Parental care in amphibians
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This document discusses various forms of parental care exhibited by amphibians to increase offspring survival. It outlines nine types of parental care observed in amphibians: 1) selection of safe egg-laying sites, 2) frothing of water around eggs, 3) defending egg territories, 4) building nests from mud, leaves, or plant shoots, 5) direct development from egg to juvenile, 6) carrying eggs attached to the body, 7) carrying larvae between water bodies, 8) brooding eggs in vocal sacs or pouches on the back, and 9) retaining eggs internally in a uterus for viviparous development.
Parental care in amphibians
- 1. Name : Sahib Ullah
- 2. Parental Care in Amphibians:- Parental care may be defined as any behavior exhibited by a parent toward its offspring that Increases the offspring’s chances of survival (Trivers. 1972). this investment may reduce the parent’s ability to invest in additional offspring. Among amphibians, parental care Includes attendance of the eggs, transportation of eggs or larvae, and feeding of larvae.
- 3. There are various ways by which the parental care is manifested in amphibians. 1. Selection of Site: Some amphibians lay their eggs in safe and moist land, very near to water. In case of Hylodes, eggs are laid on the under surface of leaves hanging above water. In Triton the eggs may be fixed with the aquatic weeds by glues. 2. Frothing of Water: In Rhacophorus maculates, after the eggs are laid, surrounding water is made frothy by the limb movements, which prevent the eggs from desiccation and escaping from the eyes of the predators.
- 4. 3. Defending Eggs: Males of green frog Rana clamitans defend their eggs by not allowing small sized intruders in their territories. 4. Formation of Nests: Some amphibians build nests for deposition of eggs. Mud Nest: Hyla faber digs small holes in the mud for deposition and development of the eggs. Leaf Nest: In a South American tree frog Phyllomedusa hypochondrales, margin of the leaves are folded and glued together which acts as nest for the eggs. Shoot Nest: Triton construct the nest by fixing the shoots with a gelatinous secretion.
- 5. 5. Direct development: Some terrestrial or tree frogs, like Hylodes and Hyla nebulosa, the eggs hatch directly into tiny juveniles avoiding predator attach and larval mortality. 6. Carrying eggs over the body: Amphuima, Ichthyphis females after laying eggs guard them by coiling body till the eggs hatch. In Megalobatrachus, the males perform the same function.
- 6. iv) Eggs glued to the body: In Sri Lankan tree frog, Rhacophorus reticulates, the eggs are glued to the belly of the females. iv) Eggs in back pouches: In Hyla goeldii, the females carry the eggs on their back. In Pipa pipa, the eggs are carried by females on the back.
- 7. 7. Carrying eggs over the body: In Arthroleptis, the larvae are attached to the males and are carried from one water body to other. 8. Organs as brooding pouches: South American male frog of Rhinoderma darwinii keeps fertilized eggs in his vocal sacs where they undergo complete development.
- 8. 9. Viviparity: A special type of reproductive behavior is observed in Salamandra atra and S. maculosa. The eggs are placed inside the uterine cavity where the entire development takes place. The uterine wall functions physiologically as primitive placenta.