Classification of Cetaceans | Aquatic Mammals

Division of the Order:

Suborder (i) Archaeoceti:

This suborder includes primitive or first whales, the fossil forms of which have been found in the sedi­ments of mideocene. They were large attaining a length of about 18.25 cm. The tail was very long. The forelimbs were modified into paddles.

The hind limbs were ill-developed. The skull was more primi­tive than that of latter whales. The facial bones were not telescoped into the back of the skull. The teeth were 44 in number.

The incisors and canines were simple and sharp. The cheek teeth were cusped and the cusps were arranged in a single line. The nostrils were located in a for­ward position and not on the top of the skull as they are now. All are extinct.

Examples:

Protocetus, Eocetus, Basilo saurus (Zeuglodon).

Suborder (ii) Odontoceti:

It includes toothed whales. The members may be fresh­water and marine. The fresh-water forms retain many primitive characters. The cervical vertebrae in them are not fused. The interlock­ing processes of the thoracic vertebrae are more prominent. There are many double- headed ribs. They bear a fairly long beak with sharp homodont teeth on both the jaws. The eyes are rudimentary.

External nostrils are uni­ted to form a single hole. The nipples in the females lie close to the anus. The dorsal fin is represented by a ridge. The head is round and the skull bears a bony process called maxillary crest. Hyperphalangy and hyperdactyly are absent. Size is smaller in fresh-water forms.

The marine forms are usually larger in size. The head is large and swollen at the ante­rior to form a rostrum. The rostrum contains a valuable whale oil called spermaceti. The lower jaw is long, narrow and bears teeth.

The upper jaw bone is wide posteriorly and lies above the frontal bones. Teeth in the upper jaw are vestigial. The maxillae and nasals are unequal in size. Anterior ribs have capitulum and tubercufum. Sternum is divided into Sterne brae. All seven cervical vertebrae are fused together. Secretion of the intestine forms a stone-like ambergris.

Content:

The suborder includes four extant and two extinct families. The extant families are:

(i) Platanistidae (the fresh water dolphins of the Orient and South America; Ganges Dolphin, Platanista (Fig. 10.94A);

(ii) Physeteridae (the sperm whale, Physeter (Fig. 10.94B), all oceans,

(iii) Ziphiidae (bottle-nosed whale, Hyperoodon, Antarctic and North Atlantic, and

(iv) Delphinidae (porpoise, Phocaena (Fig. 10.94C), all oceans; common dolphin, Delphinus, all oceans; narwhal, Monodon (Fig. 10.94D), Arctic sea; bottle-nosed dol­phin, Tursiops (Fig. 10.94E), all oceans; Killer whale, Orcinus (Fig. 10.94F), all oceans).

The extinct families are (i) Agorophiidae and (ii) Squalodontidae.

Suborder (iii) Mysticeti. (Baleen whales):

The order includes those whales which are toothless in adult stage. Teeth are replaced by more than 300 triangular plates or baleen. The baleen is made up of horny structures and hangs from the roof of the mouth and its free end is fringed.

The baleen is arranged in two rows one on either side of the upper jaw. Blubber is thin. The tongue is mus­cular. The dorsal fin is small and situated far back. The skull is symmetrical and the nostrils are paired. The sternum is not divided into Sterne brae. Ribs are single-headed. Cervical vertebrae are usually fused.

Content:

The suborder includes three extant fami­lies.

These are:

(i) Balaenidae (right whales, Balaena (Fig. 10.95A), temperate and Arctic oceans; Pigmy right whale, Caperea, Atlantic); (ii) Eschrichtidae (grey whale, Eschrichtius, North Pacific); (iii) Balaenopteridae (rorquals, Balaenoptera (Fig. 10. 95B), all oceans; hump­back whale, Megaptera, all oceans).

Examples:

Blue whale, Balaenoptera musculus (Fig. 10.95B) (the largest animal in existence); Humpbacked whale, Megaptera novaeangliae; Common Rorqual or Finner whale, Balaenoptera physalus; Sei whale, Balaenoptera borealis; Piked or Lesser Rorqual, Balaenoptera acutorostrata; Right whale, Balaena mystecitus (Fig. 10.95A).

Cohort (d) Ferungulata:

A large number of mammals which are both herbivorous and carnivorous in habit are included in this cohort. The inclusion of carnivorous and hoofed mammals under one head may appear strange but palaeontological evidences show that both of them arose from a common mammalian stock during Pliocene period (Simpson, 1945).

The characteristic features of Ferungulata are:

i) They are either carnivorous or herbi­vorous.

ii) The locomotion is either plantigrade, digitigrade or unguligrade.

Superorder Ferae:

Order 1. Carnivora [L. Carno = flesh + voro, to eat], 284 species. Dogs, Fox, Tiger, Civet, Seals:

This order includes the strongest and most formidable of all the terrestrial mam­mals. They are endowed with proclivities of a violent nature and organised for slaughter and carnage. They form a well-diversified group and show a wide range of adaptive radiation.

1. Most carnivores are terrestrial but some forms are aquatic. Terrestrial forms have strongly built limbs. In aquatic forms, the distal part is modified into paddles and hind limbs are directed backward.

2. Number of digits in the limbs are usually five but never less than four. Digits end in sharp claws and claws may be retractile.

3. Locomotion is digitigrade or plantigrade.

4. Brain is highly developed. Intelligence in the form of mental alertness and coordi­nated actions is present.

5. Sense of smell is well-developed.

6. Dentition is highly specialised and cha­racteristic.

7. Intestine is short and caecum is small or absent.

8. Scrotal sac is present.

9. Mammae are abdominal in position.

10. Uterus is bicornute.

11. Placenta is deciduate and zonary.

12. The skull is short and high. Sagittal (longi­tudinal) and lambdoidal (transverse) crests are well-developed.

13. Zygomatic arch is strongly built.

14. The temporal fossa is deep.

15. Glenoid fossa is transverse.

16. The tympanic bulla is large and rounded.

17. The cavity of the bulla is separated into an anterior and a posterior part of the bulla which is often associated with a paroccipital process.

18. Three pairs of incisors are present both in the upper and lower jaws. Canines are sharp and pointed.

19. The last upper premolar and first lower molar have become transformed into chisel-shaped structures that act against each other like the blades of a pair of scis­sors. They are jointly known as carnassial teeth, absent in seals. Fig. 10.96 shows the carnassial teeth in different carnivores. The last two molars in each jaw act as crushing teeth.

20. The atlas is large and is provided with wing-like lateral processes.

21. The neural spine of the axis is long and compressed and the odontoid process is conical.

22. Cervical vertebrae are with small spine and long transverse processes.

23. Thoracolumbar vertebrae are 20 or 21. Anterior thoracics are with slender but backwardly directed spines. Posterior thoracics bear well-developed metapophyses and anapophyses.

24. Lumbar vertebrae have short spine and long transverse processes.

25. The sternum is long, narrow and made up of 8 or 9 sternibrae. Sternal ribs are not calcified. The clavicles are reduced.

26. In the wrist, scaphoid, lunar and centrale are fused.

This Order includes three suborders:

Creodontia, Fissipedia and Pinnipedia. The Order Creodontia includes the extinct forms.

Suborder (i) Creodontia:

The suborder includes extinct members which were very dominant flesh-eaters of Pliocene. The mem­bers were moderate in size. The limbs and the body were long and slender. The limbs were pentadactylous and digitigrade.

Brain was poorly developed and the skull arch was low. The dentition was complete. Carnassial teeth were still to appear. It is believed that from this centralised and un-specialised assembly diverse modern carnivores have evolved which lived until Oligocene.

Examples:

Tricentes, Claenodon, Arctocyon, Patriofelis.

Suborder (ii) Fissipedia:

Terrestrial mem­bers of the Order Carnivora are included in this suborder. On the basis of anatomical cha­racters such as structure of the auditory bulla, presence or absence of alisphenoid and the pattern of molar teeth, the suborder has been divided into two superfamilies’:

Superfamily:

Canoidea or Arctoidea.

