Friday, May 25, 2012

Frog Populations Have Been Rapidly Disappearing Worldwide

Frog populations have been rapidly disappearing worldwide, and nearly one-third of the world’s amphibian species are endangered and on the verge of extinction. Approximately 200 amphibian species have disappeared since 1979 – many from seemingly pristine wilderness areas, such as national parks. Amphibians are currently going extinct several thousand times faster than they should be naturally, which is why this is one of the world’s most serious and overlooked environmental crisis.

Amphibians are important for maintaining balance in the ecosystem, which allows humans to derive many direct benefits from frogs. For instance, adult frogs eat large quantities of insects, including disease vectors transmitting fatal illnesses to humans (e.g. mosquitoes/malaria). They also eat agricultural pests that would destroy crops if their populations were not kept under control. Frogs act as natural pesticides, reducing dependence on potentially harmful chemical pesticides. India and Bangladesh banned exportation of frogs for food in the late 1970s when they realized mosquito populations were increasing as frog populations declined.

Frogs, their tadpoles and eggs also serve as an important food source to a diverse array of predators, including dragonflies, fish, snakes, birds, beetles, centipedes and even monkeys. Thus, the disappearance of frog populations disturbs an intricate food web and results in negative impacts that can cascade through the ecosystem.

So it should come as no surprise that frogs have developed some interesting adaptations to cope with their lifelong need for water. For example, gastric brooding frogs, which are now extinct, swallowed their eggs. They stopped eating and digesting food while their young developed in their stomachs instead of in water. The baby frogs then exited through their parent's mouth. Strawberry poison dart frogs, which live in Central America and Puerto Rico, lay their eggs on land, and males keep them moist with urine. Once the eggs hatch, the mother carries each tadpole on her back to its own tiny pool of water that has collected between the stem and leaves of a plant. While the tadpoles grow, their mother feeds them her own eggs.

A popular distinction is often made between frogs and toads on the basis of their appearance, but this has no taxonomic basis. (Members of the anuran family Bufonidae are called true toads, but many species from other families are also called toads.) In addition to their ecological importance, frogs have many cultural roles, such as in literature, symbolism and religion, and they are also valued as food and as pets.

Muticore is an ambiguous term for software developers and one they don’t really use; software developers think in terms of threads/processes and concurrency, not how many cores or processors are available on the target. Concurrency is not a new topic either as Mark Smotherman captured in a history of multithreading, it has been a subject in computer science since its early beginnings in the 1950s.

What has changed is the rapidly increasing use of multicore technologies for embedded devices. One of the prominent software challenges that moving to multicore execution exposes is latent deadlocking bugs as true parallel execution comes into play, instead of a single core’s task scheduling/context switching techniques.

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