Carnivora: The Incredible Cousins of Cats and Dogs, Part 1

Red panda at the Duisburger Zoo in Germany. Photo by Mathias Appel.

Red panda (Ailurus fulgens) at the Duisburger Zoo in Germany. Photo by Mathias Appel. Licensed under CC0 0.1.

Our beloved cats and dogs are cousins to some of the fiercest and most skilled predators in the world- the animals of the Carnivora order! While it’s easy to imagine a jungle jaguar kin to a house cat, it’s a bit of a stretch to imagine a grizzly bear cousin to a little lap dog. Yet both are true! Carnivans, as animals in this order are called, are so numerous and specialized, we’ll cover only a few of them in this 4-part series just to skim the highlights! Parts 1 and 2 will explore dogs’ cousins, Part 3 cats’ cousins and Part 4 the evolutionary drivers that play important roles in such variations.

While the name Carnivora suggests all these animals are meat-eaters, it’s more accurate to say they’re omnivores who eat a bit of everything. There are a few purely meat-eating carnivans and a few who tend to be vegan. Of course, there are many meat-eaters not in this group, like humans, sharks and Venus flytraps. But generally, the members of the Carnivora order are meat-eating predators. Predators are essential for maintaining population balance of species who multiply rapidly and in great numbers, like rodents and rabbits.

The Carnivora family tree split into two distinct branches about 43 million years ago: the dog-like branch of the Caniformia, and the cat-like branch of the Feliformia. The dog-like Caniformia suborder branches into nine distinct families still in existence. Here’s a portion of the Carnivora family tree to help you track our journey.

Carnivora Family Tree, Part 1. Illustration by Jeannette Chiappone.

Carnivora Family Tree, Part 1. Illustration by Jeannette Chiappone.

Let’s begin with our dog’s own family, the Canidae.

The Canidae Family: Dogs, Wolves and Foxes

Dogs are members of the wolf, coyote, jackal and fox family, the Canidae. The first of these animals lived around 10 million years ago. Modern domestic dogs, descended from gray wolves, were domesticated by humans between 20,000 and 40,000 years ago.

Today, there are over 20 distinct species of wolves, coyotes and jackals, and 17 species of foxes. These diverse hunters are found in nature in every corner of the globe, except Antartica. In Australia, the only indigenous carnivans are the dingoes.

Canids, as members of this family are called, are characterized by long legs, pointy-snouts and bushy tails. Like all the carnivans, they have teeth capable of puncturing and shearing flesh, and even breaking bones. These hunters have an extra long snouts because they have so many teeth. Dogs, for example, have 42 teeth. Compared to humans who have 32 teeth, or only 28 if they’ve had their wisdom teeth removed, dogs have as many as 50% more teeth than we do! They have considerable claws, too, but since they don’t retract, they wear down and are not as deadly as cats’ claws.

Fennec fox (Vulpes zerda). Photo by Dean Thorpe.

Fennec fox (Vulpes zerda). Photo by Dean Thorpe. Licensed under CC BY 2.0 per AnimalGalleries.org

Dogs and wolves form packs to increase their hunting power and efficiency. Other members of this family tend to hunt solo. Generally, the smaller the hunter, the smaller the prey, although there are some big exceptions.

The smallest of all the Canids is the fennec fox, native to the deserts of North Africa. Adults fennec foxes are about one foot long, not including their tails, and weigh about three pounds. These tiny foxes have enormous, heat-disipating ears, which also hear the tiniest sounds of prey in the vast, desert dunes. They live in connecting family dens dug underground where they stay during the day to avoid the brutal heat. At night, fennec foxes leave their cool dens to hunt, using their huge ears to locate mice, insects, and small birds. But these little hunters also love fruit, as all foxes do, and often dine on fallen dates from palm trees.

One exception to the rule of thumb that animals hunt prey smaller than themselves is that of the great gray wolf, the largest of the non-domesticated canids. While their size varies depending on the region of the world it lives in, adult males are about 3 feet long and weigh about 95 pounds, and the females about 75 pounds. These powerfully built creatures are the only canids to live in both Eastern and Western hemispheres. The gray wolf has been so successful in the past that there are 38 subspecies of this magnificent hunter. While the gray wolf is well known and much feared among humans, unless it has rabies, it rarely attacks people.

