There are so many examples for that in different areas, like TPBi experiment carried out in our lab recently.Here's one link: http://www.alfa-chemistry.com/tpbi-cas-192198-85-9-item-282866.htm
The correct answer is option D, difficulty of redesigning workable ecosystems
Reason -
The area that was redesigned into an ecosystem actually failed to attract the endangered species of clapper rails in California because of the following two reasons –
a) Failed attempt of restoration of Cord grass ( a tree which is a dominant tree in the nesting habitat of clapper rail) . Even if few such trees were there they could not grow to their full height and thus were incapable of providing adequate nesting cover
b) Due to the lack of predatory insect, some herbivore insect in the ecosystem attacked the green grasses thereby making the nesting inadequate.
The biome that has infertile soil, principally oxisols, to which the vegetation <span>has roots systems that capture nutrients from litter decay, is the tropical rainforest.
Soil types are highly variable in the tropics and are the result of a combination of several elements or variables which includes climate, vegetation, topographic position, parent material and also the soil age. Most of the tropical soils are described by leaching and poor nutrients. It also has two classifications: namely the ultisols and oxisols. Ultisols are known as well-weathered, acidic red clays soils. They are deficient primarily in major nutrients such as potassium and calcium. Oxisols are also an acidic type of tropical soil. However, they are well drained compared to the ultisols.
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1. Well developped offspring, and portable baby food despencing. Mamalian young are generally quite well developed when they are born, and the parent does not need to find any specific types of food for the new born since the mother already provides te perfect nutrition.
2. Internal heating allows mammals to remain quick and active in cold climates.
3. Fur is really effective and cheap to produce.
