Smelling good
Fossil brain casts reveal whether allosaurus ate more like birds or alligators.
Alligator feeding strategy is based on having plenty of time. They've plenty of time to wait from something to make a mistake. It's bite first and ask questions afterwards. Birds choose to feed by picking up morsels from in between sticks, pebbles and other things - it selectively picks them up and swallows them. An alligator, on the other hand will strike at anything it sees. Tim Williams demonstrates this by leaving a cuddly toy by an alligator pool. They are opportunistic feeders. The alligators use their excellent sense of smell to track down their prey. Even a toy is tempting when dipped in fish oil. The differences between the bird and alligator behaviour is reflected in the shape of their brains. A look inside Al's head could provide direct evidence of his behaviour and a remarkable fossil has let scientists do just that. It's a brain cast from the inside of an Allosaurus skull. How does this compares with his relatives? A bird's brain has very large region dedicated to processing information, and a very small region dedicated to sensory input such as smelling. The alligator has a much larger sensory information and a smaller processing area. So it just snaps at whatever smells right. It is very similar to the allosaurus brain, so an Allosaurus behaviour should be compared to that of a modern alligator.
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