Piciformes

## About

Piciformes is the order that includes every species of toucan, toucanet, aracari, barbet, honeyguide, jacamar, puffbird and woodpecker. The order itself is not that large in terms of amount of families however, it includes 71 genera with 450 different species. Originally piciformes also included members of the hoopoe, scimitarbill and hornbill families however, these two have been separated into the order bucerotiformes. All piciformes, - with the exception of three-toed woodpeckers- have zygodactyl toes, alike to those of a parrot's, with two toes on both the front and back of the foot. As the origin of the zygodactyl is unknown, deciphering the first appearance of piciformes in the fossil record has proven a difficult task. A multitude of prehistoric taxa ranging from the Eocene is sometimes included in this order such as; Zygodactylidae, Primoscenidae, Sylphornithidae and the genus Hymolophus. Other taxa from the Miocene; Picus gaudryi and the Pliocene; Bathoceleus are also included in this category. Many fossils proven to be ancestral piciformes have been hard to place in the order and thus will not be listed in this article, due to their unclear classification. Extant piciform families can be dated back to the Oligocene period (65.5-23mya), to the early Miocene. Piciform evolution likely took place in Europe, with the only remaining family on the continent being Picidae. With this information, it can be inferred that even New World piciformes have origins in the Old World.

## Families

### Galbuli

#### Galbulidae

Galbulidae is comprised of jacamars, which were originally thought to be closer to coraciiformes. After analysis was conducted on the bird's nuclear DNA in 2003, the family was placed as a sister group to piciformes along with Bucconidae. This analysis concluded that Galbulids were in fact, were closer to piciformes than coraciiformes.

#### Bucconidae

Bucconids, or puffbirds, Are a family of New World neotropical birds. The families of Bucconidae and Galbulidae were first placed into the order piciformes in the writings of Alexander Wetmore (1886-1978), in his book; *Birds of the World*. This decision was largely supported by the families sharing morphological similarities in the form of their muscle and skeletal structure. Despite these similarities. a nuclear DNA test conducted in 2003, concluded that the families were classed as sister groups to piciformes. This lineage is sometimes known as Galbuliformes however, they are more commonly regarded as members of the glade; Galbuli.

### Pici

#### Indicatoridae

Indicatorids, also known as honeyguides or indicator birds, are a family of birds wo inhabit the Old World, predominantly in Africa and Asia. The family includes some of the only birds who can eat and digest beeswax. As African honeyguide species only eat the wax of the common bee ***(Apis mellifera)***, it is likely that this adaptation is fairly recent, likely originating 2mya. The family is split up into 4 genera which are comprised altogether of 17 species. DNA-DNA hybridisation analysis places honeyguides as close relatives to woodpeckers however, morphological similarities provide evidence towards them being more closely related to barbets.

#### Picidae

Picidae includes the last remaining piciformes to exist in Europe, the family is comprised completely of woodpeckers, which differ greatly from the tropical and neotropical birds of the other families. The family's closest relatives, Indicatoridae, comprise the clade Pici with Picidae. This placement was confirmed by DNA sequencing, which placed the birds in the same clade. Picidae is comprised of 240 species organised into 35 genera however, due to Picids having a reliance on arboreal environments, around 20 species are considered to be threatened by the acts of deforestation.

## Other Families

#### Megalaimidae

Megalaimidae is comprised of 35 species of barbets all native to areas of East and Southeast Asia. Asian barbets were originally thought to be closer to New World barbets and so were placed in the Capitonidae family however, the Old World barbets, along with Lybiidae and Ramphastidae, are considered ore accurately to be sister groups to Capitonidae. Megalaimidae can be further split into 3 genera, Caloramphus, Megalaima and Psilopogon however, Psilopogon is now more often thought to be within the genus Megalaima. Due to Psilopogon predating Megalaima, all of the Asian barbet species were moved to the genus, with the exception of the species that remain a part of Caloramphus. Members of Caloramphus are said to have diverged from other Megalaimids around 21.32mya, during the Miocene and are considered sometimes to be in their own subfamily within Megalaimidae; Caloramphinae.

