Thursday, March 16, 2017

Frog: Systematic position, Habit and habitat

Systematic Position
Phylum          :            Chordata
Sub-Phylum :              Vertebrate
Class              :            Amphibia
Genus            :            Rana
Species          :            tigrina
New Name    :             Hoplobatracus  tigerinus
Habitat
Frog lives in or near permanent fresh water bodies like lakes, ponds, rivers etc. It lives near water mainly for two reasons:
a) To keep skin moist for cutaneous respiration and
b) To escape away from enemies by jumping in water.
However, during rainy season they are found far away from water bodies.

Habit
Frogs are non-poisonous, harmless and silent animals. It shows following habits;
     a. Resting :- Frog rests on land with its short forelimbs upright and hind-limbs folded as 
           'Z' i.e. in squatting position.


 b. Locomotion:- Frog shows two types of locomotion, leaping on land and swimming in       water.
 (i) Leaping :- Frog leaps or jumps by suddenly extending the powerful and muscular hind-limbs which acts as springs throwing the body up in air. On landing back fore limbs act as shock absorber. The fore limbs also play role to maintain direction.
(ii) Swimming :- Frog swims in water by powerful backward strokes of its hind-limbs during it, toes are spread apart and broad web push against water, moving the body fore ward.  
 c. Feeding:- Frogs are carnivorous and feeds upon insects, worms, snails and
           tadpoles. Tadpoles feed upon algae as they are herbivorous.
      Some large frogs feed upon small Frogs and this mechanism is called as                     cannibalism( A type of feeding mechanism in which an individual of a species
      feeds upon the another individual of the same species).
 d. Hibernation and aestivation:-  Being cold-blooded or poikilotherermic animal, body 
      temperature of frog changes with that of the environment. Thus Frog spends inactive
      life during extreme cold or hot periods. During it, Frogs burry in soft mud and remain 
      metabolically inactive, stop feeding and respires only through skin. Energy for life 
      processes is obtained from glycogen and fat stored in their bodies. This inactive life 
     spend by frogs during winter or cold is called as "hibernation or winter sleep" while 
     during summer or hot is called as "summer sleep or aestivation"
 e.   Croaking :-    The special sound produced by male frogs during breeding season to attract female is called as croaking. It is also called as mating call. It is advertisement of home and husband.
 f. Camouflage: - Frogs can change the colour of their skin to match with that of the surroundings to protect it from enemies. This protective colouration is known as camouflage. It is also called as metachrosis. It is possible due to change in concentration of chromatophores.
 g  Breeding :- The breeding season of frog is rainy season which lasts form July to         September.
 h.   Enemies:-      The chief enemies of frogs are snakes, turtles, crows, vultures etc.