The four stages of an animal's life cycle are an egg, embryo, immature individual and adult. This life cycle is true for most fish, bird, amphibians, reptiles and mammals. More »

Toxoplasma gondii start as unsporulated oocysts, turn into sporulated oocysts in the environment, which in turn become tachyzoites when ingested by an animal, states the Centers for Disease Control and Prevention. Once t... More » Science Biology

Toucans, found in and around the tropical forests of Central and South America, reach maturity within the first two months of life and can begin breeding. Toucans can live to be approximately 20 years old. More »

While the most recognizable stage of the grey wolf's life cycle is the large imposing adult, these animals go through several stages from conception to death. The average wolf lives six to eight years in the wild. It gro... More »

A head louse has a life cycle of three stages: egg, nymph and adult. Difficult to see, nits are lice eggs and are often mistaken for dandruff or hair product. Adult female lice lay nits at the base of a hair shaft close ... More » Pets & Animals Bugs

The endosperm serves as a source of nutrition for a plant embryo in a seed, somewhat analogous to the yolk of an egg for an animal embryo. It is actually, in a sense, a separate organism, with a genetic code from the com... More »

The life cycle of the cockroach includes three stages: egg, nymph and adult. These same three stages are common to insects that do not undergo metamorphosis. While temperature, species and factors from its environment af... More »