Post by Infinity Blade on Apr 3, 2016 9:22:05 GMT 5
Sylviornis neocaledoniae
A reconstruction of S. neocaledoniae from Worthy (2016).
Temporal range: Holocene (until 3,500 years ago[1])
Scientific classification:
Life
Domain: Eukaryota
(unranked): Unikonta
(unranked): Opisthokonta
(unranked): Holozoa
(unranked): Filozoa
Kingdom: Animalia
Subkingdom: Eumetazoa
(unranked): Bilateria
Clade: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Clade: Olfactores
Clade: Craniata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Clade: Eugnathostomata
Clade: Teleostomi
Superclass: Tetrapoda
Clade: Reptiliomorpha
Clade: Amniota
Class: Reptilia or Clade: Sauropsida
Clade: Eureptilia
Clade: Romeriida
Clade: Diapsida
Clade: Neodiapsida
Clade: Archelosauria
Clade: Archosauromorpha
Clade: Archosauriformes
Clade: Crurotarsi
Clade: Archosauria
Clade: Avemetatarsalia
Clade: Ornithodira
Clade: Dinosauromorpha
Clade: Dinosauriformes
Clade: Dinosauria
Order: Saurischia
Clade: Eusaurischia
Suborder: Theropoda
Clade: Neotheropoda
Clade: Averostra
Clade: Tetanurae
Clade: Orionides
Clade: Avetheropoda
Clade: Coelurosauria
Clade: Tyrannoraptora
Clade: Maniraptoriformes
Clade: Maniraptora
Clade: Pennaraptora
Clade: Paraves
Clade: Eumaniraptora
Clade: Averaptora
Clade: Avialae
Clade: Euavialae
Clade: Avebrevicauda
Clade: Pygostylia
Clade: Ornithothoraces
Clade: Euornithes
Clade: Orithuromorpha
Clade: Ornithurae
Clade: Neornithes
Infraclass: Neognathae
Superorder: Galloanserae
Clade: Pangalliformes
Family: †Sylviornithidae
Genus: †Sylviornis
Species: †S. neocaledoniae
Sylviornis is an extinct genus of stem galliform[2] that lived in New Caledonia during the Holocene. Only one species is known for this genus, S. neocaledoniae.
Taxonomy:
Sylviornis used to be thought of as a ratite or a megapode. However, a 2016 analysis conducted by Worthy et al. (2016) found that it forms a clade with Megavitiornis altirostris, Sylviornithidae (stem Galliformes).[2]
Mounds:
In New Caledonia, there are unusual large mounds, also known as tumuli. It was suggested that, because of Sylviornis' (erroneous) megapode affinities, it was likely the creator of the tumuli. A trademark characteristic of megapodes is the utilization of ectothermic incubation, which utilizes mounds built by the birds. But given how Sylviornis was a stem galliform instead, it is unlikely that it was the mound builder, as mound building and ectothermic incubation would have evolved twice if such was the case. Moreover, its pedal morphology suggests that at most, it could scratch the ground like a giant chicken, speaking against its ability to build the mounds.[2]
Description:
Sylviornis was the largest galliform that ever lived, weighing in at ~27-34 kilograms and ~85 centimeters tall in resting pose.[2]
Skeletal reconstruction of Sylviornis neocaledoniae from Worthy (2016). The missing skeletal parts are estimated (shaded bones), with the pelvis based on proportions of Leipoa ocellata. The bill rhamphotheca is not reconstructed so as to not obscure the underlying skeletal morphology.
