Written by:Mehwish Altaf

Notes BS Zoology

Animal Diversity 2nd

TERMINAL

CLASS AMPHIBIANS

419.3 million years ago

Division period

Osteolipids fish -----> travel / swim from poal to pool ---> under goes modification ---> amphibians.

  • “Animal that live dual life, land & water are called amphibians”
  • During late Devonian period a population of asteolipids fishes travel poll to pool & produce a terrestrial population that we known as amphibians.

GENERAL CHARACTERISTICS

  1. Cold- blooded animals which live on land & in aquatic environment.
  2. Body is divided into head & frunk. Tail is only present in caudate carder / ordeal.
  3. They have 2 pair of limbs which are modified for jumping & swimming.
  4. They respire by gills in larval stage & adult have lungs. Amphibians are specialize for cutaneous respiration.
  5. 3 chambered heart with 2 aurical and 1 ventricle.
  6. Well- developed digestive system present.
  7. Ribs are absent in amphibians.
  8. Excreatary organ are advanced then fishes, they have mesonephric kidney and a urinary bladder which store urine.
  9. RBCs are nucleated with haemoglobin.
  10. The urinary system and genital system is seprated in amphibian female.
  11. Sexes are sepreated.
  12. Cleavage is holoblasic and egg is telolecithal.
  13. External ear is absent middle and inner ear is present.

Classification of Indus valley Frog

Also called as Asian Bull frog ( Basanti Daddo)

Kingdom

Animalia

Phylum

Chordata

Class

Amphibia

Order

Anura

Family

Dicroglossidae

Genus

Haplobatrachur

Species

H. Tigerinus

Common Name

Indus valley bull frog.

 

 

Distribution:-

 Mainly found in India, Pakistan, Nepal, Bangladesh, and Afghanistan and act as invasive species.

Invasive Species:- Those who are nature to a sperific area or lacation.

Habitat:-

They are found near water surface and they used to live near water avoid forest areas.

  • They live in holes, burrows or in bushes of plants near water.
  • They are solitary and nocturnal in nature.

Size:- 5 – 7 cm.

Weight:- 25 – 500 grams.

Body colour:- They are greenish or aliver green in colour with dark spots vertebral line.

  • Male while young in yellowish colour. While in adult stage they turn to typicall greenish colour. Female remain green throughout the life.

Morphology

Body consists of 2 parts.

  • Amphibian (frog) contain no neck and tail. Head is pointed snout like and moderate in size.
  • 2 set if teeth are present in buccal cavity but have no function of crushing or griding.
  • Two set of limbs are present i.e, Hind limbs and fore limbs. Which are embedded with toes.
  • The limbs are used for leaping, burrowing and swimming.
  • Dorsal surface of frog is dark green with patches while ventral surface is pale white.
  • Along with eyes, frog contain nictiating membrane which prevent, the eyes when frog is in water.
  • External ear are absent in frogs instead of these tympanic membrane is present which is used for sound amphification.
  • Frog are sexually dimorphic in nature and male frog contain specialized structure called
  • Capulatory pad.
  • Vocal sac.

Capulatory Pad

are also called as thumb pad found only in male and helps in grasping the female frog during capulation.

Vocal sac:- is a flexible membrane of skin which is wed in making the advertisement call during breeding season male is ready to produce.

DIGESTIVE SYSTEM

Digestive system of Asian bull frog is derived into two components.

  • Alimentary canal
  • Digestive canal

Alimentary canal:-

  • MOUTH:-

The alimentary canal of frog is started with an opening aperture known as mouth which contain jaws

  • Upper jaws
  • Lower jaws\

Jaws are bounded with immovable lips.

BUCCAL CAVITY:-

Buccal cavity contain jaws in which upper jaws is fixed &contain set of teeth which are called “vomeric” teeth .There teeth are involve in digestive process &used only to prevent the excape of prey lower jaw is movable .

  • Long , thick & fleshy tongue is present which is attached to the lower jaw & fold up in the floor of buccal cavity .It is used to trap the prey .
  • Buccal cavity is lined up with the column epithelial cells which processes mucus secreating glands b/c digestive glands are absent in mouth mucus lubricate the food
  • Tongue contain taste buds & mucus secreating cells.

PHARNYX:-

The buccal cavity narrows behind into a structure called pharynx which open into oseophagus through structure called gullet.

In male frog pharynx contain vocal sac.

OESOPHAGUS:-

Gullet lead to short , small & reduced muscular organ of alimentary canal called esophagus. This is small & reduced part as frog contain no neck. It opens into stomach.