#### Lybiidae

Lybiidae is comprised of the 43 species of African barbets. The family includes 7 genera being; Lybius, Gymnobucco, Stactolaema, Pogoniulus, Buccanodon, Trachyphonus and Tricholaema. There is also a eighth genus being Capitonides however, it is uncertain whether the genus should be placed under the classification of Lybiidae. Capitonides is very hard to place due to the genus being extinct, only being known form fossil evidence from the Early to middle Miocene (23-5mya). The genus only existed in Europe and due to this it has been debated in which Old World barbet family it belongs to. The Trachyphonus genus belongs to its own subfamily of Trachyphoninae and it has been debated whether the Capitonides genus should also become a member of the subfamily. The Old World barbet fossil specimen known as 'CMC 152' found in Grive-Saint-Alban, France, dated back to the middle Miocene. It apparently differed morphologically from Capitonides upon first description, due to this it is sometimes included in Trachyphonus and is likely related to extant Old World barbets. Other middle Miocene specimens found in Kohfidisch, Austria, are said to belong to the Pogoniulus genus however, it is unclear whether they belong to the extant genus, as they require further inspection.

#### Semnornithidae

Semnornithidae or the toucan barbet family, is usually considered its own distinct family however, as of recent it is starting to be known as the Semnornis genus in the Ramphastidae family. Similarly, the members of both the Old World barbet families may eventually be considered as members of the Semnornithinae subfamily of Ramphastidae. The family itself is extremely small, including only two species.

#### Capitonidae

Capitonidae, or the New World barbet family, are a family of barbets which presently inhabit Central and South America however, likely originate from Florida during the Miocene. Originally all barbet species were included in a single family however, this placing was reconsidered due to the group being paraphyletic. Capitonids are extremely closely related to toucans, as are all barbet families however, it is believed that Capitonidae and Ramphastidae evolved from a common ancestor. This evidence has led many to believe that barbets should eventually be placed into the toucan family Ramphastidae, rather than their own distinct families.

#### Ramphastidae

Ramphastidae is comprised of toucans, aracaris and toucanets, all amounting to a total of 6 genera including 41 species. As stated above, toucans likely evolved from a common ancestor with New World barbets however, they also share a close relationship with the Picidae family. No fossilised remains of the family are known, making it very hard to examine where and when Ramphastids originate however, the remains of the extant toco toucan ***(Ramphastos toco)***, found to be dated back to the Pleistocene of 20,000 years ago, suggest that the Ramphastidae family has remained in a similar state for thousands of years. Speciation (the act in which new species are created through various factors) likely occurred during this time frame, particularly during the glaciations of the time, meaning that the diverse species in the family today can likely be attributed to the mass environmental shifts of the time.

## Sources

* piciformes | Wikipedia - https://en.wikipedia.org/wiki/piciformes
* Jacamar | Wikipedia - https://en.wikipedia.org/wiki/Jacamar
* Puffbird | Wikipedia - https://en.wikipedia.org/wiki/Puffbird
* Asian Barbet | Wikipedia - https://en.wikipedia.org/wiki/Asian\_barbet
* African Barbet | Wikipedia - https://en.wikipedia.org/wiki/African\_barbet
* Semnornis | Wikipedia - https://en.wikipedia.org/wiki/Semnornis
* New World Barbet | Wikipedia - https://en.wikipedia.org/wiki/New\_World\_barbet
* Woodpecker | Wikipedia - https://en.wikipedia.org/wiki/Woodpecker
* Honeyguides (Indicatoridae) | Encyclopedia.com - https://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/honeyguides-indicatoridae
* Toucans (Ramphastidae) | Encyclopdia.com - https://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/toucans-ramphastidae