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A tadpole or polliwog (also spelled pollywog) is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found in adult amphibians such as a lateral line, gills and swimming tails.
The evolution of tetrapods began about 400 million years ago in the Devonian Period with the earliest tetrapods evolved from lobe-finned fishes. [1] Tetrapods (under the apomorphy-based definition used on this page) are categorized as animals in the biological superclass Tetrapoda, which includes all living and extinct amphibians, reptiles, birds, and mammals.
But, for as intriguing as frogs giving birth to live tadpoles may be, PLOS One says since researchers haven't witnessed their birth in the frog's natural environment, there's still the possibility ...
The behavior of an amphibian hatchling, commonly referred to as a tadpole, is controlled by a few thousand neurons. [4] 99% of a Xenopus hatchling's first day after hatching is spent hanging from a thread of mucus secreted from near its mouth will eventually form; if it becomes detached from this thread, it will swim back and become reattached, usually within ten seconds. [4]
Frogs have a two-stage life cycle, with the aquatic tadpole larva metamorphosing into the adult form. This tadpole was in the late stages of metamorphosis. Adults of this species are a similar ...
In developmental biology, animal embryonic development, also known as animal embryogenesis, is the developmental stage of an animal embryo. Embryonic development starts with the fertilization of an egg cell (ovum) by a sperm cell (spermatozoon). [1] Once fertilized, the ovum becomes a single diploid cell known as a zygote.
The eggs hatch into aquatic larvae called tadpoles that have tails and internal gills. They have highly specialised rasping mouth parts suitable for herbivorous, omnivorous or planktivorous diets. The life cycle is completed when they metamorphose into adults. A few species deposit eggs on land or bypass the tadpole stage.
The loss of some tadpoles in the metamorphosis from tadpole to frog is a unique feature of R. darwinii. This observation is likely explained by these hypotheses: The tadpoles that did not survive were converted into nutrition for the foster male and he digested them. [13] The tadpoles died in the vocal sac of the foster male.