The tympanic bulla is not partitioned or partition is incomplete. Paroccipital process is small or absent. Dentition in most forms is 3.1.4.2 / 3.1.4.3.

There are five families of which one is extinct.

Family:

Miacidae (Extinct).

Family Canidae:

Distribution is universal excepting Australia, New Zealand and Madagascar. The limbs are long. Forelimbs are with 4 or 5 digits. Hind limbs are always with 4 digits. Pollex and hallux are reduced. Claws are non-retractile and locomotion is digitigrade. Carnassials are well-developed. Last upper premolar is absent. Fig. 10.97 shows the organisation of skull and lower jaw of a typical carnivore, Canis.

Examples:

Wolf, Canis lupus (dry open plains of peninsular India and in the upper Himalayas); Jackal, Canis aureus; the Indian fox, Vulpes bengalensis (throughout the country); the red fox, Vulpes vulpes (Northwestern arid region and from Kashmir to Sikkim; Indian wild dog, Cuon alpinus (forests of India).

Family: Mustelidae:

Members are slender bodied, long-necked but short-legged forms. Claws are non-retractile. In semi-aquatic Otter, the digits are webbed. Carnassial teeth are well-developed. Last upper molar is expanded. Tympanic bulla is not inflated and internal septum is absent.

Examples:

Lutra (Otter), Meles (Badger), Mustella (Weasels).

Family: Ursidae:

Members are large. Body is covered with coarse hairs. Limbs are with five digits and digits are clawed. Locomotion is plantigrade. Tail is short. The tympanic bulla is flat. Carnassial teeth are not formed. Molars are large, elongated and much tuberculated. The last molar is reduced. Members undergo hibernation.

Example:

The sloth bear, Melursus ursinus (forests tracts of India); the Himalayan black bear, Selenarctos thibetanus (forested areas of Assam and Himalayas); the brown bear, Ursus arctos (Himalayas).

Family: Procyonidae:

Distribution is America, excepting Panda which is oriental. The claws are not retractile. The first premolar and last molar are absent. Carnassial teeth are absent, The upper molars are round in shape.

Examples:

Procyon (Racoon), Ailurus fulgens (the red Panda), Potos (Kinkajou, carnivore with a prehensile tail), Ailuropoda, melanoluca, giant panda of China (Fig. 10.98).

Superfamily: Feloidea:

The tympanic bulla is divided by a complete septum into anterior and posterior chambers. Paroccipital process remains in close contact with the bulla. Dentition is 3.1.3.1/3.1.2.1. Carnassial are well-developed. Premolars and molars are reduced in size. Locomotion is digitigrade. It is divided into three families.

Family: Viverridae:

The members are, found in Asia and Africa. Members possess short pinna and legs. Digits have non-retractile claws. The skull is large and dentition is typical. All civets possess scent glands which are situated in the perineal area. It is seen exter­nally as a large pouch-like structure with hairy lips. The secretion of the gland has odoriferus properties and the active substance is cive­tone.

Examples:

Civet (Viverra) (Fig. 10.99A), Mongoose (Herpestes) (Fig. 10.99B), Binturong (Arctictis) (Fig. 10.99C).

Family: Hyaenidae:

The members are found in Asia and Africa The anterior part of the body is massive and slants posteriorly. Body is stripped and the pinna is large. The number of digits in each limb is four. Digits end in. non-retractile claws. Carnassial teeth are well developed. There is one molar in each jaw and the upper molar is vestigial. The tympanic bulla is partially divided by a rudi­mentary internal septum.

Example:

Striped hyaena, Hyaena hyaena, (Fig. 10.100), (South-western Asia, northern Africa and India); Spotted hyaena, Crocuta crocuta (Africa).

Family: Felidae:

The members are dis­tributed widely though most members are found in the tropics. They are absent in Australia and Madagascar. The members are very active predators. Body is large. Eyes and Pinnae large tail is long.

The digits end in claws and the claws are retractile. Pads are present beneath the digits. Skull is very strongly built. Carnassial teeth are well-developed .Premolars are reduced in size and number. There are three premolars in the upper jaw (fig (10.102) and two on the lower jaw. Molars are reduced.

Examples:

Cat, Felis domesticus; Tiger, Panthera tigris (Fig. 10.101 A); Lion, Panthera leo (Fig. 10.101B); Leopard, Panthera pardus (Fig. 10.101C); Hunting leopard or Cheetah, Acinonyx jubatus (Fig. 10.101D); Jaguar, Felis onca; Puma, Felis cougar.

Suborder (iii) Pinnipedia:

Members belonging to this suborder are marine but they come up on land to give birth to youngs. The body is streamlined and is covered with soft hairs. In Seals, hair is present on palm and sole. Tail is short. Eyes are directed upwards. Nostrils are provided with valves.

Penis is pro­vided with a bone. Folds of skin cover the gen­italia and nipples. Limbs are modified to form paddles. Hind paddles are directed back­wards. Retia mirabilia are present. This subor­der differs widely from the suborder Fissipedia. The differences are tabulated in Table 52.

The suborder Pinnipedia includes the following 3 families: Otariidae, Odobenidae and Phocidae. Fig. 10.103 shows the skeleton of Seal, Phoca to give the skeletal organisation of Pinnipedia in general. In the first two fami­lies, the hind-foot is used in locomotion on land. The forelimbs are used in swimming.

In the third family the hind limbs are attached with a fold of skin along with the tail and the hind limbs are used in swimming. The pinna in Otariidae is provided with a cartilage and hence the name. In Walruses, the upper canines become large to form tusks in both the sexes.

Examples:

Phocidae — common seal, lion, Zalophus (Fig. 10.104B); Odobenidae — Phoca (Fig. 10.104A), Fur seals (Callorhinus). the Atlantic walrus, Odobenus (Fig. Otariidae — Sea-lions, Eumetopius; Cow sea 10.104C).

Distribution of Felidae in India:

The members of Felidae are called “beasts of prey” and highly specialised group among carnivores. They are recognised by rounded head, flattened muzzel, slim body, long legs with retractile claws and teeth. The teeth are highly adapted for biting, cutting and tearing the flesh of the prey.

The canines are large and strong, and are adapted for seizure and killing of prey. The carnassial teeth are large and well- developed. The sharp claws are used to strike, and hold struggling prey. The tiger, lion, leo­pard, the larger and smaller cats are included under the family Felidae and Order Carnivora. An account of Indian felidines with their distribution is given here.

1. The Tiger:

Scientific name:

Panthera tigris (Fig. 10.101 A (Linnaeus).

Races:

The tiger (Panthera tigris) has eight races or subspecies. These are:

(i) The Indian tiger (Panthera tigris tigris), the typical race,

(ii) Indochinese tiger (P. t. corbetti),

(iii) The Chinese tiger (P. t. amoyensis),

(iv) The Siberian tiger (P. t. altaica),

(v) The Caspian tiger (P. t. virgata),

(vi) The Sumatran tiger (P. t. sumatrae),

(vii) The Javan tiger (P. t. sondaica), and

(viii) The Bali tiger (P. t. balica).

Indian race:

Panthera tigris tigris (Linnaeus).

Distinguishing features:

The distinctive features of the animal are the vertical transverse black stripes against reddish yellow body, and the black markings are symmetrical above the eyes but asymme­trical on cheeks.

Distribution:

The Indian tiger ranges throughout peninsular India from the Himalayas to Kanyakumari (Cape Comorin) except in the deserts of Rajasthan, Punjab and Kutch. They are seen at an altitude of 3050 m (10000 ft.) of the Himalayas.

White tiger:

The white tiger is not a separate species or race. The white colour of the body is due to the mutation of the recessive gene. They are partially albino. The white tigers have whitish body with dark brown stripes and blue eyes.

