, ▁he ▁investig ated ▁the ▁principle ▁of ▁im print ing , ▁the ▁process ▁by ▁which ▁some ▁n id if ug ous ▁birds ▁( i . e . ▁birds ▁that ▁leave ▁their ▁nest ▁early ) ▁bond ▁instinct ively ▁with ▁the ▁first ▁moving ▁object ▁that ▁they ▁see ▁within ▁the ▁first ▁hours ▁of ▁h atch ing . ▁Although ▁Lor enz ▁did ▁not ▁discover ▁the ▁topic , ▁he ▁became ▁widely ▁known ▁for ▁his ▁descri ptions ▁of ▁im print ing ▁as ▁an ▁instinct ive ▁ ▁bond . ▁In ▁ 1 9 3 6 ▁he ▁met ▁T in ber gen , ▁and ▁the ▁two ▁collabor ated ▁in ▁developing ▁eth ology ▁as ▁a ▁separate ▁sub - dis cipl ine ▁of ▁bi ology . ▁A ▁Review ▁of ▁General ▁Psych ology ▁survey , ▁published ▁in ▁ 2 0 0 2 , ▁ranked ▁Lor enz ▁as ▁the ▁ 6 5 th ▁most ▁c ited ▁scholar ▁of ▁the ▁ 2 0 th ▁century ▁in ▁the ▁technical ▁psych ology ▁journ als , ▁intro duct ory ▁psych ology ▁text books , ▁and ▁survey ▁responses . ▁ ▁Lor enz ' s ▁work ▁was ▁interrupted ▁by ▁the ▁on set ▁of ▁World ▁War ▁II ▁and ▁in ▁ 1 9 4 1 ▁he ▁was ▁rec ru ited ▁into ▁the ▁German ▁Army ▁as ▁a ▁medic . ▁In ▁ 1 9 4 4 ▁he ▁was ▁sent ▁to ▁the ▁Eastern ▁Front ▁where ▁he ▁was ▁captured ▁by ▁the ▁Soviet ▁Red ▁Army ▁and ▁spent ▁four ▁years ▁as ▁a ▁German ▁prisoner ▁of ▁war ▁in ▁Soviet ▁Armen ia . ▁After ▁the ▁war ▁he ▁reg rett ed ▁his