STOMACH:-

It is most important part of alimentary canal where the digestion of ingested food take place through digestive glands.

Stomach is divided into 2 regions

  • Inner linning of stomach posseses several folds which allow the expansion of stomach at pyloric region of stomach narrow behind & open into intestine.

INTESTINE:-

Stomach lead to a highly coiled, elongated tube like structure called intestine, which are divided into

  • Small intestine
  • Large intestine
  • Small intestine contain several loops in their structure & is highly coiled. It contain hepatopancreatic duct which is responsible for bringing digestive juices from liver & pancrease.
  • Large intestine is short & leads into a small, reduced structure rectum. Absorption of nutrients take place in this region.

CLOOCAL APERTURE:-

Rectum leads to a small sac like structure which receive opening from the anus & urino-genital operture.

 

DIGESTIVE GLAND

 

Digestive gland

Small intestine through the hepato-pancreatic duet.

 

DIGESTIVE SYSTEM

Food:-

 Amphibains feed on small invertebrates & small mammals . rodents (Rats etc)

  • Food of the frog always depend on its size . They are carnivorous
  • They wait for the prey to pass by, as the prey passed by them.
  • They captured the prey through tongue & engulf it as whole.

INGESTION:-

The amphibians ingestion occurs through predation .True tongue is first seen in amphibians . Tongue is bi-lobed & fleshy.

  • Amphibians use their jaws & tongue for capturing of their prey.
  • They wait for pass to pass by and as any prey pass near them , they capture the prey by Flicking up their tongue. Tongue is long & and is rolled up in floor of buccal cavity.
  • Capturing & swallowing process is very immediate & take only 0.05-0.15 seconds.
  • Tongue & muscles of the mouth pushes the food through towards stomach.

DIGESTION:-

  • The food when comes in stomach , process of digestion starts .The cells present in inner lining of stomach secretes mucus & initial digestion occurs here. The digestion is partial & the food is now sent to the large intestine .
  • Here in a small intestine , digestive juices are secreted through hapata-pancreatic duct .The process of digestion completes in small intestine . A little amount of absorption also takes & the digested product is sent to the large intestine where the final absorption takes place . All the nutrients & useful substances are absorbed & waste is expelled through the cloaca.

 Osmoregulation in Amphibians

 

Digestive gland

 

Water & mineral ions balance in the body. Amphibians must have need to remove or store water & conserve mineral ions.

The skin & wall of urinary bladder are responsible for transportation of internal ions.

  • The balance of water occurs through different behavior .

Diurnal:-

The terrestrial amphibians used to avoid the dry land & if they are diurnal . They find out best humid areas or moist land where they tap their body on earth’s surface & maintain water balance.

Nocturnal:-

 Some amphibians are nocturnal in nature & came out only at night .They already live in humid area to reduce the chances of water loss.

Reduce body Surface:-

Amphibians which lives in burrows & in group form used this mechanism. They fold their body & come close to each other in this way a small body area is exposed to the environment/atmosphere.

Protective Covering:-

The skin bears hard surface which is resistant to the water, when the amphibians feel the fear of the water loss they form the burrow & close the hole of burrow & close the hole of burrow with their hand body surface to reduce water loss.

Water storage:-

The amphibians have the ability to store water in their lymph sac & urinary bladder.

35% water is stored by amphibians in respond to their body weight.

Dehydration:-

Skin of amphibians is richly supplied with capillaries so they flattened the skin on moist surface & absorb water to rehydrate themselves.

Respiration in Amphibians

  • 30 % ---90% of respiration in amphibians is cutaneous .
  • Air contain 20% more oxygen than water, so the process of respiration is also important
  • There are three types of respiration in amphibians.

Cutaneous respiration:-

When the gaseous exchange occur through skin the respiration is cutaneous .The skin contain blood capillaries & involve in absorbing O2 from the atmosphere & removing the CO2 from body.

(1-7%)

Buccopharyngeal Respiration:-

The amphibians uses the mechanism of buccopharyngeal respiration in land .The respiration which takes place through the moist surface of mouth & phyrnx is buccopharyngeal.

Pulmonary respiration:-

  • The respiration through lungs is pulmonary respiration.
  • Pulmonary ventilation occur by buccal pump mechanism.
  • The muscles of mouth & phyrnx exert positive pressure with help of which air pumped to the lungs & respiration occurs.

Reproduction

Voscals:-

(1).Advertisement call by male for reproducing .

(2). Release call ===> Both male + male

(3). Recieptive call ===> Female

(4). Distress call===> both in stress or daryer .

