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Ostriches have bloodless erections , according to researchers .

研究发现鸵鸟在勃起时不充血。

Gone are the zebras , kangaroos and ostriches .

斑马，袋鼠和鸵鸟也不见了踪影。

Yasnogorodka , ukraine : ostriches on a farm

乌克兰雅斯诺格罗德卡：农场里的鸵鸟。

Ostriches offer clues to dinosaur motion

鸵鸟为研究恐龙运动方式提供线索

And a local farm has recently had to put down one of its ostriches .

近来一家当地农场不得不了结一只鸵鸟。