John F. Corbett,III

Bio.335-Wildlife and Fisheries Biology

Keystone College

Feb. 2, 2010

Some of the most specialized and spectacular mammals- horse, rhinoceros and tapirs.

The most abundant ungulates- having hoofs or being odd toed, occurred 33.9 mya.

Common largely in southern areas- Africa, parts of southern and central Asia and tropical parts of southern North America and northern South America.

Ungulates are typically herbivorous.Have exceptional running ability.

Equus zebra zebraMountain zebra

Tapirus terrestrisBrazilian tapir

Certotherium simumWhite rhinoceros

Horse front foot

Tapir front foot

Rhino front foot

Kingdom- Animalia Phylum- Chordata Class- Vertebrata Order- Perissodactyla Family- Equidae Tapiridae RhinocerotidaeThe surviving perissodactylan fauna consists of

6 genera and 17 species.

Ability to synchronize their breathing with their stride cycles.

Phenomenon known as pneumatic stabilization- involves moving air from side to side between lungs to control inhalation and exhalation.

Pressurized lungs help stabilize the large shoulder and chest as the forelimb strikes the ground.

Elongated limbs, elongated metatarsals and metacarpals.

Movable scapula and well developed flexors and extensors in the vertical column for exceptional movement.

Human examples of extensorsand flexors.

Human examples of metacarpalsand metatarsals.

Herbivorous diet has favored the development of cheek teeth with large surfaces that finely break down plant material which aids in digestion.

Herbivore must break down rigid cell wall which is formed largely of cellulose.

Mammals lack enzymes that digest cellulose.Microbial fermentation- digestive process

involving specialized fermentation chambers which aid in the digestion of cellulose.

Must seek sites that support the greatest quantity and most nutritious of vegetation.

Their range is correspondingly restricted.

Evolved in Asia from herbivorous condylarths of the family Pheacodontidae.

Appeared in North America 55.5 mya and underwent rapid diversification.

Teeth and cranial morphology developed in response to herbivorous feeding habits.

Living perissodactyls have elongated skulls to accommodate large set of cheek teeth, some have a complete complement of 44 teeth.

Front foot has 1, 3 or sometimes 4 digits and the hind foot has 3 digits.

Feet are mesaxonic- plane of symmetry of the foot passes through the third digit.

Most highly adapted running and graceful perissodactyls.

Feral populations of domestic horses and burros live in various places, there is 1 genus and 8 living species.

Equids are first represented by Hyracutherium, 55.5 mya in Europe and North America.

Major evolutionary trends… -increase in size -lengthening of legs and feet -reduction in size of lateral toes and emphasis on the middle

toe -increase in height of cheek teeth crowns -lengthening of facial part of skull to accommodate large

cheek teeth

Equids are polygynous animals- 1 male controls access to more than 1 breeding female.

Form large herds consisting of extended family groups or “clans”.

Social hierarchy exists, usually led by a stallion.

Status within group is maintained by complex behavioral and vocal communication.

Wild mustangs of Nevada

Occupy tropical parts of the New World and the Malayan area- south east Asia.

Family includes 1 living genus and 4 species.Ancestral types occurred 55.5 mya in North

America.Stocky build and short limbs.Front feet have 4 digits and hind feet have 3 digits.Short proboscis-snout and reduced nasals.Primitive feet serve well on soft soil of tropical

areas.Rapid swimmers. Take refuge from predators in water.Solitary and nocturnal.

Represented by 4 genera and 5 species which are restricted to parts of tropical and subtropical Africa and south east Asia.

Surviving members from 33.9 mya, which are a declining group.

Stout-bodied herbivores with short, column-like limbs.

Front foot has 3 or 4 digits and hind foot has 3 digits.

Nasal bones are thickened and enlarged which supports a horn that lacks a bony core.

Inhabit grasslands, semi-deserts, savannas, brush land, forests and marshes.

Some species usually solitary, where others occur in family groups or assemblages of up to 24 animals.

Territorial and practice scent marking by establishing dung hills along trail.

Adults are nearly invulnerable to predation but the young are occasionally killed by lions.

Asian and African black rhinoceros are facing extinction.

Have been hunted for at least 1,000 yrs. for their horn which possesses medicinal properties.

Indian rhinoceros populations have recovered from less than 200 to over 2,000 today.

All 5 species of rhinoceros are listed as endangered.

Vaughan, T.A., Ryan, J.M., Czaplewski, N.J., Mammalogy, 4th Edition, 2000, Thomson Learning. Inc., pp. 260-271.

Willis, D.W., Scalet, C.G., Flake, L.D., Introduction to Wildlife and Fisheries-An Integrated Approach, 2nd Edition,2009, W.H. Freeman and Co.

www.tapirback.com -The Tapir Gallerywww.talkorigins.org –Horse evolution sitewww.rhinos-irf.org –International Rhino

Foundation

Thank You