Energy harvesting that are able to operate in higher temperature gradients, and that can conduct electricity well without also conducting heat (something that was until recently thought impossible ), will result in increased efficiency. Future work in thermoelectrics could be to convert wasted heat, such as in automobile engine combustion, into electricity. This type of harvesting is based on the changing capacitance of vibration-dependent capacitors. Vibrations separate the plates of a charged variable capacitor, and mechanical energy is converted into electrical energy. Electrostatic energy harvesters need a polarization source to work and to convert mechanical energy from vibrations into electricity. The polarization
Feathers: The Evolution of a Natural Miracle murres if they are not on water). He then explains how the structure of feathers is waterproofing, keeping birds dry in wet conditions. Hanson interviews John Sullivan, an experienced fly fisher who explains the role of feathers in fly fishing. Later, Hanson explains the history and use of feathers in quill pens, which he uses as an example of how feathers have been adapted for other purposes beyond their natural evolutionary purposes. Hanson also describes his experience observing the behavior of vultures in Kenya, in which he discusses the lack of feathers on the heads of vultures. Hanson interviews Kimberly