THE FIRST 85-MILLION YEARS OF AVIAN EVOLUTION

More than half of the evolutionary history of birds is played out in t he Mesozoic. A recent burst of fossil discoveries has documented a tre mendous diversity of early avians. Clarification of the Phylogenetic s tructure of this diversity has provided clues for a better understandi ng of the evolution of functional, developmental and physiological cha racteristics of modern birds. Yet their long Mesozoic history is only beginning to be deciphered.