Feathers have long been regarded as the innovation that drove the success of birds.
However, feathers have been reported from close dinosaurian relatives of birds, and now …

Modern birds are typified by the presence of feathers, complex evolutionary innovations that
were already widespread in the group of theropod dinosaurs (Maniraptoriformes) that …

Uncertainties in the phylogeny of birds (Avialae) and their closest relatives have impeded
deeper understanding of early theropod flight. To help address this, we produced an …

Pterosaurs were the first vertebrates to achieve true flapping flight, but in the absence of
living representatives, many questions concerning their biology and lifestyle remain …

Recently, the marine habitat has been under pollution threat, which impacts many human
activities as well as human life. Increasing concerns about pollution levels in the oceans and …

Countershading was one of the first proposed mechanisms of camouflage [1, 2]. A dark
dorsum and light ventrum counteract the gradient created by illumination from above …

Asymmetrical feathers have been associated with flight capability but are also found in
species that do not fly, and their appearance was a major event in feather evolution. Among …

Morphology of keratinised toe pads and foot scales, hinging of foot joints and claw shape
and size all inform the grasping ability, cursoriality and feeding mode of living birds …

Body shape is a fundamental expression of organismal biology, but its quantitative
reconstruction in fossil vertebrates is rare. Due to the absence of fossilized soft tissue …

This chapter will cover clade definitions, the relationships within clades as well as the
occasional controversial relationships between different clades. Phylogenies arising from a …