马和驴是两个物种是因为（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29829' and id < 2420957 and id<>'2420957' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29829' and id > 2420957 and id<>'2420957' order by id asc limit 5