Ducks leave an impressionAlthough scientists are at odds over exactly what percentage of birds living 110 million years ago looked, walked, or quacked like ducks, they are now all in agreement about one thing - some of them had webbed feet. Recently, researchers digging near Jinju, South Korea discovered tracks of an otherwise unknown bird imprinted in clay. The scientist, who described their find in an online issue of a well-known German magazine, say the fossilized footprints override earlier evidence of when web-footed birds came into existence, pushing the date back at least 25 million years. It is assumed that birds probably made the tracks as they wadded in the shallow water in search for food. Jong-Deock Lim of the Natural History Museum at the University of Kansas also pointed out that because the space between the toes of the mystery bird were not fully webbed, they were probably only occasional swimmers, spending most of their time on land.Interestingly enough, the webbed fossil footprints, which appear alongside the fossil prints of land-dwelling birds and dinosaurs, also show evidence of a rear-pointing digit, or first toe. Scientist suspect that the earliest shore birds, having recently evolved from tree-dwelling relatives, would most likely have had such a toe.
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