or an underproduction of dark pigments. The mutation is very uncommon in carnivores and is most often seen in raccoons, badgers, and coyotes, Panthera President Luke Hunter told National Geographic. 

This unique leopard coloration was captured on camera for the first time in 2012 at South Africa’s Madikwe Game Reserve. Luckily, the leopard’s coat still provides some camouflage, allowing it to hide in the grass and ambush prey. Hunter also noted that the leopard found in 2012 seemed healthy and likely suffered no negative effects from its pinkish coloration. 

6. Three-Antlered Deer

A three-antlered white-tailed deer was seen last November in Detroit, Michigan. The deer likely developed an extra antler either because as an embryo, the bud that leads to an antler’s growth separated into two, or once the deer was born, the bud was damaged somehow causing it to split, Steve Edwards of Lakeview Animal Clinic in Michigan told Detroit Free Press. Yet, there are some other ideas about how this third antler was created. If blood supply is restricted for growing antlers, it could result in odd shapes, such as an extra appendage. Alternatively, when deer shed their antlers in early spring, if the previous antlers don’t shed off fully, it could also result in unusual growths on deer—including an antler, John Bruggink, professor of wildlife biology at Northern Michigan University, told The Washington Post. 

“This buck looks totally healthy, and the buck is normal,” Edwards said about the three-antlered deer. He also stated that this deer was likely a “one-in-a-million” find. There have been reports of deer with extra antlers as early as 1965. 

Deer antlers are rather heavy, weighing between three and nine pounds, but Bruggink predicted that the extra antler did not cause the buck any harm. Antlers, however, may serve as a visual cue signaling health and genetic quality to female deer and are used to assert dominance between males. So, the extra one could impact the deer’s ability to find a mate. 

7. Yellow Northern Cardinal 

Another “one-in-a-million” find was spotted last October in Port St. Lucie, Florida—a yellow northern cardinal. This unique cardinal, aptly nicknamed “Sunny,” gets its yellow coloration from a genetic mutation called xanthochromism, which is similar to albinism. This mutation knocked out, or shut off, the redness pathway in the bird’s DNA, blocking the normal red coloring and causing an excessive production of yellow pigment. Roughly three yellow cardinals are reported each year, making this bird sighting a “one-in-a-million” find, according to Geoffrey Hill, a professor and curator of birds at Auburn University and an expert on bird coloration. Yellow cardinals make up well below one percent of the total northern cardinal population, and finding a male cardinal with that yellow pigment is extremely rare, Thomas Webber, a collection manager of the Division of Ornithology at the Florida Museum in Gainesville, told Treasure Coast Newspapers.  

It is not well known whether birds with xanthochromism face an increased risk of predation, plumage deterioration, or physiological problems as albinistic birds do. Research has shown, however, that as bird plumage becomes seasonally brighter and more conspicuous, birds change their behavior, such as fleeing more frequently, to be cautious and avoid predation.

8. Black Coyote 

A black coyote was found in Austin, Texas, last October. The Austin Animal Center said the coyote’s black coat is believed to come from hybridization with domestic dogs. Hybridization is the process when two individuals from different species reproduce, allowing traits from one species’ genetic background to integrate with traits from the other species. Scott Chambers, curator at the Austin Zoo, believes that this hybridization, or breeding with another dark-colored coyote, caused the mutation that allows for melanism—the same condition found in the black leopard. Wildlife officials at the Austin Animal Center set up motion sensor cameras after receiving reports in July that there was a black coyote. The camera caught photographs of the black coyote in Austin, along with images of its three pups and mate.

Chambers told Fox7 that black coyotes are rare, but melanism is fairly common in nature. Melanism is occasionally seen in coyotes found in the Southeast, but is rarely exhibited by coyotes in other regions of the United States. This dark coloration may help coyotes better camouflage in forested habitats while hunting, as well as help regulate body temperature. 

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Animal oddities are not only shocking and intriguing, but they also remind us of the beauty of biodiversity. Biodiversity is vital for the survival of wildlife and ecosystems across the United States and plays an important role in our own lives. It provides us with an array of foods and materials and contributes economic and ecological services that allow us to live healthy and happy lives. These services include everything from cleaning water and capturing carbon to providing oxygen for us to breathe.

But, biodiversity is at great risk because of the wildlife crisis we are facing. One-third of all U.S. wildlife species are already imperiled or vulnerable—and nearly one million species worldwide are at risk of extinction. Habitat loss, climate change, invasive species, disease, and severe weather have all taken a drastic toll on a wide array of species across the globe. 

Our leaders must demonstrate that they understand the importance of preserving biodiversity by taking this extinction crisis seriously while there is still time to have a lasting, positive impact on the state of our planet’s wildlife. 

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