chimpanzees at ny university to be covered by habeas corpus writ .
petition by animal rights group claims chimps are ` unlawfully detained '
university rep have been ordered to attend court to respond to petition .
ruling by judge effectively recognises the chimpanzees as legal humans .
update : since the publication of this story , the court order has been amended . the order is no longer a ` writ of habeas corpus ' , which has been struck out .