NATURAL SELECTION.

This article focuses on the survival strategies of airport hubs. The art of the airport hub is changing. Everything is spreading worldwide, deregulated markets, discount airlines, the mortality of network carriers and the growing importance of airline alliances. Chicago, Dallas-Fort Worth and Atlanta in the U.S.. and Tokyo, Singapore and Hong Kong in Asia. Airport consolidation is only increasing the importance of "fortress hubs" for the major carriers, Delta Air Lines Inc. in Atlanta Hartsfield, having pulled back from Dallas-Fort Worth, and British Airways PLC in London Heathrow, having pulled back from London Gatwick, are examples. It recently emerged from bankruptcy protection as a reinvented low-cost carrier with a concentration on two hubs, its main base at Toronto Pearson International Airport and Vancouver International Airport for Asian connections.