The Horusornithidae are a prehistoric family of birds of prey. They are part of the Falconiformes

Falconiformes

The order Falconiformes is a group of about 290 species of birds that comprises the diurnal birds of prey. Raptor classification is difficult and the order is treated in several ways.- Classification problems :...

. Their name means "Horus

Horus

Horus is one of the oldest and most significant deities in the Ancient Egyptian religion, who was worshipped from at least the late Predynastic period through to Greco-Roman times. Different forms of Horus are recorded in history and these are treated as distinct gods by Egyptologists...

-birds": the Egyptian god Horus was sometimes depicted as a falcon

Falcon

A falcon is any species of raptor in the genus Falco. The genus contains 37 species, widely distributed throughout Europe, Asia, and North America....

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Horusornis vianeyliaudae is presently the only known species. It lived approximately at the end of 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...

, some 35 mya in what today is France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

. Its fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

s were found in Quercy

Quercy

Quercy is a former province of France located in the country's southwest, bounded on the north by Limousin, on the west by Périgord and Agenais, on the south by Gascony and Languedoc, and on the east by Rouergue and Auvergne....

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The relationships between falcons and other birds of prey (such as hawk

Hawk

The term hawk can be used in several ways:* In strict usage in Australia and Africa, to mean any of the species in the subfamily Accipitrinae, which comprises the genera Accipiter, Micronisus, Melierax, Urotriorchis and Megatriorchis. The large and widespread Accipiter genus includes goshawks,...

s and eagle

Eagle

Eagles are members of the bird family Accipitridae, and belong to several genera which are not necessarily closely related to each other. Most of the more than 60 species occur in Eurasia and Africa. Outside this area, just two species can be found in the United States and Canada, nine more in...

s) are not resolved to satisfaction. Horusornis may have been a "missing link

Missing Link

Missing link is a nonscientific term for any transitional fossil, especially one connected with human evolution; see Transitional fossil - Missing links and List of transitonal fossils - Human evolution.Missing Link may refer to:...

" uniting falcons, hawks, and the secretarybird. If falcons are more distantly related to other birds of prey, the horusornithids would rather be basal

Basal (phylogenetics)

In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...

 relatives of hawks that somewhat resembled falcons due to convergent evolution

Convergent evolution

Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...

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