Environmentalists pay attention to the high cost of protecting endangered animals and propose that we should decide which animals to be protected by evaluating the value of various endangered animals to human beings. This method is not practical, because it is impossible to predict the future value of an animal. It is also impossible to evaluate the value of animals that make indirect but important contributions to human beings today.
the main argument of above?
Protecting worthless endangered animals is more important than protecting potentially valuable animals.