Why are amphibians considered as unsuccessful land vertebrates?

Select all the adaptations in amphibians that allowed them to become successful on land.Multiple select question.more complex circulatory systemeyelids and acute hearingamniotic eggimproved lungsdenser skeletonscaly, thick skin

Over the past thirty years, the global population of amphibians has decreased dramatically. Although most of these changes in population have occurred in North and South America, amphibian extinction is a worldwide phenomenon. Some scientists estimate that over 120 species of amphibians have become extinct since 1980. This threat to the amphibian population is also a threat to biodiversity, meaning the variety of species that lives within a natural habitat.Many experts believe that amphibians are at heightened risk because they are especially sensitive to changes human beings have made to the environment. Because amphibians live in water when they are young and on land as adults, they are affected by both aquatic and terrestrial pollution. For example, studies have shown that pesticides and herbicides used by farmers can contaminate both water and land habitats, killing off tadpoles and adult frogs alike.Another major risk to amphibians is habitat destruction. Amphibians are more vulnerable to habitat destruction than other species because they require two different types of habitats. Habitat destruction occurs in many ways. Sometimes human beings physically alter amphibian habitats, such as clearing land, to make them more suitable for farming or fishing. Other forms of habitat destruction are less obvious. For example, some biologists believe that fertilizer run-off from farms has caused an increase in the population of trematodes, parasites that cause fatal deformities in tadpoles.In addition to harmful chemicals, intrusive species can also negatively impact amphibian populations. In the lakes of the Sierra Nevada region, for instance, recreational fishers have introduced non-native trout that threaten the yellow-legged frog population. The trout eat both the tadpoles and the young frogs, thus causing a steep decline in the number of mature frogs.While destruction of habitat, chemical contamination, and introduction of non-native species are the most overt causes of amphibian population decline, some scientists have suggested that noise pollution, though less obvious, is also a major factor. Reproduction amongst frogs and toads depends largely upon vocalizations, or mating calls. Noise from traffic, factories, and airports can drown out these vocalizations, dramatically altering the amphibian mating process and leading to fewer offspring.Although a sharp decline in the amphibian population is a great threat to biodiversity, many scientists contend that it also serves as an indicator for larger environmental issues, such as global warming or increased levels of toxic pollutants. These scientists argue that because amphibians are exceptionally vulnerable to environmental threats, declines in their population suggest that other species living in these habitats will soon experience similar detrimental effects.The widespread endangerment of amphibian populations has caused scientists and environmentalists alike to call for stricter conservation practices. In 2007, an international group of biologists founded the Amphibian Ark, a group dedicated to preserving amphibians through captive breeding programs. Many other organizations have funded studies to investigate the causes of amphibian deaths as well as programs to conserve habitats and educate local citizens about ways to help protect the amphibian population."Amphibians." Under and Above, Web, 24 Mar. 2012.SubmitThe primary purpose of the passage is toAdiscuss the role habitat plays in the amphibian life cycleBpersuade readers to join conservation groups to stop amphibian population declineCinform readers about the possible causes of amphibian population declineDcriticize humans for their careless destruction of amphibian habitatsEwarn scientists that amphibian population decline can signal larger problems in the environment

Write down the basic      difference between      amphibians and      reptiles

Amongst the animal groups given below, which one appears to be more vulnerable to extinction?AInsectsBMammalsCAmphibiansDReptiles

Frogs are classified as amphibians.State two features of amphibians that distinguish them from all other vertebrates