The apex predator here was Majungasaurus crenatissimus, a stocky, short-snouted abelisaurid roughly seven meters long with a single thickened horn on its skull. French paleontologist Charles Depéret first named it in 1896 - from a handful of teeth he mistook for a species of Megalosaurus - and it took until 1955 for René Lavocat to recognize it as something new and rename it for the Mahajanga region. But the strangest discovery came later. Majungasaurus bones bear tooth marks spaced and shaped to match Majungasaurus teeth. It remains the clearest evidence of cannibalism in any non-avian dinosaur on record. Whether they hunted their own kind or simply scavenged the drought's dead, no one can say. In a landscape that starved on a schedule, a meal was a meal.

Then there is the frog. In 2008, scientists described Beelzebufo ampinga from fragments of an enormous skull and armored back - a name stitched together from Beelzebub and the Latin for toad. Early estimates suggested it may have grown up to 41 centimeters long and weighed around four and a half kilograms - though later studies revised that figure downward, the animal was still larger than any frog alive today. Its species name, ampinga, means shield in Malagasy, for the bony plates fused across its back. With jaws that broad and a bite that powerful, Beelzebufo was no insect-eater. Researchers think it ambushed prey the way modern horned frogs do, swallowing whatever it could overpower - lizards, snakes, perhaps even hatchling dinosaurs unlucky enough to hop within reach.

By the late Cretaceous, Madagascar had drifted free of Africa and India and floated alone in the widening Indian Ocean. Its isolation shows in the fossils. Alongside Majungasaurus lived Masiakasaurus, a small predator whose front teeth jutted forward like a pitchfork, and the long-necked sauropods Rapetosaurus and Vahiny. Crocodile relatives were everywhere - at least seven kinds, sharing the rivers with turtles, gars, and lungfish. There were birds too, including Rahonavis, a crow-sized flier with a killing claw on each foot. Many of these creatures show closer kinship to animals of South America than to nearby Africa, a clue to how the southern continents were once stitched together in the supercontinent Gondwana.

Almost everything known about this lost world comes from the Mahajanga Basin Project, a joint effort of Stony Brook University and the University of Antananarivo that has mounted expedition after expedition since 1993. The first season alone turned up hundreds of theropod teeth; the seasons since have produced tens of thousands of fossils, many belonging to species new to science. It was this project, led by paleontologist David Krause, that recovered the near-complete Majungasaurus skull that finally settled the animal's identity. The work continues because the Maevarano keeps giving. Each dry season, erosion lifts a little more sandstone away, and another fragment of Madagascar's deep past surfaces in the light.