They were recorded from different states in the past, but maximum lumbers were reported from the forests of Rewa of Madhya Pradesh. The tiger is the National animal of India. The Siberial tiger is the largest in size and the Sumatran tiger is the smallest.

Status:

At the turn of the 19th century the number was estimated about 40,000 but the number declined drastically which reached to 1827 in 1971 census. In 1961, Jim Corbett estimated that only two thousand tigers existed in India. E. P. Gee in 1964, placed the number at four thousand.

In 1981 census the tiger population increased and estimated about 3015. In 1989, the tiger population increased to 4334. In 1993 census indicated downslide figure stan­ding at 3750. In 1997 census, rough figures indicate to be around 3000.

After the launch of Project Tiger in 1973, the tiger population increased to 4334 in 1989, but the trend has reversed since 1993 census. The decreasing trend in the number of tigers is indicative of illegal trade in tiger parts for use in traditional Chinese medicine.

2. The Lion (Fig. 10.101 B):

Scientific name:

Panthera leo (Linnaeus).

Races:

According to Prof. C. Groves (1982), there are 4 races or subspecies of lion. These are (i) Asiatic or Gir lion (Panthera leo persica), (ii) Sub-Saharan African lion (P. I. numbica), (iii) Cape lion (P. I. melanochaita) which is extinct in the wild, and (iv) the Barbary lion (P. I. leo), which is also extinct in the wild.

Indian race:

Panthera leo persica (Meyer).

Distinguishing features:

The body colour of the Indian lion is yellow-brown. The abdomen possesses a fuller fringe of hairs. The tip of the tail bears a longer tassel of hair, the feature which is found only in the lion of the cat family, Felidae. The mane is light or dark, rarely quite black.

Distribution:

1. Present:

The Asiatic lion is only restricted to the Gir Forest in Kathiawar, Gujarat. They are no longer found in other parts of Asia.

2. Past:

In 18th century the distribution of Asiatic lion was in Asia that covered Iraq, Iran, Arabia and the Indian sub-continent. In India, the lions were abundant in Saharanpur, Moradabad, Rampur and North Rohilkhand in 1822. The last lion in Central India was shot in 1873 near Guna (M.P.). In 1830, a good numbers of lions were recorded along the banks of the Sabarmati river and around Mt. Abu.

3. The Leopard or Panther (Fig. 10.101C):

Scientific name:

Panthera pardus (Linnaeus).

Races:

Pocock described eleven races of panther as found in Asia. Out of eleven Asiatic races, three occur in India. These are (i) Panthera pardus fusca (Meyer), (ii) Panthera pards millardi Pocock and (ii) Panthera pardus sindica Pocock.

Distinguishing features:

The distinguishing features of the panther are sleek short-haired animal with a bright fulvous coat marked with close-set black spots.

Distribution:

The leopards are distributed almost all over the country in wooded forests. Leopards from Kashmir are regarded as distinct race. R. C. Morris drew the attention of a small dark race in the Nelliampatti Hills in Cochin.

Black Panther:

Black panther is not a separate species. Its black colour is due to the excessive formation of colouring pigment, called melanin.

4. The Snow Leopard or Ounce (Fig. 10.105A):

Scientific name:

Panthera uncia (Schreber).

Distinguishing features:

It has a pale grey coat with paler black ro­settes. The undersurface is white. The forehead is high, with short muzzle and vertical chin.

Distribution:

The snow leopard of India ranges along the Himalayas from Kashmir to Bhutan. They are found at an altitude of 3965 m (13000 ft.) of the Himalayas above sea-level.

5. The Clouded Leopard (Fig. 10.105B):

Scientific name:

Neofelis nebulosa (Griffith).

Indian race:

Nneofelis nebulosa macrosceloides (Hodgson).

Distinguishing features:

The colour of the body varies from grey to yellowish brown with dark, irregular rosettes, lined with black at edges. The undersurface is white or pale tawny in colour. The long tail is marked with ring-like black markings.

Distribution:

The clouded leopard is found in the forests of Assam in India. It is also found in Sikkim, Nepal and Bhutan.

6. The Marbled Cat:

Scientific name:

Felis marmorata Martin.

Indian race:

charltoni (Gray).

Distinguishing features:

The body is pale yellow-brown in colour with stripes on head, neck and back. The mar­bled pattern, small blotches are on the flanks and small spots on the tail and on the under­side of the limbs. The marbled cat resembles the clouded leopard in colour.

Distribution:

They are found in the forests of Assam. They are also found in Nepal and Sikkim.

7. The Golden Cat:

Scientific name:

Felis temmincki Vigors and Horsfield.

Indian race:

temmincki Vigors and Horsfield (typical race).

Distinguishing features:

The colour of the dorsal coat is golden, brown to dark brown. A pair horizontal black stripes are seen on the cheek. The undersur­face is white, marked with small black or brownish spots. It is the largest (120 cm long) among lesser cats.

Distribution:

They are found in the deep forests of Assam and also found in Sikkim.

8. The Leopard Cat:

Scientific name:

Felis bengalensis Kerr.

Indian race:

Bengalensis Kerr, horsfieldi (Gray), trevelyani (Pocock).

Distinguishing features:

The colour of the dorsal coat is yellowish marked with black or brownish spots. The undersurface is white.

Distribution:

They are found in the forest regions from the Himalayas to Kanyakumari and also in Kashmir.

9. The Rusty spotted Cat:

Scientific name:

Felis rubiginosa (Ceoffroy).

Indian race:

rubiginosa Geoffroy.

Distinguishing features:

The colour of the body is greyish with spots and brown bars. The undersurface is nearly white with black spots.

Distribution:

They are found in the grass land scrub, and jungle of Kashmir, and in South India.

10. The Fishing Cat (Fig. 10.106):

Scientific name:

Felis viverrina Bennett.

Distinguishing features:

The body colour is earthy-grey brown marked with spots arranged longitudinally. Dark lines are seen on the forehead and shoul­der. The undersurface is somewhat whitish in colour with dark spots.

Distribution:

They are found throughout the country in scrub or in the thick forests.

11. The Jungle Cat (Fig. 10.107):

Scientific name:

Felis chaus Guldenstadt.

Indian race:

affinis Grey, kutas Pearson, prateri Pocock, kelaarti Pocock.

Distinguishing features:

The colour of the body varies from sandy grey to yellowish grey. A few cross bars of black colour on the posterior part of the tail.

Distribution:

It is distributed throughout the country.

12. The Desert Cat:

Scientific name:

Feli libyca Forster.

Indian race:

ornata Gray.

Distinguishing features:

The colour of the body is pale yellowish with dark stripes on the outside of the limbs. Two horizontal stripes are on the cheek region.

Distribution:

It is found in the scrub jungles of the drier parts of Rajasthan, Gujarat, Maharashtra and M.P.

13. The Caracal:

Scientific name:

Felis caracal Schreber.

Indian race:

schmitzi Matschie.

Distinguishing features:

The colour of the coat is reddish grey above and buff or white below. The ear is tri­angular with tufted hairs. A dark spot is present on each side of the upper jaw.

Distribution:

They inhabit in the drier parts of Rajasthan, Uttar Pradesh, Punjab, and Central India.

14. The Lynx:

Scientific name:

Felis lynx Linnaeus.

Indian race:

Isabellina Blyth.

Distinguishing features:

The colour of the body varies from pale grey to is abelline. It has a short tail and long erect tufts of hair at the tip of ears.

Distribution:

It is found in Ladakh.

15. Pallas’s Cat:

Scientific name:

Felis manual Pallash.

Indian race:

manual Pallash, nigripecta Hodgson, ferruginea (Ognev).

Distinguishing features:

The colour of the back and body is iron grey. The cat is small in size with long tail and broad head.

Distribution:

They are found in Ladakh.

16. The Cheetah or Hunting Leopard (Fig. 10.101 D):

Scientific name:

Acinonyx jubatus (Schreber).

Indian race:

venaticus (Griffith).

