earance ▁of ▁species ▁and ▁decl ines ▁in ▁abund ance . ▁Def a un ation ▁effects ▁were ▁first ▁imp lied ▁at ▁the ▁Sym pos ium ▁of ▁Plant - An imal ▁Inter actions ▁at ▁the ▁University ▁of ▁Camp inas , ▁Brazil ▁in ▁ 1 9 8 8 ▁in ▁the ▁context ▁of ▁ne otrop ical ▁for ests . ▁Since ▁then , ▁the ▁term ▁has ▁gained ▁bro ader ▁usage ▁in ▁conservation ▁bi ology ▁as ▁a ▁global ▁phenomen on . ▁ ▁It ▁is ▁estimated ▁that ▁more ▁than ▁ 5 0 ▁percent ▁of ▁all ▁wild life ▁has ▁been ▁lost ▁in ▁the ▁last ▁ 4 0 ▁years . ▁in ▁ 2 0 2 0 ▁it ▁is ▁estimated ▁that ▁ 6 8 % ▁of ▁the ▁world ' s ▁wild life ▁will ▁be ▁lost . ▁In ▁South ▁America , ▁there ▁is ▁believed ▁to ▁be ▁a ▁ 7 0 ▁percent ▁loss . ▁ ▁In ▁November ▁ 2 0 1 7 , ▁over ▁ 1 5 , 0 0 0 ▁scient ists ▁around ▁the ▁world ▁issued ▁a ▁second ▁warning ▁to ▁human ity , ▁which , ▁among ▁other ▁things , ▁ur ged ▁for ▁the ▁development ▁and ▁implementation ▁of ▁policies ▁to ▁halt ▁" def a un ation , ▁the ▁po aching ▁crisis , ▁and ▁the ▁explo itation ▁and ▁trade ▁of ▁threatened ▁species ." ▁ ▁D ri vers ▁ ▁Over exp lo itation ▁▁ ▁The ▁int ensive ▁hunting ▁and ▁har vest ing ▁of ▁animals ▁threat ens ▁end anger ed ▁verte br ate ▁species ▁across ▁the ▁world . ▁Game ▁verte br ates ▁are ▁considered ▁valuable ▁products ▁of ▁tropical