“Many large species play critical roles in ecosystems Humans are pushing the extinction of marine life to an " unprecedented " level by hunting or killing larger species , according to a new study published in the journal Science . Referred to as today 's " sixth extinction , " species such as great white sharks , blue whales , and southern bluefin tuna , are being pushed to the brink by humans ' hunting habits . “ Many large species play critical roles in ecosystems and so their extinctions could lead to ecological changes that would influence the structure and function of future ecosystems beyond the simple fact of losing those species , " warns Stanford University 's professor Jonathan Payne .
Humans are pushing the extinction of marine life to an " unprecedented " level by hunting or killing larger species , according to a new study published in the journal Science . Referred to as today 's " sixth extinction , " species such as great white sharks , blue whales , and southern bluefin tuna , are being pushed to the brink by humans ' hunting habits . “ Many large species play critical roles in ecosystems and so their extinctions could lead to ecological changes that would influence the structure and function of future ecosystems beyond the simple fact of losing those species , " warns Stanford University 's professor Jonathan Payne .