Distribution:

Once occurred in the plains and the hilly regions of peninsular India, is already extinct in India. Table 53 shows the distinction of leopard and hunting leopard.

II. Super-order Protoungulata:

Order 2. Condylartha:

This order resembles the creodonts in some respects and at the same time foresha­dowed the hooves. They were omnivorous and non-predaceous animals. The tooth pattern was different from creodonts. Shortening of jaws or reduction of incisors never appeared.

The astragalus was of creodont-carnivore type and the interlocking of carpus with centrale was quite evident. The third toe showed a ten­dency to become larger and paraxonic. They persisted from Paleocene to Eocene period.

Examples:

Meniscotherium, Phenacodus.

Order 3. Tubulidentata [L. Tubulus = small tube + dens = tooth] 1 species; Aardvark:

The order is represented by a single genus and found only in Africa.

1. The body is strongly built.

2. Hairs on the body are few in number.

3. The colour of the body is dull-grey.

4. The head is elongated to form a tubular snout.

5. Pinna is long.

6. Limbs are strong. The forelimbs are with four digits which end in claws. The hind limbs are provided with five clawed digits.

7. Mouth is small. The tongue is long and protrusible.

8. Incisors and canines are absent.

9. The cheek teeth, are 4 or 5 in number. They lack enamel but a coating of cement is present. When viewed under micro­scope the dentine appears tubular and hence the name of the order.

They are ant-eaters and the phylogenetic relationship is problematical.

Example:

Orycteropus afer, aardvark of Africa (Fig. 10.108) sole representative of the order.

Order 4. Notoungulata:

Fossil forms of this order have been dis­covered from Mongolia, North America and South America. It is believed that they were Asiatic in origin and migration to North America took place during Tertiary age through Berring Strait. The members were primitive, small and hoofed.

The skull and the jaws were heavily built. The postorbital process was not present. Zygomatic arch was very strong. The dentition was of uniform pattern from anterior to posterior. Canines have lost their typical shape. Molars were of lophodont type.

Examples:

Palaeostylops, Arcostylops.

Order 5. Litopterna:

The order includes a number of individu­als, some of which were half-made horses and the others were half-made camels. They evolved in South America in Paleocene period and continued through Pleistocene epoch to become extinct.

The skull was elongated and low and the nasal openings were situated far back on the upper surface of the skull. A post- orbital bar kept the eyes separated from the temporal region. The incisors were chisel- shaped. The cheek teeth were selenodont type.

Premolars tended to become molari form. The vertebral column was straight. The limbs were slender. The hind feet had three digits of those the middle was large and hoofed. The lateral toes were reduced.

Examples:

Diadiaphorus, Thoatherium.

Order 6. Astrapotheria:

This was an order which persisted in South America from Eocene to Miocene period. A trend to gigantism was exhibited by the members. The skull and jaws had peculiar modifications.

The front of the skull was short. The nasal bones were small and retracted in position suggesting the presence of a pro­boscis. Upper incisor was absent. The upper canines were greatly enlarged and they were like downwardly directed daggers.

The lower jaw was elongated. Lower incisors were present. The lower canines were large. It is believed that a long and tough upper lip was present between the retracted front portion of the skull and the front of the lower jaw.

Example:

Astrapotherium.

Superorder Paenungulata:

Order 7. Hyracoidea [Gk. hyrax = shrew + eides = form] 1 species. Hyraxes:

In Hyracoidea there is a peculiar admix­ture of primitive and specialised characters and they resemble different orders of mam­mals. They are found in Africa, Arabia and Syria.

1. They are small and rabbit-like in size.

2. Snout is splitted in some forms.

3. Pinna is short.

4. Tail is short.

5. Locomotion is plantigrade.

6. There are four digits in the forelimb and the fifth one remains as a vestige.

7. Hind limbs are provided with three digits. The digits end in hoofs except the second digit of the foot which is clawed.

8. The stomach is constricted in the middle.

9. Gall-bladder is absent.

10. The caecum has a pair of caecal pouches.

11. Testes are abdominal in position.

12. A single pair of pectoral mammae is pre­sent.

13. Uterus is paired.

14. The skull is with peculiar features. The postorbital bar arises from the parietal. This bar is complete in some forms. The jugal is stout and extends backward to take part in the formation of glenoid cavity. The periotic and tympanic bones are united together and not with the squa­mosal.

15. The tympanic forms a bulla and has a spout-like external auditory meatus.

16. The seventh cervical vertebra may be pierced by the vertebral artery. Thoraco­lumbar vertebrae are 22 in number.

17. Scapula is triangular and without an acromian.

18. The clavicle is absent.

19. The radius and ulna are crossed. Centrale persists in the carpus.

20. Astragalus is different from all other mam­mals.

21. A single pair of large and curved upper incisors with persistent root is present. Canines are absent.

22. The lower jaw bears two pairs of incisors which are comb-like.

23. There are 4 premolars and 3 molars. They are lophodont and all are alike.

Content:

The order includes a single family the Procaviidae (= Hyracidae).

Examples:

Hyrax (= Procavia) (coney), Dendrohyrax.

Order 8. Embrithopoda (= heavy feet):

The order is represented by a single genus which appeared in Oligocene in Egypt. Nothing is known about its ancestors or descendants. They were large as rhinoceros. Limbs were elephant-like. Feet were broad and spreading. A pair of massive and bony horns was present.

The base of the horn was extended between the nostril and cranium. The skeleton was heavy. The skull was large and the teeth formed a con­tinuous series from incisors to last premolars. The cheek teeth were long crowned.

Example:

Arsinotherium.

Order 9. Proboscidea [L. Proboskis = trunk] 2 species. Elephants:

The members belonging to this order are represented by an isolated group. At an early stage in their phylogeny they acquired a num­ber of peculiar and adaptive characters which distinguished them from other mammals. They are stamped with primitive and specialised characters.

1. The body is huge.

2. Skin is thick (pachyderm) and hairs are scanty.

3. The fusion and elongation of the nose and upper lip have resulted in the formation of a large prehensile trunk (Fig. 10.109A, B). Elephant trunks are so sensitive that they can pick up needles.

4. The nostrils are situated at the tip of the trunk.

5. The eyes are small and the pinna is large.

6. The tail is flat.

7. The limbs are pillar-like and pentadactylous. The digits are short, stout and united by skin. Each digit is provided with a small hoof and the back of the digits is suppor­ted by a pad of tissue.

8. Locomotion is of digitigrade type.

9. The cerebral hemispheres are convoluted but do not cover the cerebellum.

10. The precavals are paired.

11. The stomach is simple.

12. The intestine is long and caecum is large.

13. Testis is abdominal in position.

14. A pair of pectoral mammae are present.

15. Only one young is born at a time after a gestation period of 22 months.

16. Head gland is located in the temporal region of the males.

17. The skull is massive. Sutures of the skull are obliterated.

18. The facial and nasal parts are reduced. Frontal and parietals are separated.

19. Skull bones are with diploe or air-spaces (Fig. 10.109C).

20. Dentition is highly characteristic. There is a single pair of incisors in the upper jaw. Incisors are absent in the lower jaw. The upper incisors have no root and they grow to form tusk. The tusks are made of ivory which is a specialised dentine. The ivory is a hard creamy-white substance composing most of the part of tusks. Enamel remains as a small cap on the tusk for a short time and then wears off.

21. Premolars and canines are absent. In the adults, three molars are present in each half of the upper and lower jaws. The molars consist of a number of deep plates of enamel covered dentine bound toge­ther by cement (Fig. 10.109 D, E). Not more than two molars remain functional at a time. In case of wearing off, the third dormant molar comes up and replaces the worn out teeth.

