Teratornithidae

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Teratornithidae
Temporal range: Late Oligocene-Late Pleistocene
~25–0.010  Ma
Giant Condor.jpg
Teratornis merriami skeleton from the La Brea tar pits
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Cathartiformes
Family: Teratornithidae
L. H. Miller 1909
Genera

Teratornis
Aiolornis
Argentavis
Cathartornis
Oscaravis
Taubatornis

Contents

Teratornithidae is an extinct family of very large birds of prey that lived in North and South America from the Late Oligocene to Late Pleistocene. They include some of the largest known flying birds. It's members are known as teratorns.

Taxonomy

Teratornithidae are related to New World vultures (Cathartidae, syn. Vulturidae). [1] So far, at least seven species in six genera have been identified:

Description and ecology

Despite their size, there is little doubt that even the largest teratorns could fly. Visible marks of the attachments of contour feathers can be seen on Argentavis wing bones. This defies some earlier theories that extant condors, swans, and bustards represent the size limit for flying birds. The wing loading of Argentavis was relatively low for its size, a bit more than a turkey's, [5] and if there were any significant wind present, the bird could probably get airborne merely by spreading its wings, just like modern albatrosses. South America during the Miocene probably featured strong and steady westerly winds, as the Andes were still forming and not yet very high.

T. merriami was small enough (relatively speaking) to take off with a simple jump and a few flaps. The fingerbones are mostly fused as in all birds, but the former index finger has partially evolved into a wide shelf at least in T. merriami, and as condors have a similar adaptation, probably in other species, too. Wing length estimates vary considerably but more likely than not were at the upper end of the range, because this bone structure bears the load of the massive primaries.

Studies on condor flight suggest that even the largest teratorns were capable of flight in normal conditions, as modern large soaring birds rarely flap their wings regardless of terrain. [8]

Traditionally, teratorns have been described as large scavengers, very much like oversized condors, owing to considerable similarity with condors. However, the long beaks and wide gapes of teratorns are more like the beaks of eagles and other actively predatory birds than those of vultures. Most likely teratorns swallowed their prey whole; Argentavis could technically swallow up to hare-sized animals in a single piece. Although they undoubtedly engaged in opportunistic scavenging, they seem to have been active predators most of the time. [5] Teratorns had relatively longer and stouter legs than Old World vultures; thus it seems possible that teratorns would stalk their prey on the ground (much like extant caracaras), and take off only to fly to another feeding ground or their nests; especially Cathartornis seems well-adapted for such a lifestyle. Argentavis may have been an exception, as its sheer bulk would have made it a less effective hunter, but better adapted to taking over other predators' kills. As teratorns were not habitual scavengers, they most likely had completely feathered heads, unlike vultures.

The skull features of teratorns still share a lot of crucial similarities with specialized scavenging raptors. Many old world vultures possess large bills similar to teratorns, and a longer bill is in fact an anatomic feature that points toward a scavenging rather than a predatory life style, as this allow them to probe deeper into large carcases - larger than those fed upon by active-hunting raptors. Other anatomical features, such as the relatively small and sideward facing orbits and the lower skull, are also consistent with a scavenging live style. More sideward facing eyes allow scavenging raptors to have a wider field of vision, which is advantageous in spotting carcases. In contrast, predatory raptors usually have proportionally larger and more forward facing orbits, as depth perception is more important for a predatory lifestyle. [9] [10]

As in other large birds, a clutch probably had only one or two eggs; the young would be cared for more than half a year, and take several years to reach maturity, probably up to 12 years in Argentavis. [11]

See also

Related Research Articles

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Condor is the common name for two species of New World vultures, each in a monotypic genus. The name derives from the Quechua kuntur. They are the largest flying land birds in the Western Hemisphere.

<span class="mw-page-title-main">New World vulture</span> Family of birds

Cathartidae, known commonly as New World vultures or condors, are a family of birds of prey consisting of seven extant species in five genera. It includes five extant vultures and two extant condors found in warm and temperate areas of the Americas. They are known as "New World" vultures to distinguish them from Old World vultures, with which the Cathartidae does not form a single clade despite the two being similar in appearance and behavior as a result of convergent evolution.

