Chiappe et al. ( 1998 ) described another Mongolian member , Shuvuuia deserti .
Chiappe et al. ( 1998 ) mistakenly found it to be even more derived , concluding that the alvarezsaurs were actually crown - group ( that is , modern ) birds .
Chiappe et al. ( 1998 ) described another Mongolian member , Shuvuuia deserti and mistakenly found it to be even more derived , concluding that the alvarezsaurs were actually crown - group ( that is , modern ) birds .