22. The cervical region is short.

23. Thoracic vertebrae are with high neural spine.

24. Ribs are 20 in number.

25. Clavicle is absent.

26. Radius and ulna are crossed.

27. Carpus is larger than radius and is articu­lated with ulna.

28. The pelvis has broad ilia and vertical in direction.

29. Tibia and fibula are distinct.

30. The carpals and tarsals are serial and com­pressed.

31. The African elephant is the largest terres­trial animal on the earth.

Content:

It includes a single extant family Elephantidae with the genera Elephas and Loxodonta.

Examples:

Elephas maximus (Indian elephant) (Fig. 10.109A), Loxodonta africana (African elephant) (Fig. 10.109B).

Order 10. Pantodonta:

The order is represented by few forms which evolved during Paleocene and became extinct in Oligocene. The members were sheep-like in size during the early phase of their evolution. In the later phase there was an increase in size. The skull was long but low. The canines were large and the upper molars were triangular in shape. The limbs were heavy and short. The hind-limb had five digits, each terminated into a hoof.

Example:

Pantolambda.

Order 11. Dinocerata (= Terrible horns):

Fossil forms of the members of this order have been discovered from North America and Asia. They were evolved in Paleocene and became extinct in Oligocene. The body was large and heavy. The upper limb elements were long while the lower limb elements were short. The feet were broad and spreading. The skull was low. The front of the lower jaw was deeply flanged. The canines were long.

Example:

Prodinoceras.

Order 12. Pyrotheria (= Fire beasts):

A small and isolated group of South American ungulates is included in this order. They evolved during Pliocene and became extinct in Oligocene. They were gigantic in size and had many proboscidian features. The skull was large and the nasals were retracted indicating the presence of a trunk there. The zygomatic arch was strong and heavy.

The back portion or ascending ramus of the lower jaw was large. Two of the upper incisors on each side were enlarged to form the tusks. In the lower jaw, there was a single tusk-like incisor. Canines were absent on either side.

The cheek teeth were low crowned. Because of their similarities with Proboscidea they are considered to be proboscidean relatives. Modern opinion regards them as independent order of mammals.

Example:

Pyrotherium.

Order 13. Sirenia [Gk. siren, sea nymph] 4 species:

Evolution:

The members belonging to this order are probably early offshoot from the line of pro­boscidian evolution. Because of their aquatic adaptation they possess in their bodies many features that are similar to that of Cetaceans. But these similarities are due mainly to con­vergent evolution.

Distribution:

Members belonging to this order are either freshwater or marine and are found along the coasts of America, Africa, Indian Ocean, South Pacific and Australia. They are large herbivo­rous animals but they do not go to the open sea.

1. The body is large and streamlined.

2. Muzzle is round and the upper lip is pro­truding.

3. The neck is short.

4. Nostrils are located on the upper surface of head and are provided with valves.

5. Pinna is absent.

6. Eyes are small with muscular eyelids.

7. Hind limbs are absent.

8. Forelimbs are modified into paddles.

9. There are 5 digits in the forelimbs and the digits are webbed and nail-less.

10. Tail is round or rhomboidal in outline.

11. Hairs on the body are almost absent.

12. A thick layer of fat, called blubber, is pre­sent beneath skin.

13. The intestine is long,

14. Diaphragm is oblique in position and highly muscular.

15. Lungs are elongated and air-sacs are asso­ciated with them.

16. Retia mirabilia are present in the brain and elsewhere.

17. Testes are abdominal.

18. The mammae are pectoral in position and lie in skin pockets.

19. Brain is small and ventricles are excep­tionally large.

Fig. 10.110 shows the skeleton of a typical form, ‘Sea-cow’ of the order.

20. The skull bones are hard and compact.

21. The cranial cavity is long and narrow.

22. The supra-occipital extends forward but does not separate the parietals.

23. Broad supraorbital plates develop from the frontals.

24. The zygomatic arch is strong. The nasal bones are vestigial.

25. Tympanic and periotic bones can be eas­ily separated from other bones. Tympanic bone is ring-shaped. The external audi­tory meatus is reduced to a channel as in whales.

26. Premaxilla is large in dugongs. The ascending ramus of the mandible is well- developed.

27. Coronoid process is also well-developed.

28. The bones are characteristic for the solid structure with little or no marrow, the condition termed pachystosis.

29. The cervical vertebrae are not ankylosed.

30. Number of cervical vertebrae in manatee (Manatus) is only 6 and the neural arches are sometimes incomplete.

31. The trunk and thoracic vertebrae are more than the usual number with well- developed zygapophyses.

32. Facets in them are well-developed for articulation with rib heads.

33. Caudal vertebrae are numerous, flattened and are with wide transverse processes.

34. Sternum is not divided into sternibrae.

35. Ribs are many but are not connected with the sternum.

36. Sacrum is absent.

37. Dentition is characteristic. In Manatus there are up to twenty cheek teeth in each half of the jaws. They are covered with enamel and are lophodont. All are not used at a time and they are always in the process of replacement from the hind end.

38. In dugong the teeth are reduced. The cheek teeth are never more than six and are degenerated.

39. The scapula is narrow and curved back­wards.

40. Scapular spine is located in the middle.

41. Acromion is directed downwards.

42. Coracoid is conical in shape and well developed.

43. Clavicle is absent.

44. The radius and ulna are fused at their extremities.

45. Carpus is composed of seven bones in Manatee.

46. The pisiform bone is absent.

47. In dugong, carpals are fused. The five digits possess usual number of phalanges.

48. Hyperdactyly and hyperphalangy is absent.

49. The pelvis is vestigial and is without any connection with spinal column.

50. “The vertical position and rod-like shape suggest that it represents the ilia.

Content:

The order includes two extant families. The families are (i) Trichechidae (manatees, Trichechus = Manatus) and (ii) Dugongidae (dugongs or sea-cows, Dugong = Halicore).

Examples:

Halicore = Dugong (Fig. 10.111 A); manatee, Manatus = Trichechus (Fig. 10.111 B); Steller’s sea cow, Rhytina = Hydrodamalis. Steller’s sea cow of the North Pacific became extinct by the year 1768 by hunters.

Dugong or sea cow is found in the Red Sea and the shores of the Indian Ocean from East Africa to Australia, and Taiwan in the Pacific. It has a single species-Dugong dugon.

It has been reported from the coast of Digha, West Bengal, Bay of Bengal (Bharati Goswami, 1992), in the Gulf of Kutch, on the Coast of Malabar, around the Andaman Islands, in the Gulf of Manner and in the Mergui Archipelago (Myanmar). Manatee has three species and are found on the tropical Atlantic coasts and in the rivers of America and Africa.

Superorder Mesaxonia:

Order 14. Perissodactyla [Gk. Perissos = odd + daktylos = finger] 17 species. Horses, Zebras, Assess, Tapirs and Rhinos:

The present-day horses, asses, zebras, tapirs and rhinoceroses are included in this order. The evolutionary trends of this order from Eocene to recent age are very well-known.

1. The perissodactyls are large, herbivorous odd-toed mammals having a streamlined body.

2. The neck and facial parts are elongated.

3. The tail with long tuft of hairs is present.

4. The limbs are elongated raising the body above the ground.

5. Of the five digits, the 1st and 5th digits are lost. The 2nd and 4th digits remain as splints. The middle or third digit is stout and is provided with hoof. The axis of the limb passes down the third digit. This type of foot is known as mesaxonic foot. Except tapirs, the number of toes in each foot .is usually odd, either one or three.

6. Horns are absent in most forms.

7. The stomach is undivided and simple.

8. Intestine is long.

9. Caecum is large and sacculated.

10. Gall-bladder is absent.

11. The brain is highly complicated.

12. Testes are usually abdominal.

13. Mammae are inguinal and with teats.

14. The skull is elongated.

15. Supraoccipital bears a transverse crest.

16. A sagittal crest runs along the sagittal suture.

17. The par-occipital process is directed downwards and emerges from the exoccipital.

18. The nasals are large.

19. The orbit is surrounded by bones.

20. The front portion of the skull and lower jaws are deep to accommodate the cheek teeth.

21. The incisors are three in each quadrant of the jaws.

22. Canine is present in males. Its absence in females results in the formation of a diastema.

23. In adults molars and premolars are three in each half of the jaws.

24. The cheek teeth are lophodont in nature. The premolars tend to be molarified.

25. In the cheek teeth, ridges of enamel transverse to the long axis of the jaw, are present to form an efficient grinding sur­face.

