The hindlimb myology of Milvago chimango (Polyborinae, Falconidae)

Abstract

We describe the hindlimb myology of Milvago chimango. This member of the Falconidae: Polyborinae is a generalist and opportunist that can jump and run down prey on the ground, unlike Falconinae that hunt birds in flight and kill them by striking with its talons. Due to differences in the locomotion habits between the subfamilies, we hypothesized differences in their hindlimb myology. Gross dissections showed that the myology of M. chimango is concordant with that described of other falconids, except for the following differences: the m. flexor cruris medialis has one belly with a longitudinal division; the m. iliotibialis lateralis does not have a connection with the m. iliofibularis; the m. fibularis longus is strongly aponeurotic; the m. tibialis cranialis lacks an accessory tendons and the m. flexor hallucis longus has one place of origin, instead of two. The presence of the m. flexor cruris lateralis can be distinguished as it has been described absent for the Falconidae. We associated its presence with the predominant terrestrial habit of the M. chimango. Each muscle dissected was weighed and the relationship between flexors and extensors at each joint was assessed. The extensor muscles predominated in all joints in M. chimango. Among the flexors, the m. flexor hallucis longus was the heaviest, which could be related to the importance of the use of its talons to obtain food.

Differential locomotor and predatory strategies of Gondwanan and derived Laurasian dromaeosaurids (Dinosauria, Theropoda, Paraves): Inferences from morphometric and comparative anatomical studies

“…In a general way, owls (Strigiformes) have the shortest and most robust metatarsus, whereas falconiforms and especially accipitrids have a longer and more slender metatarsus (Ward et al 2002;Einoder and Richardson, 2007;Fowler et al 2009). Thus, owls have a greater grip capacity and strength, although these abilities are also related to other characters of the foot, such as the presence of sesamoids, a specialized tendon-locking mechanism, and a facultative zygodactyl condition (Ward et al 2002;Einoder and Richardson, 2007;Fowler et al 2009 (Mosto et al 2013).…”

The Hindlimb Myology ofTyto alba(Tytonidae, Strigiformes, Aves)

“…This value agrees with that found for T. alba (13.8%) and other Strigidae (Otus choliba (10.64%), Pulsatrix perspicillata (13.6%), Strix nigrolineata (10.96%), Ciccaba virgata centralis (9.86%) and Asio clamator (16.86%); Hartman, 1961). Also, when this value, 14.13%, is compared with that of other species that also rely on their feet for obtaining food, like Falconidae or Accipitridae species, the percentage of the hindlimb muscle mass is within this range of values too, for example Milvago chimango (9.42%, Mosto et al, 2013), Falco sparverius (8.12%; Mosto, 2014), Buteogallus meridionalis (16.67%; Mosto, 2014) and Buteogallus urubitinga (15.4%, Hartman, 1961). With respect to the percentages of flexor and extensor muscles across each joint in T. alba, the flexors of the digits were the muscles with the higher mass.…”

“…This is also a condition found on diurnals birds of prey (e.g. Buteogallus urubitinga, Falco sparverius; Mosto et al, 2013;Mosto, 2014). The main difference between nocturnal and diurnal raptors is appreciated in the m. flexor digitorum longus and m. flexor hallucis longus.…”

OSTEOLOGIA CRANIANA COMPARADA E ASPECTOS EVOLUTIVOS DE Caracara cheriway (Jacquin, 1784) E Caracara plancus (Miller, 1777) (AVES: FALCONIDAE)

“…Enquanto os Falconinae (Falco entre outros) são avívores, ou seja, predam outras aves em pleno voo, matando suas presas com suas garras e bico, os Caracarinae possuem diversas estratégias de caça: Daptrius e Ibicter são onívoros e arbóreos, enquanto Milvago, Caracara, e Phalcoboenus, alimentam-se de uma dieta geralista, como invertebrados, vertebrados e carniça (FUCHS et al, 2012). Estes últimos três gêneros são em grande parte terrícolas, com características morfológicas distintas, com pernas relativamente longas e dedos curtos (MOSTO et al, 2013). Aliado a isso, C. cheriway também se alimenta de nozes, no Texas central (SKORUPPA; LEE, 2008) e C. plancus dispersa frutos de bacuri (Attalea phalerata) no Pantanal (GALETTI; GUIMARÃES, 2004).…”