Phorusrhacidae
Encyclopedia
Phorusrhacids colloquially known as "terror birds" as the larger species were apex predator
s during the Miocene
, were a clade
of large carnivorous flightless bird
s that were the dominant predators in South America
during the Cenozoic
, 62–2 million years (Ma) ago. They were roughly 1–3 meters (3–10 feet) tall. Their closest modern-day relatives are believed to be the 80 cm-tall seriema
s. Titanis walleri, one of the larger species, is known from Texas
and Florida
in North America
. This makes the phorusrhacids the only known example of large South American predators migrating north during the Great American Interchange
(which occurred after the volcanic Isthmus of Panama
land bridge
rose ca. 3 Ma ago). It was once believed that T. walleri only became extinct around the time of the arrival of humans in North America, but subsequent datings of Titanis fossils have failed to provide evidence for their survival more recently than 1.8 Ma ago.
Possible phorusrhacid remains have recently been recovered from the Eocene
of Algeria
.
A recently discovered species, Kelenken guillermoi
from Middle Miocene
some 15 million years ago, discovered in Patagonia
in 2006, represents the largest bird skull
yet found. The fossil has been described as being a 71 cm (28 in), nearly intact skull. The beak is roughly 46 cm (18.1 in) long and curves in a hook shape that resembles an eagle's beak. Most species described as phorusrhacid birds were smaller, 60–90 cm (2–3 ft) tall, but the new fossil belongs to a bird that probably stood about 3 m (9.8 ft) tall. Although scientists cannot be sure, they theorize that the large terror birds were extremely nimble and quick runners able to reach speeds of 48 km/h (29.8 mph).
and 18 species
:
Alvarenga and Höfling did not include the Ameghinornithidae from Europe in the phorusrhacoids; these have meanwhile turned out to be more basal members of Cariamae. Though traditionally considered as members of the Gruiformes
, based on both morphological and genetic studies (the latter being based on the seriema) that they may belong to a separate group of birds (the Cariamae) and their closest living relatives are the Falconidae
, Psittaciformes and the Passeriformes
Apex predator
Apex predators are predators that have no predators of their own, residing at the top of their food chain. Zoologists define predation as the killing and consumption of another organism...
s during the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
, were a clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
of large carnivorous flightless bird
Flightless bird
Flightless birds are birds which lack the ability to fly, relying instead on their ability to run or swim. They are thought to have evolved from flying ancestors. There are about forty species in existence today, the best known being the ostrich, emu, cassowary, rhea, kiwi, and penguin...
s that were the dominant predators in South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
during the Cenozoic
Cenozoic
The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...
, 62–2 million years (Ma) ago. They were roughly 1–3 meters (3–10 feet) tall. Their closest modern-day relatives are believed to be the 80 cm-tall seriema
Seriema
The seriemas are the sole extant members of the small and ancient family Cariamidae, which is also the sole surviving family of the Cariamae. Once believed to be related to cranes, they have been placed by one recent study near the falcons, parrots and passerines, as well as the extinct terror birds...
s. Titanis walleri, one of the larger species, is known from Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
and Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
. This makes the phorusrhacids the only known example of large South American predators migrating north during the Great American Interchange
Great American Interchange
The Great American Interchange was an important paleozoogeographic event in which land and freshwater fauna migrated from North America via Central America to South America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor and bridged the formerly separated continents...
(which occurred after the volcanic Isthmus of Panama
Isthmus of Panama
The Isthmus of Panama, also historically known as the Isthmus of Darien, is the narrow strip of land that lies between the Caribbean Sea and the Pacific Ocean, linking North and South America. It contains the country of Panama and the Panama Canal...
land bridge
Land bridge
A land bridge, in biogeography, is an isthmus or wider land connection between otherwise separate areas, over which animals and plants are able to cross and colonise new lands...
rose ca. 3 Ma ago). It was once believed that T. walleri only became extinct around the time of the arrival of humans in North America, but subsequent datings of Titanis fossils have failed to provide evidence for their survival more recently than 1.8 Ma ago.
Possible phorusrhacid remains have recently been recovered from the Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
of Algeria
Algeria
Algeria , officially the People's Democratic Republic of Algeria , also formally referred to as the Democratic and Popular Republic of Algeria, is a country in the Maghreb region of Northwest Africa with Algiers as its capital.In terms of land area, it is the largest country in Africa and the Arab...
.