26. The first vertebra is provided with a peg ­like odontoid process.

27. The dorso lumbar vertebrae are 22 or 23.

28. The number of ribs are increased.

29. The ilium is vertical.

30. The upper part of both the limbs are reduced. The lower parts of the limbs are elongated. This has resulted in a condition in which the elbow and the knee lie close to the body and the ankle and wrist are high up.

31. The ulna is reduced.

32. The magnum or distal carpal of the wrist is enlarged and united with the proximal carpals. The third metacarpal is the longest. The 2nd and 4th metacarpals are vestigial.

33. The femur is provided with a prominent process on the other surface of the shaft. The process is called third trochanter.

34. The fibula is reduced.

35. The astragalus has a double-keeled pulley- shaped surface for articulation with tibia. The distal surface of the astragalus is flat.

36. The third metatarsal of the hind limb is long and erect and is known as cannon bone.

37. The 2nd and 3rd metatarsals are vestigial and remain as splint bones.

It includes two suborders:

Suborder (i) Hippomorpha:

The suborder Hippomorpha includes extinct Paleotheres, Titonotheres, Chalicotheres and the horses. The first three evolved during early Eocene, attained the peak of their evolutionary deve­lopment in middle Oligocene and then died out. They had a short but dramatic phylogenetic history. The horses, on the other hand, survived through the ages.

Family Equidae:

The horses, asses and zebras are included in this family. They have single-digested limbs. The middle is the func­tional digit. The 2nd and 3rd digits are pre­sent as splints. Other digits are absent. The premolars in them tend to be molarified. Radius and ulna are fused.

Examples:

Equus cabalus (Horse), Equus (= Asinus) hemionus (Fig. 10.112) (Indian wild ass). There are 4 striped species of African Zebra. They are Equus quagga, E. burchelli, E. gravyi and E. zebra.

E. przewalskii (Only wild horse is found in Central Asia).

Suborder (ii) Ceratomorpha:

The subor­der includes tapir and rhinoceros. They arose in Eocene and are surviving today. But the rhinoceros are on the verge of extinction.

Family Tapiridae:

The members of the family are less specialised. Their distribution is discontinuous as they are found in Central and South America, Malaya and Indonesia.

The tapirs have a short proboscis formed by the nose and upper lip:

The digits are stout. There are four digits in the forelimb and three digits in the hind limb. The digits bear hoof. The middle digit is large and the axis runs through it. The post-orbital bar in the skull is absent. The nasal bones are small and pointed upwards. The number of teeth is 42. The teeth are persistently brachyodont and without cement. Molar teeth are lophodont and with­out extra cusps.

Example:

Tapir, Tapirus(Fig. 10.113).

Family Rhinocerotidae:

Members belong­ing to this family are massive in construction and are represented by the Rhinoceros of India and Africa and S. E. Asia. The skin is very thick and folded, called Pachyderm. Hairs are scanty. The horn on the nasal bone is very characteristic.

The horn is made up of keratinized fibres cemented together. There is a single horn in Indian rhi­nos. In African rhinos, there are two horns, one anterior and one posterior along the same line on the nasal region. The limbs are massive and each ends in three digits. The digits are provi­ded with hoofs. The axis of the body passes along the middle digit. The pinna is well-developed. The upper lip is long and prehensile.

Rhinoceros use infrasonic waves of about 5 Hz to signal each other. The skull is massive and strongly built. Canines are absent. The neural spines of the thoracic vertebrae are long. More than usual number of ribs is present. The ilia are broad and vertically placed.

Examples:

Rhinoceros unicorns (Indian rhino, Fig. 10.114), Diceros bicornis (African two-horned rhinos), Ceratotheriun simum (African two-horned, white, or square-lipped rhinoceros).

Dicerorhinus sumatrensis (two-horned Sumatran rhinos) live in dense forest of Sumatra, Malaysia and Borneo. They are much smaller than the four other rhino species.

They have two horns and a lot of hair on the body. It is one of the most threatened animals and is about over 500 in their habitats. Rhinoceros sondaicus (Javan rhino) which was about 50-54 in population in 1984 census and is now found in Ujung Kulon in western Java.

Superorder Paraxonia:

Order 15. Artiodactyla [Gr. artios = even + daktylos = finger] 213 species. Pigs, Hippos, Camels, Deer, Sheep, Goat, Cattle, Yak, Buffaloes:

The members of this order are more varied than Perissodactyla.

1. They are large herbivorous mammals.

2. The neck is elongated.

3. The tail is small.

4. Members usually possess a pair of epider­mal horns. Horns may be hollow or solid and are located on the frontal bone.

5. The limbs are elongated.

6. The number of digits is 2 or 4 in each limb.

7. The third and fourth digits are larger and bear hoof. The axis of the body passes between the middle of the 3rd and 4th digits (Paraxonic foot).

8. The eyes are large with horizontal pupil.

9. The pinna is large.

10. The tongue is long, mobile and prehen­sile.

11. Stomach is complicated and is divided into several chambers.

12. Intestine is short.

13. A short caecum is present.

14. Call-bladder is present.

15. Mammae are abdominal or inguinal in position and may be more than one pair.

16. Scent glands are often present.

17. The facial part of the skull is elongated.

18. Odontoid process of the axis is spout-like.

19. Thoracolumbar vertebrae are of constant number of 19 and are with long neural spines.

20. The clavicle is absent.

21. Ischium of the pelvic girdle is well- developed.

22. Femur has two trochanters.

23. Radius and ulna as also the tibia and fibu­la are fused.

24. Astragalus is provided with two facets of equal size for articulation with the tarsals. Calcaneum articulates with the fibula. Both ends of calcaneum are pulley-like.

25. Upper incisors are absent and the space left by them is hard.

26. Premolars are simple in construction than molars.

27. Molars are hypsodont.

28. The cheek teeth bear longitudinal ridges of enamel.

Hippopotamus, giraffe and okapi use infrasound to communicate each other.

The order is divided into 3-suborders.

Suborder (i) Suiformes:

Some mammal-logists consider the members of this suborder as the primitive of all artiodactyls but others consider them to be distinct to occupy the status of a suborder. Members belonging to this suborder have a heavy built body. Limbs are short. Number of digits is four and each one is hoofed. Both metacarpals and metatarsals are free. Some of the members retain the normal quota of 44 teeth. Canines appear triangular in section. Molars are bunodont with secondary cusps. Upper molars retain primitive tritubercular condition.

Content:

This suborder is represented by 3 extant families.

The families are:

(i) Suidae (e.g., Pig, Sus, worldwide; Wart-hog, Phacochoerus, Africa);

(ii) Tayassuidae (e.g., Peccary, Tayassu, Central and South America); and

(iii) Hippopotamidae (e.g., Hippopotamus, Hippopotamus amphibius, the second largest terrestrial vertebrates, found in Africa).

Examples:

Indian wild boar, Sus scrofa (Fig. 10.115).

Pig:

Sus whose body is stumpy and colour is dark-grey with fewer number of hairs. Hairs are hard and bristle-like. A row of hard bristles is present on the neck and along the mid-dorsal line.

Snout is elongated and nostrils are terminal. Limbs bear four digits, of which the 3rd and 4th reach the ground. Digits are provided with hoofs. Original dental formula is retained. Dental formula is 3.1.4.3/3.1.4.3. Canines of both jaws form tusks specially in males. They are gregarious animals and prefer marshy places.

