Kelenken is an extinct genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of giant flightless predatory bird

Bird

Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s of the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Phorusrhacidae

Phorusrhacidae

Phorusrhacids , colloquially known as "terror birds" as the larger species were apex predators during the Miocene, were a clade of large carnivorous flightless birds that were the dominant predators in South America during the Cenozoic, 62–2 million years ago. They were roughly 1–3 meters tall...

 or "terror birds".

These birds lived in the Middle Miocene

Middle Miocene

The Middle Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene....

, some 15 million years ago, in Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 along with Argentavis

Argentavis

Argentavis magnificens is the largest flying bird ever discovered. This bird, sometimes called the Giant Teratorn, is an extinct species known from three sites from the late Miocene of central and northwestern Argentina, where a good sample of fossils has been obtained.The humerus of...

. With a skull

Skull

The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...

 28 inches (71 cm) long (including its 18 inch, 45.7 cm beak

Beak

The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...

), it had the largest head of any known bird. The tarsometatarsus

Tarsometatarsus

The tarsometatarsus is a bone that is found in the lower leg of certain tetrapods, namely birds.It is formed from the fusion of several bones found in other types of animals, and homologous to the mammalian tarsal and metatarsal bones...

was about 45 cm long .

Size

Kelenken was one of the largest carnivorous birds of all time, possibly reaching 2.28 to 3 meters (7.5 to 10 feet) tall and weighing around 500 pounds (226.8 kg).

Diet

It was a large, flightless carnivore which probably chased down and killed its prey with several bone-shattering blows from its beak. Another possibility is that it may have picked up its prey item, then proceeded to shake it vigorously to break its back, or simply deliver a fatal bite from its massive beak. Or it could have been a scavenger, driving off other animals with its size.

External links

• size comparison to a human