←
Proto-Germanic *berô (cognate)←
Old High German bëro (cognate)←
Proto-Balto-Slavic *bērˀas (mention)←
Proto-Indo-European *bʰerH- (mention)←
Proto-Indo-European *bʰērH- (mention)←
Lithuanian bėras (cognate)→
Latvian brūns (mention)→
Latvian bēris (mention)→
Latvian bebrs (mention)