Question

Why do less than half of the frogspawn that a female frog lays live to turn into frogs?

Answer 1

The female frog lays the eggs into the water and then the male frog secretes semen at the same place i.e. in frogs external fertilisation takes place. Due to which no care of the zygote or fertilised eggs is taken unlike in internal fertilisation. Moreover they have to fetch their nutrition from outside. Also it sometimes happens that big fishes may engulf the eggs. Hence, only less than half of the frogspawn that a female frog lays live to turn into adult frogs.

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