<span class="mw-page-title-main">Black vulture</span> New World vulture

The black vulture, also known as the American black vulture, Mexican vulture, zopilote, urubu, or gallinazo, is a bird in the New World vulture family whose range extends from the southeastern United States to Perú, Central Chile and Uruguay in South America. Although a common and widespread species, it has a somewhat more restricted distribution than its compatriot, the turkey vulture, which breeds well into Canada and all the way south to Tierra del Fuego. It is the only extant member of the genus Coragyps, which is in the family Cathartidae. Despite the similar name and appearance, this species is not closely related to the Eurasian black vulture, an Old World vulture, of the family Accipitridae. For ease of locating animal corpses, black vultures tend to inhabit relatively open areas with scattered trees, such as chaparral, in addition to subtropical forested areas and parts of the Brazilian pantanal.

<span class="mw-page-title-main">King vulture</span> Large bird found in Central and South America

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<i>Argentavis</i> Extinct genus of very large birds

Argentavis is an extinct genus of teratornithids known from three sites in the Epecuén and Andalhualá Formations in central and northwestern Argentina dating to the Late Miocene (Huayquerian), where a good sample of fossils have been obtained. The type species, A. magnificens, is sometimes called the giant teratorn. It was among the largest flying birds ever to exist. While it is still considered the heaviest flying bird of all time, Argentavis was likely surpassed in wingspan by Pelagornis sandersi, which is estimated to have possessed wings some 20% longer than Argentavis and which was described in 2014.

Aiolornis incredibilis is an extinct species of teratorn bird from the western United States. Only fragmentary remains have been found, which are dated between the Early Pliocene (Zanclean) and Late Pleistocene. First described as Teratornis incredibilis by Howard in 1952 based on a cuneiform bone, the species has been moved to the new genus Aiolornis by Campbell, Scott and Springer in 1999. The generic name is derived from the ancient Greek words aiolus and ornis. Aiolus refers to the Greek god of the wind, and ornis means "bird". The specific name incredibilis means ‘incredible’. A. incredibilis is lesser-known than its close relative, Teratornis merriami, even though A. incredibilis was significantly larger. It presumably became extinct at the same time as the other megafauna in North America.

<i>Titanis</i> Genus of terror bird (Phorusrhacidae)

Titanis is a genus of phorusrhacid, an extinct family of large, predatory birds, in the order Cariamiformes that inhabited the United States during the Pliocene and earliest Pleistocene. The first fossils were unearthed by amateur archaeologists Benjamin Waller and Robert Allen from the Santa Fe River in Florida and were named Titanis walleri by ornithologist Pierce Brodkorb in 1963, the species name honoring Waller. The holotype material is fragmentary, consisting of only an incomplete right tarsometatarsus and phalanx, but comes from one of the largest phorusrhacid individuals known. In the years following the description, many more isolated elements have been unearthed from sites from other areas of Florida, Texas, and California. It was classified in the subfamily Phorusrhacinae, which includes some of the last and largest phorusrhacids like Devincenzia and Kelenken.

<i>Osteodontornis</i> Extinct genus of birds

Osteodontornis is an extinct seabird genus. It contains a single named species, Osteodontornis orri, which was described quite exactly one century after the first species of the Pelagornithidae was. O. orri was named after Santa Barbara Museum of Natural History paleontologist Phil C. Orr, for his recognition of the importance of the specimen.

<i>Teratornis</i> Extinct genus of birds

Teratornis was a genus of huge North American birds of prey—the best-known of the teratorns—of which, two species are known to have existed: Teratornis merriami and Teratornis woodburnensis. A large number of fossil and subfossil bones, representing more than 100 individuals, have been found in locations in California, Oregon, southern Nevada, Arizona, and Florida, though most are from the Californian La Brea Tar Pits. All remains except one Early Pleistocene partial skeleton from the Leisey Shell Pit near Charlotte Harbor, Florida date from the Late Pleistocene, with the youngest remains dating from the Pleistocene–Holocene boundary.

