Part Ⅰ Reading Comprehension

Agatti is one of the Lakshadweep Islands of the south-west coast of India. These islands are surrounded by lagoons and coral reefs which are in turn surrounded by the open ocean. Coral reefs, which are formed from the skeletons of minute sea creatures, give shelter to a variety of plants and animals, and therefore, have the potential to provide a stream of diverse benefits to the inhabitants of Agatti Island.

    In the first place, the reefs provide food and other products for consumption by the islanders themselves. Foods include different types of fish, octopus and molluscs, and in the case of poorer families, these constitute as much as 90% of the protein they consume. ……此处隐藏24720个字…… on.

    When Darwin think why each bird was bestowed with these particular features, he began to formulate his theory of natural selection. Darwin saw potential for adaptation. The advantageous variation would be passed on. The evolutionary process, called survival of the fittest, forms a new species.

    Darwin noted that the finches of the Galapagos and South America have resemblances. The disoriented ancestors found a home on volcanic islands of the Galapagos. The individuals among subsequent generations that were fitter or better adapted to certain conditions of the population's new home, continued the breeding process, and thus, new species evolved.