Lecture 15 - Carnivora

Order Carnviora

• Most diverse mammalian order in size.

• Evolved about 55 MYA during the late Paleocene in North America.

  • Split into cat-like and dog-like forms around 40 MYA.

• Eating meat is not a defining character of the order.

• Living carnivorans share morphological characteristics such as specialization of the teeth.

• Individuals may be solitary or paired in groups.

Order Carnivora - Suborders

1. Feliformia - “cat-like”

2. Caniformia - “dog-like”

Hunting methods

1. Concealment (spots or stripes) with a surprise ambush (felids)

2. Stalk followed by a short, swift run (weasels)

3. Prolonged chase (wolves or hyenas)

Teeth specialization

The defining morphological characteristic of carnivores is the carnassial teeth (shearing and cutting).

• Consist of the fourth upper premolar (P4) and first lower molar (M1).

Skulls

• Heavy with strong facial musculature for: crushing, cutting, and chewing flesh, ligaments, and bone

• Felid skulls have a short, rounded rostrum (snout) while Canid skulls have a long rostrum.

• Carnivores often have a deep, sharply defined C-shaped mandibular fossa (hinge joint).

The auditory bullae

The bony structure that houses the inner and middle ear components.

• The structure of the bullae is used to distinguish the 2 suborders of carnivores.

• In feliformes: the tympanic and endotympanic bones form the bullae with a septum.

• In caniforms: the bullae are formed only from the tympanic bone and there is no septum.

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Carnivores stomachs

Carnivores tend to have simple stomachs (with an undeveloped cecum), because meat is easy to digest.

• There are some specialized diets.

• Most only eat living prey, but canids, ursids, and hyaenids also consume carrion (carcass).

Suborder Feliformia

Consists of 6 families.

1. Felidae - cats

2. Hyaneidae - hyenas

3. Herpestidae - mongooses

4. Viverridae - civets and genets

5. Eupleridae - Madagascar mongooses

6. Nandiniidae - African palm civet

Suborder Feliformia characteristics

• Coats that are spotted, rossetted, or striped.

• Found in tropical habitats, with a few exceptions.

• Many are arboreal or semi-arboreal.

• Majority are digitigrade (walk on the toes).

• Felid claws are retractile (rarely semi-retractile).

• Usually strict carnivores.

• Have fewer teeth and shorter skulls.

• Specialized carnassials.

Suborder Feliformia - Family Felidae

The cats.

• The strictest carnivores of order Carnivora.

• Two subfamilies:

  • Pantherinae - tigers, lions, jaguars, and leopards.

  • Felinae - cougar, cheeta, serval, lynes, caracal, ocelet, and domestic cats.

• All wild felids, other than the lion, are solitary.

• Felids are often nocturnal.

• Native to every continent except Australia and Antartica.

• Good binocular vision.

• Tongues are covered with horny papillae, which help to rip meat off of their prey.

• Almost all felids have fully protractile claws.

• Cats have five toes on their forefeet and four on their hindfeet.

Suborder Feliformia - Family Hyaenidae

The hyenas.

• Native to both African and Asian continents.

• Consist of 4 living species - the striped hyena, brown hyena, spotted hyena, and the aardwolf.

• Have bone-crushing teeth.

• Spotted hyenas have powerful carnassial teeth. The aardwolfs have reduced cheek teeth.

• Digitigrade, with non-retractable claws.

• Long necks with long forelimbs and short hindlimbs.

• Lack a baculum (bone found in penis).

• Spotted hyenas live in a hierarchical social structure.

Suborder Feliformia - Family Herpestidae

The mongooses.

• Mongooses are from southern Eurasia and mainland Africa.

• Some species live solitary lives while others travel in groups.

• The meerkats live in troops, with an alpha female and male. They are also diurnal.

• Feed on insects, crabs, earthworms, lizards, snakes, chickens, and rodents.

Suborder Feliformia - Family Viverridae

The civets, genets, and bearcats.

• Among the most primitive families of order carnivora.

• Resemble long-nosed cats.

• Have excellent hearing and vision, and relatively undeveloped carnassial teeth.

Suborder Feliformia - Family Eupleridae

Malagasy carnivores.

• The 8 living species of Madagascar mongoose evolved from one ancestral species.

• Mongooses are their closest living relatives.

• The fossa is the largest mammalian carnivore in Madagascar.

Suborder Feliformia - Family Nandiniidae

African palm civet.

• Has short legs, small ears, and a body resembling a cat, along with a tail that is as long as its body.

• It typically inhabits trees.

• Is omnivorous.

Suborder Caniformia

Consist of 9 families.

