It is generally accepted that most non-mammal tetrapods have a hinge-like jaw operation restricted to vertical opening and closing movements. Many mammal jaw joints, by contrast, operate in more complex, three-dimensional ways, involving not only vertical, but also propalinal (rostro-caudal) and transverse (lateral) movements. Data on intraoral food processing in lissamphibians and sauropsids has prompted a generally accepted view that these groups mostly swallow food unreduced, and that in those cases where lissamphibians and sauropsids chew, they mostly use simple vertical jaw movements for food processing. The exception to that generally accepted view being some propalinal chewing in sauropsids. We combined 3D kinematics and morphological analyses from biplanar high-speed video fluoroscopy and micro-CT to determine how the paedomorphic salamander Siren intermedia treats captured food. We discovered that S. intermedia not only uses intraoral food processing, but that the elaborated morphology of its jaw joint facilitates mandibular motions in all three planes, resulting in complex three-dimensional chewing. Thus, our data challenge the commonly held view that complex three-dimensional chewing movements are exclusive to mammals, by suggesting that complex chewing mechanisms might evolved early in tetrapod evolution.

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Infectious bronchitis virus (IBV) is a highly contagious disease of birds causing significant economic losses globally. Unvaccinated scavenging chicken may serve as a source of infection for the commercial poultry farms and hence controlling the disease relying only on vaccinating commercial flocks resulted in poor achievement. The objective of this study was to determine the prevalence of IB among village chickens scavenging in Ada'a district, Ethiopia. The study area was selected for the fact that most of the commercial farms are present and thus characterized by a high density of poultry breeding. Eleven peasant associations (PA) from a total of 22 Ada'a districts were selected purposefully considering their close proximity to the large commercial poultry farms. The study was conducted on a total of 426 adult unvaccinated scavenging village chickens and sera were analyzed by an indirect ELISA test. The overall seroprevalence found in this particular study was 64.79%. Among the villages, the highest seroprevalence of IBV was detected at Yatu and Kality villages reaching up to 93.9% and 92.3% and mean antibody titer of 7097.32 and 8942.95 respectively. Given the high prevalence observed in the study area suggests an urgent need for the development of preventive and control strategies against IB not only for commercial farms but also it should consider the scavenging chicken for better achievement.