A recently discovered species, Kelenken guillermoi
Kelenken
Kelenken is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds".These birds lived in the Middle Miocene, some 15 million years ago, in Argentina along with Argentavis. With a skull 28 inches long , it had the largest head of any known bird...
from Middle Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
some 15 million years ago, discovered in Patagonia
Patagonia
Patagonia is a region located in Argentina and Chile, integrating the southernmost section of the Andes mountains to the southwest towards the Pacific ocean and from the east of the cordillera to the valleys it follows south through Colorado River towards Carmen de Patagones in the Atlantic Ocean...
in 2006, represents the largest bird 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...
yet found. The fossil has been described as being a 71 cm (28 in), nearly intact skull. The beak is roughly 46 cm (18.1 in) long and curves in a hook shape that resembles an eagle's beak. Most species described as phorusrhacid birds were smaller, 60–90 cm (2–3 ft) tall, but the new fossil belongs to a bird that probably stood about 3 m (9.8 ft) tall. Although scientists cannot be sure, they theorize that the large terror birds were extremely nimble and quick runners able to reach speeds of 48 km/h (29.8 mph).
Systematics and taxonomy
Following the revision by Alvarenga and Höfling (2003), there are now 5 subfamilies, containing 14 generaGenus
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...
and 18 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
:
- Subfamily Brontornithinae — gigantic species, standing over 2.3 metres (7.5 ft) high. Placement in Phorusrhacidae and/or monophyly disputed.
- Genus BrontornisBrontornisBrontornis was a genus of giant flightless predatory birds that lived in Patagonia. The only species currently accepted as valid is B. burmeisteri...
(Early - Middle Miocene) - Genus ParaphysornisParaphysornisParaphysornis is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds" and the subfamily brontornithinae that lived in Brazil. Its length was about 2 meter and the skull had a length of 60 centimeter. The only known species is Paraphysornis...
(Late Oligocene/Early Miocene of São Paulo State, Brazil) - Genus PhysornisPhysornisPhysornis is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds" that lived in Argentina. The only known species is Physornis fortis. It lived from 28 to 23 million years ago....
(Middle - Late Oligocene of Santa Cruz Province, Argentina)
- Genus Brontornis
- Subfamily Phorusrhacinae — giant species 3.2 metres (10.5 ft) high, but somewhat slender and decidedly more nimble than the Brontornithinae
- Genus DevincenziaDevincenziaDevincenzia is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds" that lived from 7 till 5 million years ago in Argentina and Uruguay during the late miocene and early pliocene. D. pozzi was formally known as Onactornis pozzi. It stood about 2,5...
(Late MioceneMioceneThe Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
- Early PliocenePlioceneThe Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
of NE ArgentinaArgentinaArgentina , 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...
and Arroyo Roman, UruguayUruguayUruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area...
) - Genus KelenkenKelenkenKelenken is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds".These birds lived in the Middle Miocene, some 15 million years ago, in Argentina along with Argentavis. With a skull 28 inches long , it had the largest head of any known bird...
(Middle MioceneMioceneThe Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
of Río Negro province, ArgentinaArgentinaArgentina , 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...
(largest known phorusrhacid)) - Genus PhorusrhacosPhorusrhacosPhorusrhacos was a genus of giant flightless predatory birds that lived in Patagonia, containing the single species Phorusrhacos longissimus. Their closest living relatives are the much smaller seriema birds...
(Early - Middle Miocene) - Genus TitanisTitanisTitanis is a large extinct flightless carnivorous bird of the family Phorusrhacidae, endemic to North America during the Blancan stage of the Pliocene living 4.9—1.8 Ma, and died out during the Gelasian Age of the earliest Pleistocene, existing approximately .-Etymology:The generic name, Titanis,...
(Early Pliocene - Early Pleistocene)
- Genus Devincenzia
- Subfamily Patagornithinae — intermediate sized and very nimble species, standing around 1.7 metres (5.6 ft) high
- Genus PatagornisPatagornisPatagornis is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds" that lived in Argentina....
(Santa Cruz Early - Middle Miocene of Santa Cruz Province, Argentina) - includes Morenomerceraria, Palaeociconia, Tolmodus - Genus AndrewsornisAndrewsornisAndrewsornis is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds" that lived in Argentina....
(Middle - Late Oligocene of S Argentina) - Genus AndalgalornisAndalgalornisAndalgalornis was a genus of flightless predatory birds of the family Phorusrhacidae that lived in Argentina. The type and only species is A. steulleti....
