▁larger ▁than ▁most ▁other ▁Je hol ▁en anti orn it he ans ▁with ▁the ▁exception ▁of ▁P eng orn is ▁and ▁X i ang orn is . ▁The ▁smallest ▁and ▁young est ▁bo hai orn ith id ▁spec im ens ▁were ▁about ▁half ▁the ▁size ▁of ▁the ▁largest ▁ones . ▁ ▁Many ▁bo hai orn ith ids ▁have ▁been ▁found ▁pres erving ▁fe athers , ▁and ▁a ▁few ▁possessed ▁a ▁pair ▁of ▁long , ▁rib bon - like ▁tail ▁fe athers ▁with ▁bar bs ▁only ▁at ▁the ▁tips . ▁These ▁special ized ▁fe athers ▁are ▁known ▁in ▁many ▁en anti orn it he an ▁spec im ens ▁( as ▁well ▁as ▁Conf u cius orn is ), ▁and ▁may ▁be ▁an ▁example ▁of ▁sexual ▁dim orphism , ▁with ▁the ▁fe athers ▁being ▁used ▁by ▁male ▁members ▁of ▁a ▁species ▁for ▁court ship ▁display . ▁A ▁sub ad ult ▁spec imen ▁of ▁an ▁ind et erm inate ▁bo hai orn ith id ▁described ▁in ▁ 2 0 1 7 ▁preserved ▁fe athers ▁on ▁various ▁parts ▁of ▁the ▁head ▁and ▁body ▁which ▁were ▁analyz ed ▁and ▁determined ▁to ▁have ▁been ▁ir ides cent ▁in ▁life . ▁ ▁Pale o ec ology ▁ ▁A ▁referred ▁adult ▁spec imen ▁of ▁Boh ai orn is ▁was ▁preserved ▁with ▁a ▁several ▁rocks ▁concentr ated ▁in ▁the ▁st om ach ▁region . ▁Ro cks ▁in ▁the ▁st om ach ▁of ▁birds ▁and ▁other ▁animals ▁are ▁often ▁believed ▁to ▁be ▁g ast rol ith s ▁sw allowed ▁to ▁assist ▁in ▁the