Gray Wolf (Canis lupus) at Seney National Wildlife Refuge, Michigan. Photo courtesy of Seney National Wildlife Refuge.

Female gray wolf (Canis lupus), Seney National Wildlife Refuge, Michigan. Photo courtesy of Seney National Wildlife Refuge, under CC BY 2.0.

Surprisingly, gray wolves don’t have the extraordinary sense of smell that domesticated hunting dogs do. Like fennec foxes, wolves rely on their finely tuned hearing to listen for rustling sounds of their prey. The success of wolves is, in part, due to their cooperative hunting skills in packs. Lone wolves are known to be astounding hunters, too, but a pack of wolves are rarely defeated by any prey. Sometimes, though, it’s just easier for them to snatch a catch away from some other predatory animal. Wolves hunt everything from beavers, goats, sheep, and deer, to caribou and moose, which are easily 10 times larger than they are.

Wolves, coyotes and foxes sometimes prey on farm poultry and livestock, but generally prefer to hunt in the wild. Farmers, ranchers and bounty hunters have killed these Canids for centuries to protect their stock and their livelihoods, even though harm from Canids is rare and negligible.

Unfortunately, human’s hunting success has cost these animals dearly. By 1933, bounty hunters had killed nearly all the wolves in the United States. The remaining few were finally protected in 1974 by The Endangered Species Act. Today, the Gray Wolf, two other wolf species and two fox species are listed as endangered. Thanks to these protections, their numbers are rebounding. Still, their ultimate fate hangs in the balance. To learn more about the status of wolves, check out this Earthjustice article.

It’s important to remember that complex ecosystems evolved with predators as critical actors in maintaining nature’s delicate balance. The video below, courtesy of Sustainable Human, describes the biodiversity explosion and restoration of the ecosystem that occurred when gray wolves were reintroduced into Yellowstone National Park.

(If you’re interested in how feedback loops work in complex systems, such as how the wolf’s presence altered the Yellowstone ecosystem, you can learn more in The Edge of Chaos: Using Systems Theory to Rock The Word!)

These incredible hunters have interacted with humans so long, that they are woven into the folklore and  mythology of peoples all over the globe. Their cousins, the bears, are also fierce but beloved actors on nature’s stage.

Bears: A Small and Dwindling Family

Yes, dogs and bears are cousins, though quite distant, indeed. Their last common ancestor lived about 40 million years ago. Still, they share many of the same characteristics, such as long snouts full of meat-shearing teeth, thick fur and non-retractable claws. Bears are much larger than Canids. In fact, they’re the second largest animals in the Carnivora order. (We’ll meet the largest in Part 2!) Bears also have short legs, tiny tails, small ears, and a completely different way of using their feet to get around.

Unlike dogs and wolves, who walk on the balls of their feet, bears walk with their heels down, similar to humans. This provides them with a stable platform to easily stand up and even walk steadily on two legs, though a bit clumsily.

Sun Bear (Helarctos malayanus), Alma Park Zoo, Brisbane, Australia. Photo by Andrew Napier.

Sun bear (Helarctos malayanus), Alma Park Zoo, Brisbane, Australia. Photo by Andrew Napier. Licensed under CC BY 2.0.

Bears can be found all over the world, from the tropics to the frozen tundra, yet there are only eight species of them in existence! Compared with many of the families in the Carnivora order, such a small family is quite unusual. Among their members are brown bears (which includes the subspecies of grizzlies), polar bears, black bears and giant panda bears.

The smallest of the bears is the sun bear of the jungles of Southeast Asia. Sun bears are named for the unique marking of gold or orange fur around their necks, which some say looks like a collar of sunshine. These diminutive bears measure less than 3 feet long and weigh in at about 150 pounds. Their diet consists of lizards, small mammals, insects, and what every respectable bear loves best- honey! Unfortunately, because of widespread deforestation in Southeast Asia, habitat loss for the sun bears has led to a sharp decline in their numbers. The sun bear is classified as a vulnerable species.

The largest bear is the polar bear, though the Kodiak brown bear is close in size. The polar bear lives within the frigid landscape of the Arctic Circle. An average male polar bear measures eight feet in length and can weigh as much as 1,500 pounds! Female polar bears are about half that size.