1. Canidae - dogs.

2. Mustelidae - weasels, otters, badgers.

3. Mephitidae - skunks.

4. Procyonidae - raccoon, coati.

5. Ursidae - bears.

6. Ailuridae - red panda.

Superfamily: Pinnipedia

7. Phocidae - seals.

8. Otariidae - eared seals.

9. Odobenidae - walrus.

Suborder Caniformia characteristics

• Non-retractile claws.

• More premolars and molars in an elongated skull.

• Less specialized carnassial teeth.

• Varied diets, most tend to be omnivorous.

• All species other than the canidae, and a few of the Mustelidae are plantigrade.

• Most are terrestrial.

Suborder Caniformia - Family Canidae

Dogs.

• Includes the carnivorous and omnivorous wolves, foxes, jackals, coyotes, and domestic dogs.

• Basal Caninae - primitive; 2 species.

• Tribe Canini - “wolf-like” or “dog-like”.

• Tribe Vulpini - foxes.

• Wild canids are on every continent except for Antartica.

• Have relatively long legs.

• All are digitigrade, possess bushy tails, non-retractile claws, and a dewclaw on the front feet.

• Have an elongated rostrum with well developed canines and carnassials.

Suborder Caniformia - Family Mustelidae

Weasels, otters, and badgers.

• Vary greatly in size and behavior.

• Most reproduction involved induced ovulation and delayed implantation.

• Usually small animals with short legs, short rounded ears, and thick fur.

• Digitigrade with non-retractile claws.

• Solitary and nocturnal.

• Have anal scent glands.

• All have strong carnassials.

Suborder Caniformia - Family Mephitidae

Skunks and stink badgers.

• Skunks are omnivorous, with diet changes occurring as the seasons change. They eat larvae, earthworms, small rodents, lizards, frogs, snakes, and more.

• Skunks are nocturnal and solitary.

• They shelter in burrows they dig.

• Excellent senses of smell and hearing, but poor vision.

• They have 2 anal glands that produce a mixture of sulfur-containing chemicals (mercaptans).

Suborder Caniformia - Family Procyonidae

Racoons, coati, and kinkajous.

• A new world family.

• Inhabit a wide range of environments, usually near water.

• Usually omnivorous.

• Smallish, with slender bodies and long tails.

• All, except for the kinkajou, have banded tails, and distinct facial markings.

• Procyonids are plantigrade.

Suborder Caniformia - Family Ursidae

Bears.

• Only 8 living species of bear.

• Non retractile claws and plantigrade paws.

• The giant panda and red panda have an enlarged bone called the pseudo thumb which helps them grip the bamboo shoots.

• Species:

  • Polar bear

  • Giant panda

  • Spectacled bear

  • Brown bear

  • Black bear

  • Sloth bear

  • Sun bear

  • Asiatic black bear (moon bear)

Suborder Caniformia - Family Ailuridae

Red pandas.

• Small arboreal mammals slightly larger than the size of a domestic cat.

• Mainly eat bamboo but are omnivorous.

• Solitary and nocturnal.

Superfamily Pinnipedia

The fin-footed mammals.

• Includes 3 families:

1. Phocidae - seals

2. Otariidae - eared seals.

3. Odobenidae - walrus.

• Medium to large aquatic mammals.

• Thick layer of insulating blubber, typically covered with coarse hair.

• Digits are not separate, but are transformed into paddles.

• Pinnae (external portions of the outer ear) are very small or lacking.

• Vibrissae are well developed.

• Molariform teeth are mostly homodont with well developed canines.

• Carnivorous.

Suborder Caniformia - Family Phocidae

Seals.

• Fore-flippers are used primarily for steering, while hind flippers are bound to the pelvis in such a way that they cannot bring them under their body to walk on them. This is why they are wiggly on land.

• Are generalist predators.

Suborder Caniformia - Family Otariidae

Eared seals.

• Adapted to a semi-aquatic lifestyle, feeding and migrating in the water but breeding and resting on land or ice.

• Breed primarily on land.

• Have more of a dog-like head, sharp, well-developed canines and visible external pinnae.

• Carnivorous.

• Some species of otariid have some of the most extreme cases of sexual dimorphism with males being 8 times the size of the female.

Suborder Caniformia - Family Odobenidae

Walrus.

• Have an abundance of vibrissae surrounding the top of its mouth.

• Sparsely covered with fur and appears bald.

• The skin and blubber layers are thick.

• Walruses can turn their rear flippers forward and move on all fours.

• Have long tusks. These are elongated canines, which are present in both sexes. Have relatively few other teeth.

• Are not deep divers.