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The drinking bird is a heat engine that exploits a temperature difference to convert heat energy to a pressure difference within the device, and performs mechanical work. Like all heat engines, the drinking bird works through a thermodynamic cycle. The initial state of the system is a bird with a wet head oriented vertically.
A freshwater aquatic food web. The blue arrows show a complete food chain (algae → daphnia → gizzard shad → largemouth bass → great blue heron). A food web is the natural interconnection of food chains and a graphical representation of what-eats-what in an ecological community.
The top-hatted “drinking bird,” once a fixture in science classrooms for demonstrating the basics of thermodynamics, is making a surprising comeback — as the inspiration for a new clean ...
White-throated dipper (C. cinclus). Dippers are small, chunky, stout, short-tailed, short-winged, strong-legged birds. The different species are generally dark brown (sometimes nearly black), or brown and white in colour, apart from the rufous-throated dipper, which is brown with a reddish-brown throat patch.
The trophic level of an organism is the number of steps it is from the start of the chain. A food web starts at trophic level 1 with primary producers such as plants, can move to herbivores at level 2, carnivores at level 3 or higher, and typically finish with apex predators at level 4 or 5. The path along the chain can form either a one-way ...
An example of a topological food web (image courtesy of USDA) [1]. The soil food web is the community of organisms living all or part of their lives in the soil. It describes a complex living system in the soil and how it interacts with the environment, plants, and animals.
Then the food passes into the gizzard (also known as the muscular stomach or ventriculus). The gizzard can grind the food with previously swallowed grit and pass it back to the true stomach, and vice versa. In layman's terms, the gizzard 'chews' the food for the bird because it does not have teeth to chew food the way humans and other mammals do.
A few bird species are specialist kleptoparasites, while many others are opportunistic. Skuas (including jaegers) and frigatebirds rely heavily on chasing other seabirds to obtain food. Other species—including raptors, gulls, terns, coots, and some ducks and shorebirds—do so opportunistically.