Evolution Of Amphibians
The word ‘Amphibian‘ is derived from the Ancient Greek term amphíbios which means ‘both kinds of life’. Amphibians can live on both land and water, and primarily inhabit damp ground in the most diverse parts of the world. The first major groups of amphibians developed in the Devonian period, around 370 million years ago. Amphibians were the first vertebrates (i.e. they have a backbone) to develop paired limbs capable of movement on dry land, the first to have a middle ear and to have a sensory organ, localized on the palate in the mouth. They were the first animals in which the eyes were protected by eyelids. Today more than twenty five hundred species of amphibians are known.
Indian Cricket Frog
These little frogs frequent shallow marshes, flooded fields, and damp grassland near canals and ditches. When disturbed, they leap into the water and start swimming. They are mostly nocturnal during the cool or very dry months but may occasionally be found in piles of decaying vegetation or under logs and rubbish.
Bull Frog or Tiger Frog
This frog always lives near water, in weed-choked ditches, marshes, and tanks; often sitting on the banks under bushes; and is most common in habitats modified by man. During the monsoon season it is spread over flooded lowlands. It feeds on aquatic insects, snails and small frogs from its own species.
These frogs are largely aquatic, at least during the daytime. During the breeding season, the males have the thighs and throat suffused with a red color. It is endemic to Murree and its surrounding areas including the Margalla Hills National Park
This species tolerates considerable organic pollution and is most common in habitats modified by man. It inhabits clear rocky streams, muddy swamps, and reservoirs. Skittering frogs mainly prey on aquatic insects. They also feed on tadpoles of their own species. Their usual call is “crrreek, crrreek.” Adults can subsist for months in the water, spending much of their time floating on the surface. When alarmed, they skitter (move actively) across the surface of water before diving and hiding in the bottom of the pond.
Marbled Balloon Frog
This frog is known to be an excellent burrower and comes to the surface only during monsoon. It is a weak swimmer and usually floats in water. Moist soil is indispensable for this frog. During dry months, it retreats into the moist vicinity of termite nests, termites being its main food. It has been known to have lived for thirteen months without food. The breeding season of this frog extends from May to July, during monsoon rains. The call of the male is like a bleating goat; its vocal sac is distended so enormously that it looks like a float.
Marbled Toad or Indus Valley Toad
These toads bury in burrows in wet soil or sand, and remain active from March to October over most of Pakistan. Adults are often seen floating in ponds and pools, and during the monsoon season they often enter houses. They are generally nocturnal, spending the day in dark, damp holes or crevices apparently with a strong attachment, as they have been found returning to the same spot on successive days after nightly feeding forays. They are usually solitary, but in captivity a group may rest in a jumbled pile.