IWOCE RC PBC 2019

 
Welcome to International Workshop on Open Component Ecosystems 

Bat 



Bats are mammals of the order Chiroptera;[a] with their forelimbs adapted as wings, they are the only mammals naturally capable of true and sustained flight. Bats are more manoeuvrable than birds, flying with their very long spread-out digits covered with a thin membrane or patagium. The smallest bat, and arguably the smallest extant mammal, is Kitti's hog-nosed bat, which is 2934 mm (1.141.34 in) in length, 15 cm (5.91 in) across the wings and 22.6 g (0.070.09 oz) in mass. The largest bats are the flying foxes and the giant golden-crowned flying fox, Acerodon jubatus, which can weigh 1.6 kg (4 lb) and have a wingspan of 1.7 m (5 ft 7 in).

Bats provide humans with some benefits, at the cost of some threats. Bat dung has been mined as guano from caves and used as fertiliser. Bats consume insect pests, reducing the need for pesticides. They are sometimes numerous enough to serve as tourist attractions, and are used as food across Asia and the Pacific Rim. They are natural reservoirs of many pathogens, such as rabies; and since they are highly mobile, social, and long-lived, they can readily spread disease. In many cultures, bats are popularly associated with darkness, malevolence, witchcraft, vampires, and death.
The delicate skeletons of bats do not fossilise well, and it is estimated that only 12% of bat genera that lived have been found in the fossil record. Most of the oldest known bat fossils were already very similar to modern microbats, such as Archaeopteropus (32 million years ago). The extinct bats Palaeochiropteryx tupaiodon (48 million years ago) and Hassianycteris kumari (55 million years ago) are the first fossil mammals whose colouration has been discovered: both were reddish-brown.
The phylogenetic relationships of the different groups of bats have been the subject of much debate. The traditional subdivision into Megachiroptera and Microchiroptera reflected the view that these groups of bats had evolved independently of each other for a long time, from a common ancestor already capable of flight. This hypothesis recognised differences between microbats and megabats and acknowledged that flight has only evolved once in mammals. Most molecular biological evidence supports the view that bats form a natural or monophyletic group.
In the 1980s, a hypothesis based on morphological evidence stated the Megachiroptera evolved flight separately from the Microchiroptera. The flying primate hypothesis proposed that, when adaptations to flight are removed, the Megachiroptera are allied to primates by anatomical features not shared with Microchiroptera. For example, the brains of megabats have advanced characteristics. Although recent genetic studies strongly support the monophyly of bats, debate continues about the meaning of the genetic and morphological evidence.
The head and teeth shape of bats can vary by species. In general, megabats have longer snouts, larger eye sockets and smaller ears, giving them a more dog-like appearance, which is the source of their nickname of "flying foxes". Among microbats, longer snouts are associated with nectar-feeding. while vampire bats have reduced snouts to accommodate large incisors and canines.
As in other mammals, and unlike in birds, the radius is the main component of the forearm. Bats have five elongated digits, which all radiate around the wrist. The thumb points forward and supports the leading edge of the wing, and the other digits support the tension held in the wing membrane. The second and third digits go along the wing tip, allowing the wing to be pulled forward against aerodynamic drag, without having to be thick as in pterosaur wings. The fourth and fifth digits go from the wrist to the trailing edge, and repel the bending force caused by air pushing up against the stiff membrane. Due to their flexible joints, bats are more manoeuvrable and more dexterous than gliding mammals.
When not flying, bats hang upside down from their feet, a posture known as roosting. The femurs are attached at the hips in a way that allows them to bend outward and upward in flight. The ankle joint can flex to allow the trailing edge of the wings to bend downwards. This does not permit many movements other than hanging or clambering up trees. Most megabats roost with the head tucked towards the belly, whereas most microbats roost with the neck curled towards the back. This difference is reflected in the structure of the cervical or neck vertebrae in the two groups, which are clearly distinct. Tendons allow bats to lock their feet closed when hanging from a roost. Muscular power is needed to let go, but not to grasp a perch or when holding on.
With its extremely thin membranous tissue, a bat's wing can significantly contribute to the organism's total gas exchange efficiency. Because of the high energy demand of flight, the bat's body meets those demands by exchanging gas through the patagium of the wing. When the bat has its wings spread it allows for an increase in surface area to volume ratio. The surface area of the wings is about 85% of the total body surface area, suggesting the possibility of a useful degree of gas exchange. The subcutaneous vessels in the membrane lie very close to the surface and allow for the diffusion of oxygen and carbon dioxide.

 

 

 

 

 

 
 
 

Member of IWOCE RC PBC 2019:



Professor

Roberto Di Cosmo


Definitions of different ecosystems


Research Proposal


Software Component Definition


History alternative energy


Enabling  technologies


Renewable energy vs non-renewable energy


Relatively new concepts for alternative energy


Research alternative energy


Disadvantages alternative energy



RC PBC
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