While these denizens of the Arctic have white fur to blend in with their snowy surroundings, their skin underneath is black to absorb the heat from sunshine. They need this because, unlike many marine mammals, polar bears have no special layer of insulating blubber. Their black skin, together with extra thick and water-repellent fur does the trick to keep polar bears toasty, even in the coldest of Arctic winters

Pair of Polar Bears (Ursus maritimus). Photo by Gary Kramer, courtesy of US Fish and Wildlife Service.

Pair of polar bears (Ursus maritimus). Photo by Gary Kramer, US Fish and Wildlife Service. Licensed under CC BY 2.0.

Polar bears have highly selective tastes. They hunt almost exclusively seals. Although polar bears are excellent swimmers, they don’t hunt seals underwater. Instead, polar bears lie in wait close to breaks in the surface of sea ice. When a seal pokes its head up through the hole to catch its breath, the polar bear launches a surprise attack, using its powerful paws to grab the seal and its jaws to pull it onto the ice for the kill.

Unfortunately, much like the sun bears, polar bears are facing widespread destruction of their habitat as the Arctic sea ice melts due to climate change. Several of their populations are in decline and polar bears are now a threatened species.

Another bear with highly selective tastes is the bamboo-nibbling great panda bear. These iconic bears, who live high in the mountains of China’s bamboo forest, subsist mostly on bamboo shoots and leaves. Some occasional rodents, birds and insects round out their diets. Like like the sun bear and the polar bear, the panda’s natural habitat has been dramatically reduced, threatening its survival. In 1988, it was discovered there were fewer than 1,200 Pandas in the wild, a 50% decline from the previous 10 years. A massive Chinese government program to save the beloved bears from extinction has turned the decline into a small and slow comeback. The giant pandas were recently upgraded from endangered to vulnerable.

Another cousin to our beloved dogs is a panda rivaling the adorableness to the giant panda. But it turns out this panda isn’t a bear at all!

The Red Panda: The Last of Its Kind

Red Panda, Ailurus fulgens, Duisburger Zoo, Germany. Photo by Mathias Appel.

Red panda (Ailurus fulgens), Duisburger Zoo, Germany. Photo by Mathias Appel. Licensed under CC0 1.0 .

Yes, the adorable red panda, from the bamboo forests of the Himalayan mountains, is a cousin to our domesticated dogs! It’s the last of a family of carnivores that once numbered 24 distinct species, all now extinct except one. Because of their facial markings and banded tail, the red panda was once thought to be in the raccoon family. It was also surmised to be a relative of the giant panda because of both its markings and its love of bamboo leaves. But DNA analysis shows the red panda, while related to raccoons and pandas, is in its own unique family, which branched off from the Carnivans about 40 million years ago. Fossils from the red panda family have been found across Asia and Europe and even the Bering Strait of North America.

Red pandas are about 2 feet long, not including their bushy tails, and weigh around 10 pounds. With long bodies and short but agile legs, they’re well-adapted to navigate tree branches where they spend most of their lives. Except for mating and females raising her young, Red pandas are solitary and reclusive creatures.

The red panda diet consists largely of of tender bamboo shoots and leaves, but they occasionally hunt small birds and insects. Unfortunately, their dependence on bamboo forests for food and the deforestation of their natural habitats has impacted their ability to survive. Sadly, the red panda is an Endangered Species. Many international programs work to protect bamboo forest habitats where they live. Fortunately, red pandas have adapted well to living in captivity. Captive breeding programs have been hugely successful and the red panda numbers have stabilized.

The magnificent animals of the wolf, bear and red panda families live all over the globe in every imaginable climate. Yet as we’ve learned, even these strong and resilient creatures are facing hunting and loss of habitat that threatens their very existence. Visit the National Resources Defense Council’s website if you’d like to learn more about what you can do to protect them.

In Part 2, we’ll meet cousins of dogs who live our oceans and rivers, and some that will delightfully surprise you!

 

 

 

 

 

 

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2 Responses to Carnivora: The Incredible Cousins of Cats and Dogs, Part 1

  1. Janette Maurer says:

    Explorer science news is some of the best reading around for learning and co-habitating in our Urban and natural environment. Great details and topic and thank you for including the links on how we can participate with these modern day issues

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