3m左右雌性咸水鳄捕杀小牛鲨

鲨鱼咬伤鳄鱼的化石被发现
Paleontologists have stumbled across a scientific first that’s sure to inspire both fascination and disgust: coprolites, or fossilized fecal matter, bearing the distinct impressions of a creature’s teeth.

The coprolites — one chunk of rock is fist-sized, the other is about 30 percent larger — were discovered on a beach along the western shore of Chesapeake Bay, says Stephen Godfrey, a paleontologist at the Calvert Marine Museum in Solomons, Md.

The impressions in the coprolites are as much as 6.5 millimeters (just over a quarter of an inch) deep, Godfrey and a colleague report online March 9 in Naturwissenschaften. A silicone rubber mold of the tooth marks indicates that the biter was most likely a close relative of today’s tiger shark.

Instead, the researchers contend, the disparity in the depth of the impressions probably resulted because the fecal matter was still inside the shark’s prey, or constrained within disemboweled intestines, when bitten.

还原

据说鳄鱼有3.5米


南非海滩惊现一只鳄鱼头 疑死在鲨鱼口/组图

据英国《每日邮报》2013年1月13日报道，近日，一只鳄鱼头颅被海水冲到了南非海滩上。当地人猜测，凶手可能是只鲨鱼。

　据报道，鳄鱼头颅出现在海滩上的一幕，被南非当地人奥尼尔（Neale）和盖里-史密斯（Brigitte Cary-Smith）拍摄并上传网络后，立即引起围观。

民众纷纷猜测为何这只鳄鱼落得如此下场。

一些人认为凶手可能是捕猎者，然而另一些人认为河马和鲨鱼才是真正的罪魁祸首。

　在奥尼尔和盖里-史密斯的眼里，凶手无疑是只大白鲨。在所拍摄的视频中，奥尼尔在一旁说道：“你可以看到鲨鱼几乎是撕烂它（鳄鱼）的。”“这边的肉里，你可以看到鲨鱼牙印。”奥尼尔补充说。

到底谁才是霸主呢？