PARENTAL CARE AMPHIBIA Definition This is a process
PARENTAL CARE: AMPHIBIA
Ø Definition: This is a process by which parents give attention to the developing eggs so that they can lead independent life, thus ensuring the possibilities of the survival of the species.
PROTECTION BY NESTS, NURSERIES OR SHELTERS Ø Selection of site – Many amphibians lay eggs in protected moist microhabitats on land. Many tropical frogs and toads lay eggs on land near water. Many tree frogs lay their eggs not on land but on leaves and branches over hanging water. E. g. Rhachophorus, Hylodes. Ø Defending eggs or territories- Males of green frog Rana clamitans and other species maintain territories and attack small intruders to defend eggs. Male or female even guards the eggs.
sp Triton sp lay eggs undersurfaces of leaves overhanging on pond rain washes down to the water where metamorhosis takes palce Ø Foam nests – Many amphibians convert copious mucous secretions into nests for their young. Ø Mud Nests – In Brazilian tree frog Hyla fabre, the male digs a little crater-like hole or nursery in mud in shallow water, in which the female lays her eggs. Ø Tree nests – The south American tree frogs Phyllomedusa hypochondrales, lays eggs in a folded leaf nest with margins glued together by cloacal secretion. Ø Hylodeds
DIRECT CARRYING BY PARENT Ø Coiling around eggs in congo eel, Amphuima and certain caecilians, the female lays large eggs in burrows in damp soil and carefully guards them by coiling her body around them until they hatched. Ø Transferring tadpoles to water – some species of small frogs in both tropical Africa and South America, the hatching tadpoles fasten themselves to the back of one of the parent with their sucker like mouth and transported to water. Ø Eggs glued to body – Many amphibians, instead of remaining with the eggs, carry the eggs glued to their body. Eg. Dusky salamender
Ø Nest of gelatinous bag: Ø 7. Salamandra sp lays eggs in gelatinous bags. Ø 8. Shoot nest: Triton sp collects the shoot and lay eggs within the shoot and rain wash out the eggs. Ø Parents are directly involved: Without structural modiications of te body: Ø Eggs are carried on brood pouch within which eggs hatch into Tadeole. Ø Alytes sp a mid wife toad the mal carries the egss on his back. Ø Desmognathus sp the female carries the eggs mass tied down on her neck. Ø Ichthyophis sp te female coils round the eggs underground within decomposed
Ø Eggs in back pouches- In marsupial frogs or toads, the female carries the eggs on her back, either in an open oval depression, a closed pouch or in individual pockets. Ø Viviparity – Some anurans are ovoviviparous. They retain eggs in the oviducts and the females gives birth to living young.
Ø With structural modification: Ø Gastrotheca sp carries eggs in brood pouch, during breeding season by hormonal action formed on the back of the female. Ø Cryptobranchus sp carried eggs in brood pouch later developed in belly. Ø Pipa sp during amplexion the uterus of the female isverted and malepresses the egss into the brood pouches where they develop into tadepole larvae Ø R. darwinni the tadepole develops within the vocal sac of male.
BENEFITS OF PARENTAL CARE Ø It is important for survival of young one. Ø It improves offspring quality in a way that leads to increased offspring survival and reproduction in the future when parents are no longer associated with offspring.
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