ical ▁requirements ▁that ▁are ▁not ▁compatible ▁with ▁those ▁of ▁the ▁m ature ▁species . ▁One ▁class ▁of ▁such ▁aggreg ations ▁compr ises ▁groups ▁of ▁adult , ▁but ▁imm ature ▁" bach elor " ▁males ▁of ▁ele ph ants , ▁se als , ▁l ions ▁and ▁other ▁animals ▁in ▁which ▁the ▁m ature ▁her d ▁will ▁not ▁toler ate ▁males ▁that ▁would ▁begin ▁to ▁comp ete ▁with ▁the ▁dominant ▁males . ▁Another ▁is ▁when ▁a pos ematic ▁lar va e ▁of ▁certain ▁insect s ▁such ▁as ▁some ▁Le pid optera ▁and ▁Hem ip tera ▁form ▁a ▁f lock ▁that ▁feed ▁together ▁and ▁may ▁migr ate ▁in ▁" process ions " ▁until ▁they ▁are ▁m ature ▁after ▁which ▁some ▁kinds ▁dis per se . ▁Most ▁species ▁of ▁migr ating ▁birds ▁and ▁m amm als ▁f lock ▁on ▁a ▁large ▁scale , ▁partly ▁for ▁protection ▁and ▁partly ▁for ▁greater ▁reli ability ▁of ▁navigation . ▁In ▁some ▁species ▁of ▁Hem ip tera ▁the ▁adult s ▁remain ▁with ▁their ▁aggreg ated ▁imm ature ▁off spring , ▁sometimes ▁in ▁protect ive ▁roles . ▁ ▁The ▁range ▁of ▁functions ▁is ▁very ▁wide ▁in ▁detail , ▁but ▁among ▁the ▁more ▁important ▁classes ▁of ▁function ▁are ▁security ▁against ▁pred ators , ▁success ▁in ▁food ▁location , ▁wide ▁range ▁of ▁mate ▁choice , ▁with ▁con com it ant ▁increase ▁of ▁out bre eding ▁opportun ities , ▁location ▁with ▁other ▁members ▁of ▁the ▁same ▁species ▁( s ometimes ▁ad her ence ▁to ▁separate ▁communities ▁can ▁almost ▁amount ▁to ▁par apat ric ▁residence ▁when ▁say