(Late Miocene - Early Pliocene)
- Genus Patagornis
- Subfamily Psilopterinae — small species, standing 70–100 cm (2.3–3.3 ft) high
- Genus PsilopterusPsilopterusPsilopterus is an extinct genus of phorusrhacid from the Middle Oligocene to Late Miocene of Argentina. Compared to other phorusrhacids, members of the genus are both relatively gracile and diminutive, and include the smallest known species of terror bird: with the head raised P...
(Deseado Middle Oligocene - Arroyo Chasicó Late Miocene of S and E Argentina) - Genus ProcariamaProcariamaProcariama is an extinct Monotypic genus of giant flightless predatory birds in the family Phorusrhacidae or "terror birds" which lived in Argentina....
(Late Miocene - Early Pliocene of Catamarca Province, Argentina) - Genus PaleopsilopterusPaleopsilopterusPaleopsilopterus is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds" and the subfamily of the psilopterinae that lived 60 million years ago in Brazil during the middle paleocene. The only known species is Paleopsilopterus itaboraiensis....
(Middle Paleocene of Itaboraí, Brazil)
- Genus Psilopterus
- Subfamily Mesembriornithinae — medium-sized species, standing between 1.2–1.5 m (3.9–4.9 ft) high
- Genus MesembriornisMesembriornisMesembriornis is a genus of intermediate-sized phorusrhacids that grew up to 1.5 meters in height. They represent a well-distinct lineage of terror birds, differing from the massive large groups and the smaller Psilopterinae...
(Late Miocene - Late Pliocene)
- Genus Mesembriornis
Alvarenga and Höfling did not include the Ameghinornithidae from Europe in the phorusrhacoids; these have meanwhile turned out to be more basal members of Cariamae. Though traditionally considered as members of the Gruiformes
Gruiformes
The Gruiformes are an order containing a considerable number of living and extinct bird families, with a widespread geographical diversity. Gruiform means "crane-like"....
, based on both morphological and genetic studies (the latter being based on the seriema) that they may belong to a separate group of birds (the Cariamae) and their closest living relatives are the Falconidae
Falconidae
The falcons and caracaras are around 60 species of diurnal birds of prey that make up the family Falconidae. The family is divided into two subfamiles, Polyborinae, which includes the caracaras and forest falcons, and Falconinae, the falcons, kestrels and falconets.-Description:Falcons and...
, Psittaciformes and the Passeriformes
Synonyms
The family Phorusrhacidae have been described under a number of synonyms:- Phororhacosidae Ameghino, 1889
- Pelecyornidae Ameghino, 1891
- Brontornithidae MorenoFrancisco MorenoFrancisco Pascacio Moreno was a prominent explorer and academic in Argentina, where he is usually referred to as Perito Moreno...
& Mercerat, 1891 - Darwinornithidae Moreno & Mercerat, 1891
- Stereornithidae MorenoFrancisco MorenoFrancisco Pascacio Moreno was a prominent explorer and academic in Argentina, where he is usually referred to as Perito Moreno...
& Mercerat, 1891 - Phororhacidae LydekkerRichard LydekkerRichard Lydekker was an English naturalist, geologist and writer of numerous books on natural history.-Biography:...
, 1893 (unjustified emendationEmendation (taxonomy)In biological classification, emendation is a scientific change to the name of a living organism, intended to improve its classification....
) - Patagornithidae Mercerat, 1897
- Hermosiornidae Rovereto, 1914
- Psilopteridae Dolgopol de Saez, 1927
- Devincenziidae Kraglievich, 1932
- Hermosiorniidae Kraglievich, 1932 (unjustified emendationEmendation (taxonomy)In biological classification, emendation is a scientific change to the name of a living organism, intended to improve its classification....
) - Mesembriorniidae Kraglievich, 1932
- Hermosiornithidae WetmoreAlexander WetmoreFrank Alexander Wetmore was an American ornithologist and avian paleontologist.-Life:Wetmore studied at the University of Kansas...
, 1934 (unjustified emendationEmendation (taxonomy)In biological classification, emendation is a scientific change to the name of a living organism, intended to improve its classification....
)
External links
- Hooper Museum
- Terror Birds: Bigger and Faster (ScienceScience (journal)Science is the academic journal of the American Association for the Advancement of Science and is one of the world's top scientific journals....
) - Darren Naish: Tetrapod Zoology: "terror birds"
- Darren Naish: Tetrapod Zoology: "Raven, the claw-handed bird, last of the phorusrhacids" includes links to other articles on phorusrhacids