Characteristics OF Mammals

  • Word “Mamalia” is form a Greek word which means “Mammary Gland”.
  • Class mamalia are the top of the animal kingdom.

Distribution:-

Found all over the world b/c they are cosmopolitan in nature.

  • Hair:-

The body of the mammals is covered with skin possesses hairs. The hairs are made up of keratin protein.

  • Skin Glands:-
  1. Mammary Gland:

Also called as milk gland that are functional in females , produce milk to nourish their bodies.

(b) Scent Gland:-

Also called as the fragment gland .In some mammals skin contain scent gland which produce specific fragment or scent that is used for sexual behavior .Also wed commercially.

Example:- Found in Mushlc Deer

(c) Sudoriporan Glands:-

Also called as sweat gland found in skin & used to regulate the body temperature.

(d) Sabeceaus Gland:-

Also called as the oil gland . It is present beneath the epidermic & lubricate skin & hairs to make them water proof.

Complexity OF Brain

The brain of mammals is highly folded (convulated) & cerebrum becam more/ vary complicated (completed due to this convulation) 

Mammalian Heart:- Heart consist of 4 chambers

 2 auricles

 2 ventricles

Complete heat & circulatory system is complex having no mixing of O2 &CO2 blood sinus vinosus is absent (Different from fishes).

Dentition:-

Mammals are Thecodant Diphydant & hetrodant

  • Heterdentition ===> Incisor, Canine, Molar
  • Thecodant ===> Teeth are embedded in Jaws
  • Diphydant ===> (1) Milk Teeth (2) Permanent Teeth

 Ear:-

Complete ear with fleshy external ear or pinnae is present (Different from fishes & amphibians).

Limbs:-

Mammals are tetropodes , pentadactyle.

2 pairs of limbs are present i.e , fore limbs & hind limbs which contain 05 digits some mammals also contain hooves i.e , horse , donkey.

Mammals are

Oviparous ====> Monotremres

Viviparous =====> Placentalian

 Oviviparous ====> Massupalia

 Oviparous 

(Ornythorynchus 

Anitinus) 

 Scientific name of Duck bill Platypus

 Viviparous

(Oryctolagus

caniculus)

Scientific Name of Rabbit

Oviviparous

(Macropus

refus)

Scientific

Name of Rea Kangroo

 Oviparous

  • Duck Bill Platypus scientific name is Cornythorhychus antinus
  • The mammal which lays eggs and eggs contain extra embryonic membrane from where the feotus take nourishment.
  • After hatching babies feed on milk produce by mammary gland of mother.

Viviparous

Scientific name (oryctolagus cuniculus) of Rabbit.

  • The mammals in which the embryo is completely develop after delivery the mother & after delivery the baby feed on milk produce by mother.

Ovoviviparous

Scientific name Macropus rufus of Red kangaroo

  • In some mammals the development completes in two stage.

Kangaroo are example gin which the egg contain only yolk sac so the babies draw nourishment from yolk sac .When yolk sac is utilize they born but are

  • undevelop & retain in mother body for some time when fully developed then leave mother body.

Order Monotreme

Classification:-

Kingdom -------- Animilia Phylum -------- Chordata

Sub- Phylum -------- Vertebrea

 Class -------- Mammalia 

Sub-Class -------- Prototheria

 Order -------- Monotremate

Genus -------- Ornythorhychus

 Specie -------- O. anatinus

Common Name -------- Duck Bill Platypus

Distribution:-

O.anatinus are present the bank of rivers. Size----45 cm

Feeding habitat

Carnivores == > Feed on crustoceans & small worms

Morphology:-

Head:Short , flattened head is present.

Beak:- They called duck bill platypus b/c .They have broad, flatten beak. Beak is covered with soft 7 fine skin contain sensory organs.

Teeth:- Inside beak teeth are present & the teeth are only present in childhood. In adult O.anatinus the teeth are replaced by horny plates which are presents in inner linning of beak.

LIMBS

Webbed & Clawed limbs are present hind limbs are well webbed & their web is extending form top of toes .In hind limbs spur are present while fore limbs are clawed .They have five digits.

Tail:-

Tail is broad , large & flattened

Eye:-

Bead like small rounded, eye are present on head.

Ear:- External ear are reduced , while middle & inner is present &well- developed

DEVELOPMENT:-

  • anatinum are oviparous, having rgg with extraembryonic membranes.
  • Foetus draw nutrients before birth from these embryonic membrane & after birth they feed on milk from mother.