Hippopotamus:

Hippopotamus amphibius is an amphibius mammal, found in Africa. Body is massive and measures 4-25 metres in length. Muzzle is broad. Nostrils, eyes and pinnae are shifted more towards the dorsal side of the head. The tail is short. The skin is thick with few hairs. Each limb bears 4- hoofed digits. They are herbivorous. Red sweat is a peculiarity in these animals.

Suborder (ii) Tylopoda:

Members of this suborder evolved from a distinct stock during Eocene period in North America. The limbs are long. Only the third and fourth digits are present at the end of the limbs. Hoof is absent. Nails are present at the end of the digits. Terminally, the digits are provided with cushion-like pad. Lips and tongue are tough. Stomach is three-chambered. Red blood cells are oval in outline.

The dentition in young and adult stages diggers. In young, three pairs of incisors in the upper jaw are present. But in adults only the 3rd pair are present. The space left by the first two pairs becomes very hard. The lower jaw bears three pairs of incisors. Incisors are canine-like.

Canines are present:

Premolars are reduced and their number is two in each quadrant. Molars are with 4 cusps and they are selenodont and hypsodont. In the limbs metacarpals and metatarsals are fused forming cannon bones. Lateral digits are totally lost. In the ankle navic­ular and cuboid remain separate.

Examples:

Bactrian or two-humped camel of Gobi desert in Central Asia, Camelus bactri­anus (Fig. 10.116A); the one-humped Arabian Camel, Camelus dromedarius. Guanaco, Lama guanicoe (Fig. 10.116B); Alpaca, Lama pacos; Llama, Lama peruana; Vicuna, Vicugna vicugna — all are found in South America.

Suborder (iii) Ruminantia:

This diverse group is most successful amongst the artiodactyls. Body is large. Tongue is prehensile. Limbs are with two functional digits. The 2nd and 5th digits may remain as vestiges in some. Horns of several types are present on the frontal bones. Horns may be present in one or in both sexes. Stomach is of ruminant type and is made up of four chambers.

Incisors and at times the canines are absent in the upper jaw. Incisors and canines of the lower jaw are spatula-shaped. Premolars are reduced. Molars are hypsodont and selenodont. Cannon bones are present. Fibula is reduced to a nodule-like form. Navicular and cuboid are fused together.

Content:

This suborder includes 5 extant families.

They are:

(i) Tragulidae:

They are small, about 30 cm high. The upper canines have developed into tusks. They have no horns, e.g., Mouse deer (Tragulus), India and S. E. Asia; water chevrotain (Hyemoschus), Africa.

(ii) Palaeomerycidae:

The males have large upper canines that have developed into tusks. It has no horns and face glands. It has a gall bladder. The musk gland is situated beneath the skin of the abdomen in the males. The gland acquires the scent of musk when it is dried. Palaeomerycidae is represented by only Musk deer (Muschus) and found in central and north east­ern Asia. The musk deer occupies a place in between deer and antelope.

The active substance derived from the musk deer is called muscone.

(iii) Cervidae:

The upper incisors are absent. The males carry solid branched antlers. The antlers are also present in the females of reindeer. They are shed and regrow annually; e.g., Kashmir stag (Fig. 10.117), Swamp deer, brow-antlered deer, sambar, red deer (Cervus) — Holarctic; Reindeer (Rangifer); Holarctic; European elk or moose (Alces), Holarctic; Roe deer (Capreolus), most of the Europe, north Asia; Fallow deer (Dama dama); Europe.

(iv) Giraffidae:

The animal bears a long neck with elon­gated cervical vertebrae. The head bears skin covered bony prongs in both sexes. The legs are long and lateral diits are absent in giraffes. They are browsers, e.g., Giraffe (Giraffa) and Okapi (Okapia) — tropical Africa.

Giraffe:

Giraffa camelopardalis or Giraffe is found in Tropical Africa. The body is large. The forelimbs are longer than the hind limbs. The neck is very much elongated though the number of cervical vertebrae remains con­stant (Fig. 10.118).

The colour of the body is bright yellow with brownish spots at intervals. The tongue is prehensile. The maximum weight of the body is carried by the fore limbs and the hind limbs are used for propulsion. Both sexes bear small horns which remain permanently covered by velvet.

(v) Antelocapridae:

The family includes only mammal, pronghorn antelope, Antilocapra of North America. They possess horns, called prong horns and molars have high crowns.

(vi) Bovidae:

Ruminants are without incisors and canines. They are with permanent and usually un-branched horns containing a bony core. The horns are smaller or absent in females.

Examples:

Cattles, Yak (Bos) — worldwide; Coat (Capra), worldwide; Sheep (Ovis), worldwide; American Bison (Bison bison, Fig. 10.119D), Holarctic; wild buffalo (Bubalus), India; Blue sheep (Pseudosis), Tibet, Nepal, Sikkim, Kumayon Himalayas of India; Black buck, Antilope cervicapra; Elands, Taurotragus; Gazelles, Gazella-Africa, Eurasia; Impala, Aepyceros-Africa; Blue bull, Boselaphus- India.

Cheetal (Axis); Indian bison or Gaur (Bos gaurus, Fig. 10.119A); Yak (Bos grunniens, 10.119B); Wild buffalo (Bubalus bubalis, Fig. 10.119C); Sheep (Ovis, Fig. 10.119E); Black buck (Antilope cervicapra), Fig. 10.119F).

Indian Mammals:

About 4445 extant mammals (Pough et al., 1996) have been recorded from the diffe­rent parts of the world of which 500 species are known from the Indian region (Prater, 1980). Simpson’s (1945) classification on mammals recognised 18 living orders, of which 12 are represented from the Indian region. A brief list of Indian mammals with their distribution is given here.

Order 1:

Insectivora Comprises 4 fami­lies:

(i) Tupaiidae (Tree shrews),

(ii) Erinaceidae (Hedgehogs),

(iii) Talpidae (Moles) and

(iv) Soricidae (Shrews).

The Tupaiidae include 3 species:

(i) The Malay tree shrew, Tupaia glis (eastern India),

(ii) T. nicobarica (Nicobar Islands) and

(iii) Indian tree shrew, Anathana ellioti (Peninsular India, south of the Ganges).

The Erinaceidae com­prise two Indian hedgehogs, one of them is Pale hedgehog, Paraechinus micropus (Punjab to Tamil Nadu) and other is Long- eared hedgehog, Hemiechinus auritus (Desert area of Kutch and Punjab).

Talpidae include the short tailed mole, Talpa micrura micrura (Central and eastern Himalayas), and white-tailed mole, T. m. leucura (Khasi and Naga hills of Assam). Soricidae include different genera, such as Suncus, Crocidura, Anurosorex, Nectogale, Soriculus, Chimmarogale and Sorex, of which grey musk shrew, Suncus murinus, occurs throughout India.

Order 2:

Chiroptera is divided into 2 major groups.

They are:

(i) Megachiroptera which possesses all the frugivorous bats and

(ii) Microchiroptera that includes insectivo­rous or carnivorous bats. Among the diffe­rent species of Megachiroptera, Flying fox, Pteropus giganteus; Fulvous fruit bat; Rousettus leschenaulti, short nosed fruit bat Cynopterus sphinx are common throughout India. The microchiropteran species are great eastern horshoe bat; Rhinolophus luctus, Indian pipestrelle; pipistrellus coromandra, common yellow bat; Scotophilus heathi; painted bat, Kerivoula picta and Indian false vampire, Megaderma lyra com­mon throughout India.

