Скачать или смотреть Bats use blood to reshape tongue for feeding (video s03)

Color movie of G. soricina gathering nectar. This color high-speed movie captures blood flow through the vascular sinuses and papilla erection during nectar feeding. At the beginning of tongue protrusion, notice that the vascular sinuses and papillary veins contain small amounts of blood and then become engorged with blood near maximum extension of the tongue. Playback speed is 1/16th of real speed. A close-up view of the tongue submerged in the nectar shows the same lap twice.

Reference
Specialized bat tongue is a hemodynamic nectar mop
PNAS May 6, 2013 May 6, 2013, doi: 10.1073/pnas.1222726110
http://www.pnas.org/content/early/201...

Abstract
Nectarivorous birds and bats have evolved highly specialized tongues to gather nectar from flowers. Here, we show that a nectar-feeding bat, Glossophaga soricina, uses dynamic erectile papillae to collect nectar. In G. soricina, the tip of the tongue is covered with long filamentous papillae and resembles a brush or mop. During nectar feeding, blood vessels within the tongue tip become engorged with blood and the papillae become erect. Tumescence and papilla erection persist throughout tongue retraction, and nectar, trapped between the rows of erect papillae, is carried into the mouth. The tongue tip does not increase in overall volume as it elongates, suggesting that muscle contraction against the tongue's fixed volume (i.e., a muscular hydrostat) is primarily responsible for tip elongation, whereas papilla erection is a hydraulic process driven by blood flow. The hydraulic system is embedded within the muscular hydrostat, and, thus, intrinsic muscle contraction may simultaneously increase the length of the tongue and displace blood into the tip. The tongue of G. soricina, together with the tongues of nectar-feeding bees and hummingbirds, which also have dynamic surfaces, could serve as valuable models for developing miniature surgical robots that are both protrusible and have highly dynamic surface configurations.