Robert L Nudds

..Nevertheless, our analyses suggest that it is probable that this bird was both volant and capable of diving to some degree using either foot-propelled or, perhaps, both its wings and its feet for underwater locomotion...

..It is likely that a suite of factors, such as ecology, posture, gait, leggedness and foot morphology, will subtly affect an organism's ability to negotiate gradients...

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..Within the wing, variations in underlying bone and feather lengths nevertheless may, in altering the joint positions, permit a range of different flight styles by facilitating variation in upstroke kinematics...

..It may be that grounded running is just an artefact of treadmill studies. Research investigating the speeds used by animals in the field is sorely needed...

..Alternatively, if they were only gliders, then the flapping wing stroke must have appeared after the divergence of Confuciusornis, likely within the enantiornithine or ornithurine radiations...

..A homogenous study of the mechanical cost of terrestrial locomotion across a broad range of species, body sizes, and importantly locomotor postures is a priority for future research...

..e. flight so dominates bat locomotor morphology that other locomotor abilities tend to be derivative...

..Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture...

..While the mechanisms underlying these energetic differences are unclear, future studies should be wary when pooling male and female data...

..Although the tail of bats is different from that of birds, in that it is only divided from the wings by the legs, it nonetheless, may, in addition to its prey capturing function, fulfil a similar role in aiding flight control...