Order 3:

Primates includes 3 families— Cercopithecidae, Lorisidae and Hylobatidae. Cercopithecidae include 2 genera— Presbytis and Macaca. Presbytes contains about 5 species and Macaca about 7 species. Presbytes are recognised by tall, slim body, long tail and absence of cheek pouch and Macaca has sturdy, squat body, short tail and cheek pouches. The Common Langur, Presbytes entellus (Throughout India except western deserts), the capped Langur, P. pileatus (Assam), the Golden Langur, P. gee/ (Assam, between the rivers Sankosh in the west and Manas in the east), the Nilgiri Langur, P johni (Southern India), Phyre’s Leaf Monkey, P. phayrei (Tripura), and the Rhesus Macaque, Macaca mulatta (Assam, Northern and Central India as far south to the Godavari river), the Bonnet Macaque, M. radiata (Peninsular India as for north as Bombay on the west and the Godavari river on the east), the Assamese Macaque, M. assamensis (From Mussoorie to the hill ranges of Assam and Sundarbans), the Stumptailed Macaque, M. speciosa (Assam), the Pigtailed Macaque, M. nemestrina (Naga Hills), the Lion-tailed Macaque, M. silenus (Western Ghats), Crab eating Macaque, M. fascicularis (Nicobar Islands) are included under cercopithecidae. Lorisidae include the Slender Loris, Loris tardigradus (South India) and the slow Loris, Nycticebus coucang (Assam and Nagaland). Pongidae contain only one species – the Hoolock, Hylobates hoolock (Assam). Of the above-mentioned species of primates, the golden langur is known by E. P. Gee in (1955).

Order 4:

Pholidota include the Indian Pangolin, Manis crassicaudata (Throughout India) and the Chinese Pangolin M. pentadactyla (North-eastern India). They belong to the family Manidae.

Order 5:

Rodentia include rats, mice, squirrels and porcupines or the group which include the gnawing animals. The house mice, Mus musculus; Indian field mice, M. booduga; Indian mole rat, Bandicoota bengalensis; Bandicoot rat, Cannomys badius. Indian porcupine, Hystrix indica are more or less common throughout India.

The giant squirrel (Ratufa indica (deciduous evergreen forests of peninsular India, south of the Ganges), common giant flying squirrel (Petaurista petaurista) (larger forests of peninsula, south of the Ganges), the Malayan giant squirrel (Ratufa bicolor) (Assam, Sikkim and Bhutan); the five striped palm squirrel (Funambulus pennanti) (Indian peninsula), the three striped palm squirrel (F. palmarum) (Indian peninsula) are included under the order Rodentia.

Order 6:

Lagomorpha comprise two families, the Leporidae (hares and rabbits) and the Ochotonidae (mouse hares). The Indian hare (Lepus nigricollis) (throughout India), the Himalayan mouse hare (Ochotona roylei) (the Himalayas from Kashmir to Moupin), and the hispid hare (Caprolagus hispidus) (U.P. to Assam) are included under Lagomorpha. The true rab­bits are not found in India but the closely related Assam rabbit or hispid hare is found in the foothills from U.P. to Assam.

Order 7:

Cetacea is represented by whales and dolphins in Indian waters. They are Gangetic dolphin, Platanista gangetica (Ganges, Brahmaputra and Indus rivers), the common dolphin, Delphinus delphis (coastal water of Andhra Pradesh, Tamil Nadu, Gujarat and W. Bengal), the blue whale, Balaenoptera musculus (Bay of Bengal, Arabian sea) and the sperm whale, Physeter catodon (Bay of Bengal).

In the last part of 19th century the Indian pilot whole, Gobiocephalus indicus report­ed from the brackish water of the Salt Lake areas in Calcutta.

The Indus dolphin is now considered as a separate species, Platanista minor (= indi) due to its small size and separate habitat. The Ganges dolphin are called susuk or sishuk in the Bengali, hiho or siho in Assam, huhh in Cachar and Sylhet.

Order 8 Carnivora include 7 families:

(i) Canidae

(ii) Ursidae

(iii) Procyonidae

(iv) Mustelidae

(v) Viverridae

(vi) Hyaenidae and

(vii) Felidae.

The well-known species under the family canidae are the Jackal, Canis aureus (throughout India); the Indian Fox, Vulpes bengalensis (throughout India except north-western border); the Wolf, Canis lupus (dry open plains of Peninsular India); the Red Fox, Vulpes vulpes (Ladakh, Kashmir and the Himalayas) and the Indian Wild Dog, Cuon alpinus (Peninsular India), etc.

Ursidae include the Sloth Bear, Melursus ursinus (Forested tracts of India); the Brown Bear, Ursus arctos (North western and Central Himalayas) and the Himalayan Black Bear, Selenarctos thibetanus (Kashmir, Assam and the Himalayas). Procyonidae is represented by a single species, the Red Panda, Ailurus fulgens (Darjeeling and Sikkim).

Mustelidae contains Weasels, Martens, Badgers, Ratels and others. Some common species are, the common otter Lutra lutra (Kashmir, the Himalayas, Assam and South India), the smooth Indian Otter, L. perspicillata (through­out country), the Hog-Badger, Arctonyx collaris (Assam and eastern Himalayas); the Ratel, Mellivora capensis (From the base of the Himalayas to Cape Comorin).

The common mongoose Herpestes edwarsi (throughout India); the small Indian civet, Viverricula indica (Peninsular India) belong to the family Viverridae. Felidae include larger and smaller cats of which the Asiatic lion, Panthera leo persica; the Tiger P. tigris tigris; the Leopard, P. pardus, the Snow leopard, P. uncia (Kashmir to Bhutan); the Clouded leopard, Neofelis nebulosa (Assam and Sikkim); the Golden cat, Felis temmincki (Assam); the jungle cat, F. chaus (Indian peninsula); the Caracal, F. caracal (Punjab, Rajasthan, U.P., Central India) and the Lynx, F. lynx (Ladakh), etc.

Order 9:

Proboscidea is represented by a single species—Elephas maximus (Indian elephant).

Order 10:

Sirenia includes dugong or sea cow, Dugong dugon, is found in the coastal water of the Gulf of Manner and has recorded from Digha coast.

Order 11:

Perissodactyla is represented by two species—the Great one-horned Indian rhinoceros, Rhinoceros unicornis (Assam and North Bengal) and Asiatic wild ass, Asinus hemionus (Little Rann of Kutch).

The great one-horned Indian rhinoceros, Rhinoceros unicornis, javan rhinos, Rhinoceros sondaicus, and Asiatic two- horned rhinos, Rhinoceros (= Dicerorhinus) sumatrensis were found in India about 100 years ago. R. sondaicus was recorded from Manipur in 1874 and from Sundarbans areas in 1890.

An entire skeleton of R. sondaicus has collected from the river of Sundarbans in 2000. R. sumatrensis inhabi­ted Assam, Bhutan and northern Bengal in 1880. At present only R. uniconnis is seen in some pockets of Assam and N. Bengal.

Order 12:

Artiodactyla contain wild pigs, camels, chevrotains or mouse deer, deer, wild cattle, sheep, goats, goatantelopes, antelopes etc. The Indian wild boar, Sus scrota (throughout India); the one- humped camel, camelus dromedarius (drier parts of Rajasthan); the Mouse deer, Tragulus meminna (southern India); the Barking deer, Muntiacus muntjak (Peninsular India); the musk deer, Moschus moschiferus (the Himalayas); the Gaur Bos gaurus (Hill forests of India); the yak, B. grunniens (Ladak); the wild buffalo, Bubalus bubalis (Assam, wes­tern parts of Orissa, M.P.); the Nilgai, Boselaphus tragocamelus (Peninsular India except eastern India); the Shapu, ovis orientalis (Ladak, the Punjab, the Gilgit); the Marcopolo’s sheep, O. ammon polii (Hunza); the Bluesheep, Pseudois nayaur (Ladak, Kumaon); the Markhor, Capra falconeri (Kashmir); the Nilgiri tahr, Hemitragus hylocrius (Nilgiris to Anaimalais and Western Ghats); the Takin, Budorcas taxi- color (Mishmi Hills, Bhutan Himalayas); the Chinkara, Gazella gazella (North-western and Central India); the Black buck, Antelope cervicapra (Plains of Indian Peninsula); and the Chowsingha, Tetracerus quadricornis (wooded and hilly tracts of Indian Peninsula) belong to the order.