Extinction:
From ~3,500 to ~700 years ago, almost 1,000 species of non-passerine terrestrial birds became extinct in the Pacific islands, including Sylviornis (this does not count non-passerine marine birds or passerines, which would make the extinction toll even greater). These extinctions have been linked to the arrival of humans, who would have overhunted birds and cleared the forests in which they resided in.[1]
References:
[1] Duncan, R.P., Boyer, A.G., Blackburn, T.M. (2013). Magnitude and variation of prehistoric bird extinctions in the Pacific. PNAS. doi: 10.1073/pnas.1216511110
[2] Worthy, T.H., Mitri, M., Handley, W.D., Lee, M.S.Y., Anderson A., & Sand C. (2016). Osteology Supports a Stem-Galliform Affinity for the Giant Extinct Flightless Bird Sylviornis neocaledoniae (Sylviornithidae, Galloanseres). PLOS ONE. doi: 10.1371/journal.pone.0150871
A reconstruction of S. neocaledoniae from Worthy (2016).Temporal range: Holocene (until 3,500 years ago[1])
Scientific classification:
Life
Domain: Eukaryota
(unranked): Unikonta
(unranked): Opisthokonta
(unranked): Holozoa
(unranked): Filozoa
Kingdom: Animalia
Subkingdom: Eumetazoa
(unranked): Bilateria
Clade: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Clade: Olfactores
Clade: Craniata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Clade: Eugnathostomata
Clade: Teleostomi
Superclass: Tetrapoda
Clade: Reptiliomorpha
Clade: Amniota
Class: Reptilia or Clade: Sauropsida
Clade: Eureptilia
Clade: Romeriida
Clade: Diapsida
Clade: Neodiapsida
Clade: Archelosauria
Clade: Archosauromorpha
Clade: Archosauriformes
Clade: Crurotarsi
Clade: Archosauria
Clade: Avemetatarsalia
Clade: Ornithodira
Clade: Dinosauromorpha
Clade: Dinosauriformes
Clade: Dinosauria
Order: Saurischia
Clade: Eusaurischia
Suborder: Theropoda
Clade: Neotheropoda
Clade: Averostra
Clade: Tetanurae
Clade: Orionides
Clade: Avetheropoda
Clade: Coelurosauria
Clade: Tyrannoraptora
Clade: Maniraptoriformes
Clade: Maniraptora
Clade: Pennaraptora
Clade: Paraves
Clade: Eumaniraptora
Clade: Averaptora
Clade: Avialae
Clade: Euavialae
Clade: Avebrevicauda
Clade: Pygostylia
Clade: Ornithothoraces
Clade: Euornithes
Clade: Orithuromorpha
Clade: Ornithurae
Clade: Neornithes
Infraclass: Neognathae
Superorder: Galloanserae
Clade: Pangalliformes
Family: †Sylviornithidae
Genus: †Sylviornis
Species: †S. neocaledoniae
Sylviornis is an extinct genus of stem galliform[2] that lived in New Caledonia during the Holocene. Only one species is known for this genus, S. neocaledoniae.
Taxonomy:
Sylviornis used to be thought of as a ratite or a megapode. However, a 2016 analysis conducted by Worthy et al. (2016) found that it forms a clade with Megavitiornis altirostris, Sylviornithidae (stem Galliformes).[2]
Mounds:
In New Caledonia, there are unusual large mounds, also known as tumuli. It was suggested that, because of Sylviornis' (erroneous) megapode affinities, it was likely the creator of the tumuli. A trademark characteristic of megapodes is the utilization of ectothermic incubation, which utilizes mounds built by the birds. But given how Sylviornis was a stem galliform instead, it is unlikely that it was the mound builder, as mound building and ectothermic incubation would have evolved twice if such was the case. Moreover, its pedal morphology suggests that at most, it could scratch the ground like a giant chicken, speaking against its ability to build the mounds.[2]
Description:
Sylviornis was the largest galliform that ever lived, weighing in at ~27-34 kilograms and ~85 centimeters tall in resting pose.[2]
Extinction:
From ~3,500 to ~700 years ago, almost 1,000 species of non-passerine terrestrial birds became extinct in the Pacific islands, including Sylviornis (this does not count non-passerine marine birds or passerines, which would make the extinction toll even greater). These extinctions have been linked to the arrival of humans, who would have overhunted birds and cleared the forests in which they resided in.[1]
References:
[1] Duncan, R.P., Boyer, A.G., Blackburn, T.M. (2013). Magnitude and variation of prehistoric bird extinctions in the Pacific. PNAS. doi: 10.1073/pnas.1216511110
[2] Worthy, T.H., Mitri, M., Handley, W.D., Lee, M.S.Y., Anderson A., & Sand C. (2016). Osteology Supports a Stem-Galliform Affinity for the Giant Extinct Flightless Bird Sylviornis neocaledoniae (Sylviornithidae, Galloanseres). PLOS ONE. doi: 10.1371/journal.pone.0150871
