This timeline of the evolution of life outlines the major events in the development of life on the planet Earth. Dates given are estimates based on scientific evidence.
In biology, evolution is the ... > more
Companion dog usually describes a dog that does not work, providing only companionship as a pet, rather than usefulness by doing specific tasks. Many of the toy dog breeds are used only for the ... > more
A tendon (or sinew) is a tough band of fibrous connective tissue that connects muscle to bone, or muscle to muscle and is designed to withstand tension. Tendons are similar to ligaments except that ... > more
Yellow fever (also called yellow jack, black vomit, or sometimes American Plague) is an acute viral disease. It is still an important cause of hemorrhagic illness in several African and South ... > more
The Common Chimpanzee, also known as the Robust Chimpanzee, is a great ape. Colloquially, it is often called the chimpanzee (or simply "chimp"), though technically this term refers to both species in ... > more
Cloning is the process of creating an identical copy of an original organism or thing. A cloning in the biological sense, therefore, is a molecule, single cell (like bacteria, lymphocytes etc.) or ... > more
The Bonobo (Pan paniscus), until recently usually called the Pygmy Chimpanzee and less often the Dwarf or Gracile Chimpanzee, is one of the two species comprising the chimpanzee genus, Pan. The other ... > more
Chagas disease is a human tropical parasitic disease which occurs in the Americas, particularly in South America. Its pathogenic agent is a flagellate protozoan named Trypanosoma cruzi, which is ... > more
Color vision is the capacity of an organism or machine to distinguish objects based on the wavelength (or frequency) of the light they reflect or emit. A 'red' apple does not emit red light. Rather, ... > more
Toucans are near passerine birds from the neotropics. They are brightly marked and have enormous colorful bills. The family includes six genera and about 40 species.
Toucans range in size from 18 to ... > more