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Open access, freely available online Synopses of Research Articles Ancient DNA Tells Story of Giant Eagle Evolution DOI: 10.1371/journal.pbio.0030020 The recent discovery of a Hobbit-like hominid on the Indonesian island of Flores was startling in some respects—its rather modern existence, for one—but it represents a classic case of Darwinian evolution. For reasons that are not entirely clear, when animals make their way to isolated islands, they tend to evolve relatively quickly toward an outsized or pint-sized version of their mainland counterpart. Following this evolutionary script, the Flores woman, presumably a downsized version of Homo erectus, appears to have shared her island home with dwarf elephants and giant rats. Perhaps the most famous example of an island giant—and, sadly, of species extinction—is the dodo, once found on the Indian Ocean island of Mauritius. When the dodo’s ancestor (thought to be a migratory pigeon) settled on this island with abundant food, no competition from terrestrial mammals, and no predators, it could survive without fl ying, and thus was freed from the energetic and size DOI: 10.1371/journal.pbio.0030020.g001 constraints of fl ight. New Zealand also Giant Haast’s eagle attacking New Zealand moa (Art: John Megahan) had avian giants, now extinct, including the fl ightless moa, an ostrich-like bird, and Haast’s eagle (Harpagornis moorei), eagle in the same evolutionary lineage The absence of mammalian which had a wingspan up to 3 meters. as a group of small eagle species in competitors facilitated the evolution of Though Haast’s eagle could fl y—and the genus Hieraaetus. Surprisingly, the much larger eagles and owls on Cu