Class: General Characters, Mammals classification , Adaptation.

General characteristics, Classification, Aquatic adaptation, Arboreal mammals, Cursorial and Fossorial Adaptation in Mammals,

1. 3 . Introduction to class - Mammalia . 3.1 Salient features of class Mammalia with two examples (names only) – Rat, Rabbit. 3.2 Egg laying mammals. 3.3 Aquatic adaptations in mammals. 3.4 Flying adaptations in mammals. 3.5 Cursorial and fossorial adaptation in mammals Dethe V.D

2. Mammals are one of the most evolved in the vertebrata. They are found all over and have adapted well to their surroundings. C haracterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or hair, and three middle ear bones.

3. Salient features of class Mammalia Mammals (from  Latin   mamma , 'breast') Mammals possess mammary or milk glands, Sweat gland and Sebaceous gland. Mammals are Homoeothermic animals. Give birth to their younger ones.(Viviparous). They have two pairs of limbs, adapted for walking, running, climbing, burrowing, swimming and flying. The skin of mammals has hair or fur. External ear or pinnae are present

4. https://images.app.goo.gl/dP1xAUvD8ruWh4DL7 Limbs in mammals .

5. Presence of region of the brain known as Neocortex. They are heterodont Mammals also possess cervical vertebrae. The skull is dicondylic .

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7. Heart is four chambered. The sinus venous and renal portal system are absent. Blood red in colour (RBC,WBC) Respiration is by lungs. Muscular diaphragm separating the thorax and abdomen.

8. https://images.app.goo.gl/SkpYxDFTjXMzQdYw6 https://images.app.goo.gl/ujj52Ut9t4U1VVhY9

9. The brain is well developed and divided into cerebrum, cerebellum and medulla. 12 pairs of cranial nerves. Olfactory (CN I), Optic (CN II), Oculomotor (CN III), Trochlear (CN IV), Trigeminal (CN V), Abducent (or abducens ; CN VI), Facial (CN VII), Vestibulocochlear (CN VIII), Glossopharyngeal (CN IX), Vagus (CN X), Accessory (CN XI), And hypoglossal (CN XII).

10. Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Rodentia Family: Muridae Genus: Rattus Species: R. rattus Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Lagomorpha Family: Leporidae Genus : Oryctolagus Species: Oryctolagus cuniculus https://en.wikipedia.org/

11. https://surprisetest.com/

12. Egg laying mammals. The mammals can lay eggs also. They are known as Monotrems. Monotreme , (order Monotremata ), M ember of the egg-laying mammalian order Monotremata , which includes the amphibious duck billed- platypus ( family Ornithorhynchidae ) and the terrestrial echidnas ( family Tachyglossidae )

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14. Aquatic adaptations in mammals. Types of Aquatic mammals. 1 . Completely aquatic mammals. 2. Semi-aquatic or amphibious mammals.

15. Completely aquatic mammals. l ive their entire life in the water. For Ex. W hales , Dolphins or manatees. They never come to land and are completely live in water Dolphins Blue whale Manatees

16. Cetacea : Whales , dolphins , porpoises Sirenia : Dugongs , manatees

17. Amphibious mammals These mammals do not live permanently in water. They live on land but go into water for food and shelter. seals, otters, and hippopotamuses etc.

18. Amphibious mammals ORDERS/Groups Monotremata : Ornithorhynchus (Platypus ) Marsupialia : Chironectes Artiodactyla : Hippopotamus Pinnipidia : Walruses ,otters, seals , sea lions Rodentia : Beavers , Musk rats

19. Adaptations in Amphibious mammals Small external ears , Flat tail. Webbed feet, S lender body Elongated snout  Subcutaneous fat

20. I mportant Aquatic adaptations Body shape: tapering and stream lined body. Locomotory Organ : flipper (swimming paddles ), dorsal fin, tail flukes. Integument : blubber (fatty layer of adipose tissue, loss of skin gland. Skeleton Modification: Modification of skull bone, Cervical vertebrae are fused, Endoskeleton is light. Lungs : Highly elastic & non lobular, allow the animal to stay under water for a longer period .

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22. Physiological Adaptation 1. Thermoregulation 2.  Feeding Habits 3. Osmoregulation 4. Growth and Size https://images.app.goo.gl/4uciJUjcQhBxaY7C6

23. Flying adaptations in mammals Arboreal mammals are able to climb the trees a nd modes of aerial locomotion or flight-gliding, soaring and flapping . Gliding  :   Adaptation: Limbs are long and equal, patagium (Skin Fold), streamlined body, Tapered Tail Examples: https://images.app.goo.gl/HvUxaG1YoNf11u6r5 Phalangers Order Marsupialia Flying Squirrels Order Rodentia Flying lemurs Order Dermoptera

24. Flying Mammals and Adaptations (Flapping ) Adaptation : Wings: patagia are thin with elastic membranes, The muscles and other body structures in bats to support and operate the wings , Bats: O rder Chiroptera https://images.app.goo.gl/Qqs4sW652YJAmCYE7

25. Cursorial and fossorial adaptation in mammals Cursorial Adaptation: ( limbs adapted for running). This is important for speed on hard surface The body of cursorial animals is stream­lined and spindle-shaped.  Loss of clavicle in mammals, which allows the scapula to move forwards and backwards with the limb and thereby increase stride length . Increased limb bone length Reduction or loss of digits. Hooves, hoof-like claws, or blunt claws for traction

26. https://images.app.goo.gl/xwaJgepKgsC3W6Ez9 https://images.app.goo.gl/mmTfRwC9L5kgDibM8

27. Fossorial adaptation A dapted for use in burrowing. i . Animal digging the soil for food. e.g., elephant, swine,  ii. Animals digging for retreats but seek their food above the ground. e.g., fox, mongoose iii. Animals digging for retreat but find their food under the ground. e.g., Rattus etc . Body is fusiform or spin­dle shaped Head is tapering, skull is conical (e.g., spiny ant-eater, moles and shrews).  https://www.notesonzoology.com/

28. Incisor Teeth : The incisor teeth are upturned protruded and helps in digging in pocket gopher. The tusks in elephant also help in digging . Canine Teeth : In swine, canines are effec­tive digging instrument and in others it becomes reduced . Functions of the Limbs: strong fore limbs is well suited for dig­ging into the soil