SPUR:-

Spur is a structure that is present in hind limbs of duck bill platypus . In males the spur contain crural gland & the function of crural gland is to produce venome which used for 

  • Mating Competition
  • Prevention from predation
  • This venome cause temporary paralysis & do not cause any damage.
  • Female also contain spur but it do not contain crural gland .So spur is functionless in female ornythorhychus anatinus.

Order Massupalia

Classification

Kingdom -------- Animilia Phylum -------- Chordata

Sub- Phylum -------- Vertebrea Class -------- Mammalia

 Sub-Class -------- Theria

Infra class -------- MetaTheria Order -------- Marsupalia Genus -------- Macropus Specie -------- M.rufus

Common Name -------- Read Kangroo

Distribution:-

They originate & found in Australia .They are extinct in Pakistan. Macropus rufus is largest surviving kangaroo.

Feeding Habitats:-

They are herbivores & feed on variety of grasses b/c of grazing they have specialized type of teeth.

  • 5 incisor in upper jaw
  • 3 premolars in upper jaw
  • 4 molar in upper jaw
  • 3 incison in lower jaw
  • 3 premolars in lower jaw
  • 4 molar in lower jaw

Limbs:-

Limbs are modified running, jumping & walking .Kangaroo have short fore limb & long hind limb.

Both limbs have digits & claws.

Hind limb:-

Hind limb is long / stronger used for locomotion. Hind limbs contain only 4 digits.

  • Hallux are absent (Big toe)
  • 2nd &3rd digit in hind limb is united & 4th digit is large , highly clawed & used for defensive mechanism .

Tail:-

External ear is present on viviparous are absent

  • Tail is long & thick , having round shape & mostly called as third leg.
  • Tail is used as balancing organ.
  • Locomotion in Kangaroo is bipedal.

Development:-

Kangaroo are oviviparous mean their feotus develop in uterus with only yolk sac placenta when the yolk sac is utilized , the embryo get delivered but is not completely developed & is immature with only 2.5 cm in length -50 the baby retain in mother baby.

The bodies after delivery are transferred to marsupiam that is mother pouch where the baby feed on milk produced by mammary gland when the baby get enough mature they came out from the marsupiam

They may live in marsupian for 3-4 month.

Class Mamalia

Classification:-

Kingdom -------- Animilia

 Phylum -------- Chordata 

 Sub- Phylum -------- Vertebrea

 Class -------- Mammalia

 Sub-Class -------- Theria

 Infra class -------- Eutheria

 Order -------- Marsupalia

 Family -------- Lagomorpha Genus -------- Oryctolagus

Specie -------- O.cunculus

Common Name -------- Rabbit

Disrtribution:-

They are cosmopolition, found every where in world but their original home was Europe & Africa from where they spread or carried by man from place to place.

Habitat:-

They are gregarious in nature i.e. they live in groups even several families consisting of hundreds of rabbit which live together.

  • They live in wood lands grass land etc.
  • They digs burrow to live in it, with the help of their fore limbs they burrow a spacious tunnel, which opens in various direction.
  • At a time many rabbits inhibits this tunnel their burrow is known as “ Warren”.
  • They form warren for :-
  • Rearing their offsprings.
  • Protection form danger.

Morphology:- Body is divided into 4 parts.

  • Head 3) Trunk
  • Neck 4) Tail

Shape:- Their body is pointed auteriorly and broader posteriorly.

Size:- 16 inches in length with 2-4 pound weight.

Colour:- They are found in white colour or black colour, Sometimes white with brown or black patches.

1)Head:- Head is pointed and form snout, Head contain

Mouth:- Mouth is present on terminal of snout which is bounded by pair of moveable upper and lower lips.

Lips:- The upper lip is divided in middle and extend upwards to the nostrils.

Nostrils:- Trust above the mouth, two oblique openings are present Nostrils.

Eyes:- Pair of rounded eyes are present on either side of the head.

Ears:- External ears are present which are large, elongated and trumped shape.

Vibrissae:- On either side of nostrils, near upper lip, present, which are sensory in function.

Neck:- Neck is part of body present between the head and trunk and it is present to provide free movement of head in all direction.

  • Neck in rabbits is short, so that is why they have large ears which detect sound waves in all directions.
  • Neck is advantageous in digging of burrow.

Trunk:- Trunk is divided two region:-

  • Thorax

Thorax:- Thorax form a bony cage of ribs and sternum, cavity is called thoraciae cavity. It contain all tendor organ like heart, liver, stomach etc.

Abdomen:- Abdomen is broader body part which is enclosed in abdominal cavity.