<span class="mw-page-title-main">Cathartiformes</span> Order of birds

The Cathartiformes order of scavenging birds includes the New World vultures and the now-extinct Teratornithidae. Unlike many Old World Vultures, this group of birds lack talons and musculature in their feet suitable to seize prey. In the past, they were considered to be a sister group to the storks of the order Ciconiiformes based on DNA–DNA hybridization and morphology. However, a 2021 analysis of mitochondrial genes suggested a stronger phylogenetic relationship between Cathartiformes and subfamilies of Accipitriformes.

<i>Kelenken</i> Extinct genus of birds

Kelenken is a genus of phorusrhacid, an extinct group of large, predatory birds, which lived in what is now Argentina in the middle Miocene about 15 million years ago. The only known specimen was discovered by high school student Guillermo Aguirre-Zabala in Comallo, in the region of Patagonia, and was made the holotype of the new genus and species Kelenken guillermoi in 2007. The genus name references a spirit in Tehuelche mythology, and the specific name honors the discoverer. The holotype consists of one of the most complete skulls known of a large phorusrhacid, as well as a tarsometatarsus lower leg bone and a phalanx toe bone. The discovery of Kelenken clarified the anatomy of large phorusrhacids, as these were previously much less well known. The closest living relatives of the phorusrhacids are the seriemas. Kelenken was found to belong in the subfamily Phorusrhacinae, along with for example Devincenzia.

<i>Pelagornis</i> Extinct genus of birds

Pelagornis is a widespread genus of prehistoric pseudotooth birds. These were probably rather close relatives of either pelicans and storks, or waterfowl, and are placed here in the order Odontopterygiformes to account for this uncertainty.

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<i>Cathartornis</i> Extinct genus of birds

Cathartornis is an ancient bird of the Teratornithidae family. It lived somewhere between 23 million years and 10,000 years ago. The only evidence of the bird's existence is a few bones. Its remains were documented in 1910. Cathartornis was described on the basis of 2 tarsometatarsi, 1 complete and 1 containing only the distal end, recovered from the Pleistocene La Brea Tar Pits in Southern California. Since then, no other fossils have officially been referred to the taxon, though some fossils assigned to Teratornis could be from Cathartornis and unpublished remains have been mentioned.

Buteogallus daggetti, occasionally called "Daggett's eagle" or the "walking eagle", is an extinct species of long-legged hawk which lived in southwest North America during the Pleistocene. Initially believed to be some sort of carrion-eating eagle, it was for some time placed in the distinct genus Wetmoregyps, named for Alexander Wetmore. It probably resembled a larger version of the modern-day savanna hawk, with its long legs possibly used like the secretarybird of Africa to hunt for small reptiles from a safe distance. It died out about 13,000 years ago.

Oscaravis olsoni, of the teratorn family, was a large, predatory bird that roamed the territory that is now modern-day Cuba before going extinct at the end of the Pleistocene era. Previously classified as Teratornis olsoni, it has recently been granted a new genus due to its ecological isolation from others in the teratorn family, as well as differences in size and possibly behavior. Although no exact measurements can be stated, due to recent archaeological findings and the comparison of O. olsoni bone lengths with that of other teratorns, it has been concluded Oscaravis olsoni would have had a body bigger than Taubatornis campbelli but smaller than Cathartornis gracilis.

<i>Coragyps occidentalis</i> Extinct species of New World vulture

Coragyps occidentalis, the Pleistocene black vulture, is an extinct species of New World vulture that lived throughout North and South America during the Pleistocene. It was formerly thought to be the ancestor to the modern black vulture, but is now thought to have evolved from it; the modern black vulture is paraphyletic with respect to it.

