Feathers are one of the integument appendages that form the outer covering, or plumage, on birds. The goslings hatch with a downy coat of feathers formed in embryonic development. They moult the natal plumage into juvenile feathers between 3-5 weeks of age and than moult that juvenile plumage into adult plumage between 8-11 weeks of age. Feather weight of an adult goose makes up about 6.2% of i...

Feathers are complex assemblages of multiple morphological innovations. Recent research on the development and evolution of feathers has produced new insights into the origin and diversification of the morphological innovations in feathers. In this article, I review and discuss the contribution of three different factors to the evolution of morphological innovations in feathers: feather tubular...

Microbodies associated with fossil feathers, originally attributed to microbial biofilm, have been reinterpreted as melanosomes: pigment-containing, eukaryotic organelles. This interpretation generated hypotheses regarding coloration in non-avian and avian dinosaurs. Because melanosomes and microbes overlap in size, distribution and morphology, we re-evaluate both hypotheses. We compare melanos...

background one group of significant enzymes produced by bacillus genus are alkaline proteases with several important applications in the daily life as well as common industries such as food, detergents, leather, alcohol and beer production and medical and sanitary industries, beside wastewater treatment, , biotransformation, hydrolyzed proteins and oil manufacturing. objectives in this paper, k...

STUDIES of the regeneration of feathers after plucking show the existence of considerable differences in the time intervals before the commencement of regeneration in individual feathers. In normal moulting, the development of the new feather starts before the old feather is shed, and as growth of the new feather continues and it emerges from the follicle, it may frequently be seen projecting w...

Some nonavian theropod dinosaurs were at least partially covered in feathers or filamentous protofeathers. However, a complete understanding of feather distribution among theropod dinosaurs is limited because feathers are typically preserved only in lagerstätten like that of Solnhofen, Germany or Liaoning, China. Such deposits possess clear taphonomic biases toward small-bodied animals, limitin...

The present study was aimed at isolating a potential keratinase producing bacteria from chicken feathers collected from poultry waste sites in and around Coimbatore, Tamil Nadu, and optimising the parameters for the enzyme production. The strain was identified as Bacillus licheniformis KMBVP based on 16srRNA gene sequencing. The strain showed high keratinolytic activity when cultured in feather...

Penguin feathers are highly modified in form and function, but there have been no fossils to inform their evolution. A giant penguin with feathers was recovered from the late Eocene (~36 million years ago) of Peru. The fossil reveals that key feathering features, including undifferentiated primary wing feathers and broad body contour feather shafts, evolved early in the penguin lineage. Analyse...

Covert-feathers-inspired passive flow control is beneficial for aerodynamic performance at post-stall angles of attack. However, most studies model covert feathers as a rigidly attached or freely moving flap on wing. The mounted via torsional spring, emblematic to the finite stiffness bird feathers, has remained unexplored. We simulate strongly coupled fluid-structure interactions past stationa...

Melanin is the main pigment in animal coloration and considerable variation in the concentrations of the two melanin forms (pheo- and eumlanin) in pigmented tissues exists among populations and individuals. Melanin-based coloration is receiving increasing attention particularly in socio-sexual communication contexts because the melanocortin system has been hypothesized to provide a mechanistic ...