Why has there been a shift in the focus of the biodiversity of the entire community and the ecosystem and what would be an example of such things?
In the early years of the conservation movement (1970s), efforts were aimed mainly at the salvation of individual species—that is, saving them from extinction.
It has been recognized that saving one species will not fix the cause of the problem. That cause is usually destruction of habitat which results in a loss of biodiversity, which affects all aspects of an ecosystem. Today, it is recognized through risk assessment studies, that sometimes building a dam, or housing project may remove valuable habitat for species to find homes, for mating purposes or to find food. Deforestation has resulted in loss of habitat and because this occurs too often all around the globe, songbirds and butterfly species are in danger of extinction, for example. Tropical rainforests are cut and burned down to grow crops, or to obtain the wood to make furniture. Songbirds migrate to the tropics as do certain butterfly species. This loss of habitat is leading to species endangerment and decreased biodiversity. The animals lose places to mate and to build nests. The plants can be lost forever. This will lead to the loss of valuable medicines derived from plant and animal species that used to thrive in these habitats. Global warming will increase, due to rising carbon dioxide levels when plants are no longer available to fix the carbon during photosynthesis, into glucose. It is far more valuable to attempt to stop habitat destruction and preserve biodiversity of an ecosystem, than to save one single species. We are all dependent on one-another in the biosphere.