  • Ventral side of abdomen contain 4-5 pair of nipple/teats which are functional in female only because of milk production by mammary glands.
  • The end of posterior side of abdomen contain anus which is the digestive organ in body.
  • Urino genital opening is separate in rabbits. In male it located while, In female , a slit like opening in vulva.
  • On either side of anus, a small, hairless , depression is present in rabbits, which is called perinpal pouch, a gland is present in it called perineal gland.

Perineal Gland:- Characteristic features of rabbit.

Perineal gland secreate a fluid which produce a specific and strong odour/smell in rabbit.

Rabbit and Hares:-

In Rabbit and In Hares the perineal, the absent Gland is present.

Limbs:-

In rabbits abdomen

  • Anteriorly fore limbs are present which contain
  • Upper arm ===> Brachium
  • Lower arm===>Antrbrachium
  • Wrist=== > Carpus
  • Palm === > Meta Carpus
  • Distal Hand=== > Manus with pentadactyle claws
  • Posteriorly hind limbs are present which contain
  • Proximal leg=== > Thigh
  • Middle leg == > Shank
  • Distal foot === > Pes

With Ankle (Tarcus) & soul (metatarsul) & four digits are present which are clawed.

Tail:-

Bushy small tail present at the end of trunk which is white form posterior side , Tail is used for defense during any tail for warning alarm to their companies.

 AMPHIBIANS

 Amphibians are vertebrae tetropodes . Amphibia include frogs, salamansars, & caecilians. The term amphibians loosely translate from the Greek as “ duel life” which is a reference to the metemorphpsis that many frogs & salamandars undergo & their mixture of aquatic & terrestrial environments in their life cycle.

Amphibians evolved during the Devonsion period & were the earliest terrestrial tetropodes.

Caudata

Order caudata include that amphibians which posses tail. Salamanders are the amphibians of order caudate which is also known as urodela. This taxon include group of rough skinned species of family salamandridae.

Salamanders are distinguished from other amphibians like frogs by the presence of having limbs set at right angle to the body with fore limbs & hind limbs of approximately equal in size salamanders are also distinguished from frog by numerous characteristics of their skeleton & musculature.

Anieds Vagrans

Classification:

Kingdom

Animalia

Phylum

Chordate

Sub- phylum

Urtebrata

Super-classs

Tetrapoda

Class

Amphibian

Order

Caudate

Family

Plethodonitidae

Genus

Aneides

Specie

Aneides uagrans

Common name

Wandering salamander cungles salamander

Distribution:

Aneides vagrans are mostly found in Canada & U.S Most of the species are native to western hemi share from british Columbia to Brazil & few of them found in south korea

Habit / Habitat:

The natural habitat of Aneides vagrans is temprate/ moderate. Forest it is threatened by habitat loss it can mostly live in move on land during day time of high humidity.

During day time, they hide themselves under tress while at night they feed at small invertebrates like ants, mites, beetles , snails_

Morphology

Wandering salamander is similar in appearance to the clouded salamander ( Aneides ferrus) & was consider to be the same species but they are separted recently due to same genetic evidence.

  1. A medium sized salamander is slimy long legged cadapted for climbing) with long squared off toes.
  2. They are long & slender grow form snout to went by the length of 3 inches & total length of 5 inches.
  3. They contain a rounded prehensile tail.

Prehensile Tail:

 A tail in animal that has adopted to be able to grasp & hold objects.

  1. They usually contain 16 coastal grooves and two has labial grooves.
  • Coastal Grooves:- These grooves help to keep the skin moist it is present mid dorsal to ventral region.
  • Naso-Labial Grooves:- These grooves are linned up with glands that enhance the chemoreception.
  1. The body colour is dark brown to pale gray.
  2. As they are called lungless salamander during day time they hide themselves under fallen trees and breath their through skin. So respiration in aneides vagrans occur through skin. And the tissue lining their mouth.
  3. Male and Female anedies have some point of differences. Male have more broades and triangular head than female/
  4. Reproduction is terrestrial. Breeding male have fully develop mehtal glands. Male sexually develop in the 2 years.
  5. Female lay 6-9 eggs in moist. Place on land Number of egg is variable.
  6. The youngs develop in the egg and hatch directly into a tiny salamander with the same body from as in adult.
  7. Breeding take place during spring and early summer, while youngs born in the near august Female stay with eggs until they hatch.
  8. Defence tactics or stratigies aniedes vagrans include crawling away quickly remaining matianles waving the tail and making fast Jerky movement.



View and Download More Tutorials !

Notes of Botany

Notes BS Zoology