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<i>Dynatoaetus</i> Extinct genus of birds of prey

Dynatoaetus is an extinct genus of large bird of prey from the Pleistocene of Australia. It is among the largest known raptors of the region, second only to the Haast's eagle of New Zealand, with estimates suggesting a weight of up to 12 kg (26 lb). Although most closely related to modern vultures, it shows clear adaptations towards an active predatory lifestyle in the form of robust, powerful talons. This may either hint at it retaining these ancestral features from the closely related serpent eagles or show that it convergently evolved these features as it took on a similar lifestyle. Due to their size and robust bones, it is thought that Dynatoaetus would have been capable of taking large prey items like kangaroos, giant wombats and flightless birds. There are two species within the genus, the type species Dynatoaetus gaffae and the somewhat smaller Dynatoaetus pachyosteus, both of which inhabited the same part of Australia at the same time.

References

  1. Chatterjee, Sankar; Templin, R. Jack Jr.; Campbell, Kenneth E. (July 24, 2007). "The aerodynamics of Argentavis, the world's largest flying bird from the Miocene of Argentina". Proceedings of the National Academy of Sciences. 104 (30): 12398–12403. doi: 10.1073/pnas.0702040104 . PMC   1906724 . PMID   17609382.
  2. 1 2 Miller, Loye H. (1909). "Teratornis, a new avian genus from Rancho La Brea". University of California Publications, Bulletin of the Department of Geology. 5: 305–317.
  3. Campbell, Kenneth E. Jr. & Stenger, Allison T. (2002): A New Teratorn (Aves: Teratornithidae) from the Upper Pleistocene of Oregon, USA [ permanent dead link ]. pp. 1–11. in Zhou, Z. and F. Zhang. Proceedings of the 5th Symposium of the Society of Avian Paleontology and Evolution Beijing, 1–4 June 2000. China Science Press, Beijing.
  4. Howard, Hildegarde (1952). "The prehistoric avifauna of Smith Creek Cave, Nevada, with a description of a new gigantic raptor". Bull. S. Calif. Acad. Sci. 51: 50–54.
  5. 1 2 3 4 Campbell, Kenneth E. Jr. & Tonni, E. P. (1983). "Size and locomotion in teratorns" (PDF). Auk . 100 (2): 390–403. doi:10.1093/auk/100.2.390.
  6. Osborne, Hannah (July 7, 2014). "Pelagornis Sandersi: World's Biggest Bird Was Twice as Big as Albatross with 24 feet (7.3 m) Wingspan". International Business Times . Archived from the original on July 7, 2014. Retrieved July 7, 2014.
  7. S. L. Olson and H. M. F. Alvarenga. 2002. A new genus of small teratorn from the Middle Tertiary of the Taubaté Basin, Brazil (Aves: Teratornithidae). Proceedings of the Biological Society of Washington 115(4):701-705
  8. Williams, H. J.; Shepard, E. L. C.; Holton, Mark D.; Alarcón, P. a. E.; Wilson, R. P.; Lambertucci, S. A. (10 July 2020). "Physical limits of flight performance in the heaviest soaring bird". Proceedings of the National Academy of Sciences. 117 (30): 17884–17890. Bibcode:2020PNAS..11717884W. doi: 10.1073/pnas.1907360117 . PMC   7395523 . PMID   32661147.
  9. Si, Guangdii; Dong, Yiyi; Ma, Yujun; Zhang, Zihui (2015). "Shape Similarities and Differences in the Skulls of Scavenging Raptors". Zoological Science. 32 (2): 171–177. doi:10.2108/zs130253. PMID   25826066. S2CID   23236232.
  10. Potier, Simon (2020). "Visual Adaptations in Predatory and Scavenging Diurnal Raptors". Diversity. 12 (10): 400. doi: 10.3390/d12100400 .
  11. Palmqvist, Paul & Vizcaíno, Sergio F. (2003). "Ecological and reproductive constraints of body size in the gigantic Argentavis magnificens (Aves, Theratornithidae) from the Miocene of Argentina" (PDF). Ameghiniana. 40 (3): 379–385.